Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://www.stsci.edu/~marel/pdfdir/STScINewsl21_3_04.pdf Äàòà èçìåíåíèÿ: Sun Jul 18 23:45:30 2004 Äàòà èíäåêñèðîâàíèÿ: Sat Dec 22 03:52:14 2007 Êîäèðîâêà: Ïîèñêîâûå ñëîâà: heart nebula

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Spa ce T elescope Science Institute

Title of Cover Article The Cycle 13 Proposal Peer Review
Author Name, email@stsci.edu D. Macchetto, macchetto@stsci.edu, R. Williams, wms@stsci.edu, B. Blacker, blacker@stsci.edu Overview

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SUMMER



2004

U

nder an accelerated schedule, which has significantly shortened the time between proposal submission and observations, the Time Allocation Committee (TAC) and 11 discipline panels met in Baltimore at the end of March to evaluate the 949 proposals that were submitted in late January for Cycle 13 of Hubble observations and archival research. As Cycle 12 observations draw to a close this summer and Cycle 13 observations begin in July, publication and citation metrics point to the ever-increasing scientific productivity of Hubble. This in part reflects the high productivity of its mature instruments: the Advanced Camera for Surveys (ACS), Space Telescope Imaging Spectrograph (STIS), and Near Infrared Camera and Multi- Object Spectrometer (NICMOS). Hubble's scientific success also reflects the intense competition for observing time--the Cycle 13 oversubscription in requested orbits was 5.5 to 1--and the care and consideration of the TAC and its panels in recommending the best proposals for selection. When the Cycle 13 Call for Proposals (CP) was initially released in late summer of 2003, it was thought that the next Hubble servicing mission would install the Cosmic Origins Spectrograph (COS) and Wide Field

Camera 3 (WFC3) near the end of the cycle. NASA Administrator O 'Keefe's decision in January 2004 to cancel all further Shuttle servicing missions to the Hubble precluded not only the installation of COS and WFC3, but any likely visits to Hubble for replacement of existing components for at least 3­4 years. All observations for Cycles 13­15 will almost certainly be performed using the existing Hubble instruments. One novel feature of the Cycle 13 TAC process was transparent to the community: it was essentially paperless. Every step--from issuance of the CP to submission/receipt of proposals, to their dissemination and evaluation by the panelists, to the notification of Principal Investigators (PIs)--was performed electronically. The Institute did offer to provide the necessary resources to any Cycle 13 panelist who wished to have paper copies of proposals to review, but only one out of one hundred panelists insisted on it. An electronic process requires much less time from start to finish. Cycle 13 also utilized a more robust Astronomer 's Proposal Tools software package, with which many PIs had gained some familiarity. The process of proposal writing and submission went smoothly for the vast majority of PIs and Co -Is. Continued



Image Credit: The Hubble Heritage Team of astronomers celebrated its five-year anniversary with the release of the picturesque Sombrero galaxy, one of the largest Hubble mosaics ever assembled.


DIRECTOR'S PERSPECTIVE

Living among the Stars
Steven Beckwith, svwb@stsci.edu

was flying from Berlin to Washington, changing planes in Munich. Before boarding in Munich, there was a second layer of security, the gate agents ever vigilant for terrorists flying to America. "Step over to the lady on your right," said the ticket agent, "She will ask you a few questions."
I stepped to the right and prepared to state that I had packed my own bags, they never left my side, I never take gifts from strangers, and I was not carrying large sums of money, agriculture products, or small animals. It needed to be quick. I did not yet have a boarding pass, and the passengers were beginning to board. The woman took my passport, noted the number of stamps, countries, and visas and asked in heavily accented English, "Are you a scientist?" Good guess on the first try. Scientists travel a lot, a fact she knew, but something else must have given me away. Time for a shave. " Yes," I answered. Keep it short, I thought. " What kind?" "I am an astronomer." My answer elicited a broad smile from my interrogator. "Oh, how nice," she said. " Tell me, can you see back in time?" My colleagues and I had just released the Ultra Deep Field two months earlier, so I was well prepared for this question. I explained how light took time to travel over large distances, and we can look far back in time by observing the light from objects far away, a kind of cosmic time machine--the sound bite popping out before I could squelch it. "How far back can you see?" she pressed. "About 13 billion light years," and I said it again in German to avoid confusion with the American use of billion. She was immediately taken with this line of thought and spent the next few minutes asking me questions about the early universe, did I believe in black holes, did I think there was life out there, and if we Americans would save the Hubble Space Telescope. Usually at ease with this kind of conversation, I was nervously watching the other passengers board, convinced that these questions were not in the manual provided by United Airlines. Nevertheless, I was not going to argue with security. Finally, she capped the conversation by saying, " You astronomers are so lucky. You live among the stars, not among the people." I gratefully accepted this graceful metaphor for our scientific passion, thanked her, and she let me go, having neglected to ask if I had packed my own bags (I had). In a taxi in Berlin that morning, my driver had struck up a conversation with me in broken German--he was obviously a recent immigrant as I had also been in the same country 13 years ago. It did not take him long to discover I was an astronomer. " What is happening to the Hubble Space Telescope?" he asked. "Is it going to die?" "Not yet," I replied. "But it will not last more than a few more years without a visit." " Why are the Americans so afraid," he asked again, "that they don't want to fly to Hubble?" This question has become a common theme abroad, the incredulity at the Hubble decision unfortunately enhanced by the unrelated, but prominent, events in Iraq. All over the world, people know Hubble and ask me about it as soon as they learn my profession, usually before they have any hint of my deep connection to the telescope. Hubble has penetrated the public consciousness to an unprecedented degree for an astronomy project. There have been other times in history when a scientific idea, experiment, or practitioner became part of popular culture--the Theory of Relativity, the explosion of the first atomic bomb, and Carl Sagan, come to mind--but this happens infrequently. We are fortunate that one of our own astronomical projects, the Hubble Space Telescope, has become a modern icon of the progress of civilization. Even correcting for my obvious bias as an ardent Hubble hugger, there is little doubt that my experience mirrors those of most of my readers. Hubble connects us with the world at large. NASA is now looking hard for means of keeping Hubble alive without risking the lives of astronauts. The only realistic way to extend Hubble's life much beyond 2007 is to visit it again, changing batteries and gyroscopes and, hopefully, installing the two new focal plane instruments. NASA has to visit Hubble again just to strap on a de - orbit module. Doing a bit more is a logical way to accomplish two goals with one mission. Without astronauts, we will have to send robots. The team at Goddard Space Flight Center, with support from the Institute, is working out ways to do just that: send robots to add new battery packs, gyroscopes, and, yes, install the new instruments, too. My colleagues ask often if such a mission is plausible. I have seen

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DIRECTOR'S PERSPECTIVE
the laboratory demonstrations of one such system and asked a group of Institute experts to review the technical feasibility. One of our experts, David Hunter, held a series of high-level positions in the Canadian Space Agency building robots for the International Space Station, including the Special Purpose Dexterous Manipulator arm (SPDM). David's assessment is that a servicing mission using SPDM is a challenge but that all the tasks are doable. That 's my assessment, too. It is good news for all of us that NASA is looking favorably on a comprehensive robotic servicing mission, especially with installation of two new scientific instruments, which would keep Hubble scientifically productive for another eight years or so. It will be challenging, it will be expensive, and it will not be as tried and true as the servicing missions with astronauts, but it may achieve all of our scientific goals, and it certainly will not risk any lives in the process. This special challenge is just the kind of work that has brought NASA kudos in the past as a can-do agency. I am optimistic that we can service Hubble by some method one more time in late 2007, extending its life another five or six years. The Hubble team has faced similar challenges in the past. Each time, the team has achieved every goal. Right now, we are living very much among people doing the hard work of putting together an entirely new kind of servicing mission so that our users can continue living among the stars.

Cycle 13 Review from page 1

Peer Review Process As reported in the Fall 2002 Newsletter, an external review of the Institute's TAC process in summer 2002 affirmed the basic integrity and effectiveness of the Hubble peer review.1 Nevertheless, it recommended certain changes, which were implemented in the Cycle 12 TAC process. Among these recommendations were relaxing conflict- of-interest rules governing panelists' evaluation of proposals submitted from their own institutions and providing reviewer comments to PIs communicating the panel assessment. The procedure by which the peer review panels identify the best Hubble proposals has evolved since its inception, although it has experienced relatively minor changes in recent cycles. It has distinctive features that are driven by the needs to evaluate a large number of proposals in each cycle and to make cross - disciplinary comparisons between proposals. These features include the following. Two -Tiered TAC & Panel Evaluation. Proposals are divided into two categories depending upon the level of observing time and resources requested: Large (>100 orbits), Treasury, and Archival Legacy. General Observer proposals are first reviewed by the appropriate discipline panel, then evaluated and ranked by the interdisciplinary TAC, which consists of the chairs of the 11 discipline panels plus the TAC Chair. The Director normally assigns ~1/3 of the available observing time to these larger programs. The remaining ~2/3 of observing time is devoted to smaller programs, which are evaluated exclusively by the individual discipline panels and recommended for observing time and funding. Proposal Triage. Each proposal is read by all panelists, and reviewed by one primary and two secondary reviewers with research expertise in that field. We make reviewer assignments by maximizing keyword matches specifying proposal subject and panelists' research areas. Grades are tallied before the meeting, and the lowest-ranked 1/3 of the proposals are triaged out of the process. Nevertheless, the request of a single panelist can fully reinstate any triaged proposal back into the evaluation process. Mirror Panels. Except for the solar system panel, each discipline is covered by at least two "twin" panels, which enables proposal assignments on the basis of maximizing expertise and minimizing conflicts of interest. This feature has also led to an acceptance rate for proposals on which panelists are PIs that is the same as that for non-panelist PIs. Progressive Orbit Subsidy. In order to encourage panels to resist the tendency to favor smaller programs because of the greater number that can be approved for the limited orbits available to a panel, the Institute subsidizes the cost in orbits charged to the panel for Continued all proposals approved for more than 15 orbits. For each orbit approved for page 4 scheduling above that number, an increasing fraction of the orbits is
1

http://www.stsci.edu/resources/tac_assessment



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Cycle 13 from page 3

charged against a pool of orbits held in reserve. The resulting incentive for moderate - sized programs (between 15­100 orbits) has succeeded in producing a more uniform distribution of program sizes. Proposal Feedback We provide comments that the PI. The primary reviewers of the panel discussion. The scientist), and the panel chair Coordinated Observations Cycle 13 continued the collaboration between the Institute, the National Optical Astronomy Observatories, and the Chandra X-ray Center to provide for observing time on the Hubble and either Chandra or NOAO telescopes. Under this program, proposers for Hubble observing time may also receive observing time on the other facilities as necessary for the science objectives of the Hubble proposal, up to a maximum of 400 ksec on Chandra and 20 nights on NOAO telescopes. Future Cycles The Institute considers the proposal review process to be one of its most important activities, and we remain open to suggestions for improvements to the current process. Although we do not anticipate major changes to our procedures, we are aware that Hubble's capabilities may change if it is not serviced in the near future. In particular, we are concerned that gyro failures or power limitations may diminish performance. We are working with the community to address how best to maximize the science under the various operational scenarios. These considerations could conceivably impact the manner of proposal evaluation in upcoming cycles. As we approach the first observations of Cycle 13, we are appreciative of the excellent work of the Cycle 13 TAC, the panels, and especially TAC Chair Wendy Freedman. Their efforts should result in another year of outstanding science from Hubble. reflect the panel discussion and assessment of each proposal to are responsible for combining the three reviews with a synopsis secondary reviewers, the panel support scientist (an Institute review the comments before they are sent to the PIs.

Hubble Refines Distance to Pleiades Star Cluster
stronomers using NASA's Hubble Space Telescope have helped settle a mystery that has puzzled scientists concerning the exact distance to the famous nearby star cluster known as the Pleiades, or the Seven Sisters. The mystery began in 1997, when the European Space Agency's satellite Hipparcos measured the distance to the Pleiades and found it is 10 percent closer to Earth than traditional estimates, which were based on comparing the Pleiades to nearby stars. If the Hipparcos measurements were correct, then the stars in the Pleiades are peculiar because they are fainter than Sun-like stars would be at that distance. This finding, if substantiated, would challenge our basic understanding of the structure of stars. But measurements made by the Hubble Space Telescope's Fine Guidance Sensors show that the distance to the Pleiades is about 440 light-years from Earth, essentially the same as past distance estimates and differing from the Hipparcos results by more than 40 light-years. Image Credit: NASA , ESA and AURA/Caltech

A



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Cycle 13: TAC and Panel Members
Member
TAC Chair Wendy Freedman Car negie Institution of Washington

Institution

Member

Institution

Extragalactic Panel Members Itziar Aretxaga Lee Ar mus Jack Baldwin Andrew Blain John Blakeslee Allesandro Capetti Chris Carilli Stephane Charlot Jane Charlton Chris Conselice Frederic Courbin Sandra Faber Andrew Fabian (Chair) Jack Gallimore Karl Gebhardt Rosa Gonzalez Delgado Richard Green (Chair) Christine Jones (Chair) Guinevere Kauffmann Charles Keeton Jean-Paul Kneib Steve Kraemer Francesca Matteucci Patrick McCar thy (Chair) Brian McNamara Aver y Meiksin Leo Metcalfe Heather Mor rison Julio Navar ro Michael Pahre Rosalba Per na Patrick Petitjean Jason Prochaska Alice Quillen Brigitte Rocca-Volmerange Lar r y Rudnick John Salzer Rita Sambr una David Sanders Craig Sarazin Joe Shields Daniel Ster n Pieter van der Kr uit (Chair) Joachim Wambsganss Liliya W illiams Instituto Nacional de Astrofisica, Optica y Electronica Califor nia Institute of Technology Michigan State University Califor nia Institute of Technology The Johns Hopkins University Osser vatorio Astronomico di Torino National Radio Astronomy Obser vator y Max-Planck-Institut fÝr Astrophysik/CNRS, Institute d'Astrophysique de Paris The Pennsylvania State University Califor nia Institute of Technology UniversitÈ de Liege University of Califor nia - Santa Cr uz University of Cambridge Bucknell University/Space Telescope Science Institute University of Texas at Austin Instituto de Astrofisica de Andalucia (IAA) National Optical Astronomy Obser vatories Smithsonian Institution Astrophysical Obser vator y Max-Planck-Institut fÝr Astrophysik University of Chicago Obser vatoire Midi-PyrÈnÈes/Califor nia Institute of Technology Catholic University of America/NASA Goddard Space Flight Center INAF - Osser vatorio Astronomico di Trieste Car negie Institution of Washington Ohio University University of Edinburgh, Institute for Astronomy XMM-Newton Science Operations Centre Case Wester n Reser ve University University of V ictoria Smithsonian Institution Astrophysical Obser vator y Princeton University CNRS - Institute d'Astrophysique de Paris University of Califor nia - Santa Cr uz University of Rochester CNRS - Institute d'Astrophysique de Paris University of Minnesota - Twin Cities Wesleyan University George Mason University University of Hawaii The University of V irginia Ohio University Jet Propulsion Laborator y Kapteyn Astronomical Institute Astrophysikalisches Institut Potsdam University of Minnesota

Solar System Panel Members Michael A'Hear n Fran Bagenal Nicolas Biver Michael Brown (Chair) John Clarke Richard French Bill Merline Anne Verbiscer Diane Wooden Galactic Panel Members Tom Ayres Mar tin Barstow (Chair) Gisella Clementini Stephanie Cote Pier re Cox Giuseppe Cutispoto Francesca D'Antona Helene Dickel Andrea Dupree (Chair) Suzan Edwards Cesara Esteban Rob Fesen (Chair) Pete Gar navich Doug Gies Alice Harding Falk Her wig David Hollenbach Steve Howell Chris Howk Ed Jenkins James Lieber t David Meyer Tony Moffat Siobahn Morgan Jon Morse Bob O'Dell George Pavlov Daniel Pequignot Elana Pian Edward Robinson Roger Romani Rober t Rood Abhijit Saha (Chair) Bradley Schaefer H.M. Schmid Regina Schulte-Ladbeck (Chair) Allen Shafter John Thorstensen Alan Tokunaga Kim Venn Br uce W ilking Lee Anne W illson Frank W inkler Guy Wor they Rober t Zinn University of Colorado at Boulder University of Leicester Osser vatorio Astronomico di Bologna Dominion Astrophysical Obser vator y Institut d'Astrophysique Spatiale INAF - Catania Astrophysical Obser vator y INAF - Osser vatorio Astronomico di Roma University of Illinois at Urbana - Champaign Smithsonian Institution Astrophysical Obser vator y Smith College/University of Massachusetts Instituto de Astrofisica de Canarias/Universidad de La Laguna Dar tmouth College University of Notre Dame Georgia State University Research Foundation NASA Goddard Space Flight Center Los Alamos National Laborator y NASA Ames Research Center National Optical Astronomy Obser vatories University of Califor nia - San Diego Princeton University University of Arizona Nor thwester n University UniversitÈ de Montreal University of Nor ther n Iowa Arizona State University Vanderbilt University The Pennsylvania State University Obser vatoire de Paris - Section de Meudon INAF - Osser vatorio Astronomico di Trieste University of Texas at Austin Stanford University The University of V irginia National Optical Astronomy Obser vatories Louisiana State University & Agricultural & Mechanical College Eidgenossiche Technische Hochschule (ETH) University of Pittsburgh San Diego State University Dar tmouth College University of Hawaii Macalester College/University of Minnesota Twin Cities University of Missouri - Saint Louis Iowa State University Middlebur y College Washington State University Yale University University of Mar yland University of Colorado at Boulder Obser vatoire de Paris - Section de Meudon Califor nia Institute of Technology Boston University Wellesley College Southwest Research Institute The University of V irginia NASA Ames Research Center



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Proposals By Country
Country
Australia Austria Belgium Brazil Canada Chile France Germany Greece India Ireland Israel Italy Japan Korea Mexico Poland Russia South Africa Spain Sweden Switzerland The Netherlands United Kingdom Venezuela United States ESA Countries

Submitted
13 1 3 2 6 3 13 29 2 1 3 3 22 1 1 3 1 3 1 8 5 6 11 55 1 752 169

Approved
2 0 2 1 2 0 2 5 0 0 0 1 2 0 0 0 0 1 0 2 0 1 4 9 0 175 31

Summary of Cycle 13 Results
Proposals
General Observer Snapshot Archival Research AR Legacy Theory Total Primary Orbits

Requested Approved % Accepted ESA Accepted ESA % Total
739 82 89 6 33 949 17257 144 21 31 1 12 209 3111 19.5% 25.6% 34.8% 16.7% 36.4% 22.0% 18.0% 28 3 19.4% 14.3%

31 489

18.8% 15.7%

Orbit Results By Science
Solar Systems 2%

Proposal Results By Science
Solar Systems 9%

AGN 6% Stellar Pops 11% Cosmology 14% Star Formation 10%

AGN 10% ISM 10% Cosmology 9% Stellar Pops 14% Hot Stars 11% Star Formation 4% Galaxies 19% ISM 12% Cool Stars 2% QAL 9% Galaxies 25%

Hot Stars 12%

QAL 5%

Cool Stars 6%



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US Proposals By State
State Submitted
8 56 114 36 6 27 5 12 8 12 15 5 4 5 47 147 19 8 5 1 3 12 11 36 16 1 1 49 1 4 5 34 12 13 10 4

Approved
0 11 33 9 4 4 0 0 1 2 6 0 3 1 10 36 4 1 0 0 1 4 2 5 4 1 0 12 0 1 0 11 2 5 1 1

Instrument Statistics
Instruments
ACS/HRC ACS/HRC ACS/SBC ACS/SBC ACS/WFC ACS/WFC FGS FGS NIC1 NIC2 NIC3 NIC3 STIS/CCD STIS/CCD STIS/FUV STIS/FUV STIS/NUV STIS/NUV WFPC2 Total

Mode
Imaging Spectroscopy Imaging Spectroscopy Imaging Spectroscopy POS TRANS Imaging Imaging Imaging Spectroscopy Imaging Spectroscopy Imaging Spectroscopy Imaging Spectroscopy Imaging

Requested Orbits
1714 11 141 12 8114 96 366 29 363 1412 1652 74 375 835 54 2790 22 1625 2119 21804

%
7.9% 0.1% 0.6% 0.1% 37.2% 0.4% 1.7% 0.1% 1.7% 6.5% 7.6% 0.3% 1.7% 3.8% 0.2% 12.8% 0.1% 7.5% 9.7%

Approved Orbits
267 0 6 7 1413 0 0 29 37 373 346 0 29 273 18 532 7 355 344 4036

%

41.9%

0.7% 18.7%

30.1% 8.5%

Orbits include coordinated parallel usage Excludes Pure Parallel and Snapshot programs

AL AZ CA CO CT DC DE FL GA HI IL IN KY LA MA MD MI MN MO NC NH NJ NM NY OH OK OR PA RI SC TN TX VA WA WI WY

Proposal Acceptance Ratio
Oversubscription by Cycle
9 8 GO Proposal oversubscription GO Orbit oversubscription AR Funding oversubscription

Oversubscription Ratio

7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 7N Cycle 8 9 10 11 12 13



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Name

Institution

Type

Title

Extragalactic Programs



8
GO GO GO GO SNAP GO AR AR GO SNAP GO GO AR GO GO AR SNAP GO AR GO GO GO SNAP GO GO GO GO GO GO GO AR GO GO GO AR AR Stars versus Gas: A Direct Comparison of Black Hole Mass Measurement Techniques ACS/NICMOS Imaging of Bright Lyman Break Galaxy Candidates from SDSS The Masses of the Ultraluminous X-ray Sources Ultracompact Blue Dwarfs: Galaxy Formation in the Local Universe? Cluster Archeology: The Origin of Ultra-Compact Dwarf Galaxies Low-Ionization BALs: Evolution or Orientation? Numerical Simulations of Outflows in Quasars: The Microphysics of BAL Winds Searching for Quasar-intrinsic Absorption through Time Variability Dark vs. Luminous Matter in the CenA/M83 Galaxy Complex Dark-matter Halos and Evolution of High-z Early-type Galaxies Tracing the Emergence of the Hubble Sequence among the Most Luminous and Massive Galaxies Structure of the Accretion Disk in the NLS1 NGC 4051 Outflows from Seyfert Galaxies: A Challenge to Current Models The Nuclear Scattering Geometry of Seyfert Galaxies A Fundamental Test of Accretion Physics with NGC 4203 Formation of Structure in AGN Accretion Disk Winds: Theory and Observational Implications Infrared Snapshots of 3CR Radio Galaxies What Drives the Outflows in Powerful Radio Galaxies? The Distribution of Stars around the Massive Black Hole at the Galactic Center A Coordinated NICMOS and XMM Experiment to Observe the Variability of Sgr A* Abundances in AGN Outflows: Putting Real Numbers into Quasar Feedback Scenarios A Multiwavelength Study of POX 52, a Dwarf Seyfert Galaxy with an Intermediate-mass Black Hole The Most Massive Galaxies in the Universe: Double Trouble? HST/Chandra Monitoring of a Dramatic Flare in the M87 Jet The Origin of Dwarf Galaxies and Steep Luminosity Functions in Clusters Solving the Mystery of the Short-hard gamma-ray Bursts Radial Velocity Variability in the Mass Outflow in the Seyfert 1 Galaxy NGC 3783 Globular Cluster Systems of Giant, Post-starburst Shell Ellipticals The ACS Fornax Cluster Survey The Coevolution of Supermassive Black Holes and Galaxies at z ~ 3 Morphological Analysis of z = 5.7 Lyman alpha Sources in the GOODS/UDF Fields Resolving Globular Clusters in NGC 1399 Probing the Surroundings of a Highly Luminous Redshift 6.5 Galaxy The Size and Shape of a Spiral Galaxy's Gaseous Halo The Globular Cluster Systems of Low-mass Spiral Galaxies The Physical Nature of Galaxy Morphology during the Peak Epoch of Galaxy Formation



CYCLE 13: Approved Observing Program s

Aaron Barth Misty Bentz Joel Bregman Michael Corbin Michael Drinkwater Xiaohui Fan Gary Ferland Rajib Ganguly Igor Karachentsev Leon Koopmans Claudia Kretchmer Bradley Peterson Daniel Proga Andrew Robinson Joseph Shields Isaac Shlosman William Sparks Clive Tadhunter Farhad Yusef-Zadeh Farhad Yusef-Zadeh Nahum Arav Aaron Barth Mariangela Bernardi John Biretta Christopher Conselice Derek Fox Jack Gabel Paul Goudfrooij Andres Jordan Chien Peng Norbert Pirzkal Thomas Puzia James Rhoads Jessica Rosenberg Anil Seth Charles Steidel

California Institute of Technology Ohio State University University of Michigan Space Telescope Science Institute University of Queensland University of Arizona University of Kentucky Space Telescope Science Institute Russian Academy of Sciences, Special Astrophysical Obs. Kapteyn Astronomical Institute The Johns Hopkins University Ohio State University University of Colorado at Boulder Rochester Institute of Technology Ohio University University of Kentucky Space Telescope Science Institute University of Sheffield Northwestern University Northwestern University University of Colorado at Boulder California Institute of Technology Carnegie Mellon University Space Telescope Science Institute California Institute of Technology California Institute of Technology University of Colorado at Boulder Space Telescope Science Institute Rutgers, the State University of New Jersey University of Arizona Space Telescope Science Institute Space Telescope Science Institute Space Telescope Science Institute University of Colorado at Boulder University of Washington California Institute of Technology


Name

Institution

Type

Title

CYCLE 13: Approved Observing Program s



9



Nicole Vogt Rachel Webster Lin Yan Almudena Alonso-Herrero C. Carollo Seth Cohen Frederic Courbin Arlin Crotts Donald Garnett Armando Gil de Paz Karen Leighly Jodie Martin Hagai Netzer Christopher O'Dea Jason Prochaska Douglas Richstone Rachel Somerville Thaisa Storchi-Bergmann Bradley Whitmore Wei Zheng Narciso Benitez Megan Donahue Richard Ellis Christopher Fassnacht David Kirkman George Miley Priyamvada Natarajan Jason Rhodes Regina Schulte-Ladbeck David Turnshek David Tytler Scott Anderson Romeel Dave Richard Ellis Christopher Fassnacht Marijn Franx Nickolay Gnedin Caryl Gronwall

New Mexico State University University of Melbourne Jet Propulsion Laboratory Instituto de Estructura de la Materia Eidgenossiche Technische Hochschule (ETH) Arizona State University UniversitÈ de Liege Columbia University in the City of New York University of Arizona Carnegie Institution of Washington University of Oklahoma Norman Campus The University of Virginia Tel Aviv University - Wise Observatory Space Telescope Science Institute University of California - Santa Cruz University of Michigan Space Telescope Science Institute Universidade Federal do Rio Grande do Sul Space Telescope Science Institute The Johns Hopkins University Instituto de Astrofisica de Andalucia (IAA) Michigan State University California Institute of Technology University of California - Davis University of California - San Diego Universiteit Leiden Yale University California Institute of Technology University of Pittsburgh University of Pittsburgh University of California - San Diego University of Washington University of Arizona California Institute of Technology University of California - Davis Universiteit Leiden University of Colorado at Boulder The Pennsylvania State University

GO GO AR GO GO AR GO GO GO AR GO AR GO SNAP GO GO AR GO GO AR GO SNAP AR GO AR GO AR AR AR GO GO SNAP AR GO AR GO AR AR

Mass Distributions of z ~ 1 Galaxies: Probing Substructure and Dynamical Evidence for Bulges in Velocity Profiles Microarcsecond Imaging of a Gravitationally Lensed QSO: 2237+0305 Extremely Red Galaxies at z > 1 in the COSMOS Field Star Formation in Luminous Infrared Galaxies: Giant HII Regions and Super Star Clusters Bulges or Disks in the Centers of Late-type Spirals? Structural Evolution of Galaxies with GOODS and the Ultra Deep Field The Nature of Quasar Host Galaxies: Combining ACS Imaging and VLT Integral Field Spectroscopy Accurately Mapping M31's Microlensing Population The Star Formation History and Metallicity Evolution of M33: A Comprehensive Study of Disk Evolution Determining the Formation Epoch of Dwarf Galaxies Using the HST/ACS Ultra Deep Field Where is the Wind in 1H0707­495? Archival Study of Merger-induced Populations in Early-type Galaxy Cores Can Narrow-line Regions in Luminous AGN Be Enormously Large? The Co-Evolution of Star Formation and Powerful Radio Activity in Galaxies Star Formation in Damped Ly-alpha Galaxies: Testing the Connection with the Lyman Break Population The Masses of the Quasar Relics Constraints on Galaxy Formation Models from Size Evolution of Galactic Disks and Spheroids STIS Follow-up Spectroscopy of Seyfert Galaxies from Cycle 11 near-UV Imaging Survey In-Depth Study of the Antennae with NICMOS and ACS Windows of the Early Universe beyond Redshift 7 NICMOS Observations of A1689 A Snapshot Survey of a Complete Sample of X-ray Luminous Galaxy Clusters from Redshift 0.3 to 0.7 The Assembly History of Disks and Bulges out to z = 1 ACS Observations of the Gravitational Lens B1608+656: Characterizing the Einstein Ring The Astrophysics of the Intergalactic Medium at Intermediate Redshifts Imaging a Protocluster at z = 3.1: Effects of Environment and Evolution on Galaxy Populations in the Early Universe Probing the Nature of Dark Matter Using Cluster Lensing Connecting Mass to Light in the GOODS Fields Discovery of Two Star-forming Galaxies Causing Strong Quasar Absorption Lines Probing the Outer Regions of M31 with QSO Absorption Lines Doubling the Data on the HeII Re-ionization of the Intergalactic Medium UV Confirmation of New Quasar Sightlines Suitable for the Study of Intergalactic Helium SLACR: The Simulation Lyman alpha Comparison Repository Characterizing the Sources Responsible for Cosmic Reionization Properties of Moderate-redshift Galaxy Groups Associated with Gravitational Lenses Morphologies of a New Class of Rest-frame Optical Selected High-redshift Galaxies Confronting HST Observations of Dwarf Spheroidals with Theory The Morphology of Ly-alpha Emission Galaxies at z = 3.11 in the GOODS-S Field


Name

Institution

Type

Title

GO GO GO SNAP GO GO GO AR SNAP GO SNAP GO GO GO AR GO GO GO GO GO GO GO AR SNAP GO SNAP GO GO

10



Christine Jones Smita Mathur Nicholas Morgan Roser Pello Regina Schulte-Ladbeck Tommaso Treu R. Tully Wei Zheng

Smithsonian Institution Astrophysical Observatory Ohio State University Yale University Observatoire Midi-PyrÈnÈes University of Pittsburgh University of California - Los Angeles University of Hawaii The Johns Hopkins University

GO GO GO GO GO GO GO GO

Dark Matter Constraints from the Merging Cluster 1E0657­56 A Combined HST/Chandra Study for Finding the Baryons in the Low-redshift Universe Probing a Damped Lyman-alpha System along Two Lines of Sight Morphology of z ~ 7­10 Galaxies Viewed through Gravitational Telescopes The Connection between Star-forming Galaxies and Low-redshift Quasar Absorption Line Systems Co-Evolution of Spheroids and Black Holes Groups of Dwarf Galaxies: Pools of Mostly Dark Matter? Tracing the Reionization History of Intergalactic Helium out to Redshift 3.8

CYCLE 13: Approved Observing Program s

Galactic Programs The Formation Histories and Dynamical Roles of X-ray Binaries in Globular Clusters Physical Processes in Orion's Veil: A High Resolution UV Absorption Study of the Line of Sight toward the Trapezium Imaging the Chemical Distribution in Type Ia SN Ejecta Toward a Global Understanding of Accretion Physics: Clues from an UV Spectroscopic Survey of Cataclysmic Variables Toward an Accurate Calibration of the Galactic Cepheid P-L Zero Point Multi-color HST Imaging of the GJ 803 Debris Disk Weighing the Most Luminous Main-sequence Star in the Galaxy Accreting White Dwarfs and Neutron Stars near the Galactic Center Resolving OB Binaries in the Carina Nebula, Resuming the Survey Ultraviolet Spectrum of the Binary Millisecond Pulsar J0437­4715 A Snapshot Survey of the Local Interstellar Medium: New NUV Observations of Stars with Archived FUV Observations Planetary Nebulae in the SMC: A Study of Stellar Evolution and Populations in an Extremely Low-metallicity Environment Evolution of Light Echoes of SN 1993J A Mini-Survey of Interstellar Abundances in the Magellanic Clouds Departures from Axisymmetry in Planetary Nebulae Resolving the Thermal Conduction Front in the Bubble S308 The Shadow Echoes of the Unique R Coronae Borealis Star, UW Cen Constraining Models of Galactic Chemical Evolution and Mixing by Measuring the Spatial Variability of D/H in the Interstellar Medium Wind Accretion and State Transitions in the Black Hole Binary Cyg X-1 IY UMa: A Literal Probe of Accretion Disc Structure SAINTS: Supernova 1987A INTensive Survey Prospecting for Rare Elements in the Interstellar Medium The SN 1987A/LMC "Deep Field" STIS Snapshot Survey of Boron Abundances in Early-B Stars On the Evolutionary Status of Extremely Hot Helium Stars: Are the O(He) Stars Successors of the RCrB Stars? Snapshot Survey of SMC Planetary Nebulae Direct Imaging of the Progenitors of Massive, Core-collapse Supernovae Accretion in the Closest Binary Systems Known

Scott Anderson Gary Ferland Robert Fesen Boris Gaensicke Edward Guinan Paul Kalas Anthony Moffat Mark Morris Edmund Nelan George Pavlov Seth Redfield Letizia Stanghellini Ben Sugerman Daniel Welty Matthew Bobrowsky You-Hua Chu Geoffrey Clayton Scott Friedman Douglas Gies Carole Haswell Robert Kirshner James Lauroesch Stephen Lawrence Charles Proffitt Thomas Rauch Richard Shaw Stephen Smartt Danny Steeghs

University of Washington University of Kentucky Dartmouth College The University of Warwick Villanova University University of California - Berkeley UniversitÈ de Montreal University of California - Los Angeles Space Telescope Science Institute The Pennsylvania State University University of Texas at Austin Space Telescope Science Institute Space Telescope Science Institute University of Chicago Space Telescope Science Institute University of Illinois at Urbana - Champaign Louisiana State University & Agricultural & Mechanical College Space Telescope Science Institute Georgia State University Research Foundation Open University Harvard University Northwestern University Hofstra University Catholic University of America Dr.-Remeis-Sternwarte, Bamberg National Optical Astronomy Observatories University of Cambridge Smithsonian Institution Astrophysical Observatory


Name

Institution

Type

Title

CYCLE 13: Approved Observing Program s



11



Todd Tripp Alycia Weinberger Mark Wyatt Silvia Zane John Bahcall Luciana Bianchi Adam Frank Robert Hynes GianLuca Israel Edward Jenkins Charles Keyes Christian Knigge Claus Leitherer Blair Savage Glenn Schneider Roberto Soria Paula Szkody Nolan Walborn Alycia Weinberger Daniel Welty Klaus Werner David Zurek Jay Anderson Thomas Ayres Charles Bailyn Luigi Bedin Andrew Cole Kelle Cruz Richard de Grijs Michael Endl Edward Guinan William Harris Suzanne Hawley Gregory Herczeg Donald Hoard John Huchra Henry Kobulnicky Weidong Li

University of Massachusetts Carnegie Institution of Washington Royal Observatory Edinburgh Mullard Space Science Laboratory Institute for Advanced Study The Johns Hopkins University University of Rochester University of Texas at Austin INAF, Osservatorio Astronomico di Roma Princeton University Space Telescope Science Institute University of Southampton Space Telescope Science Institute University of Wisconsin - Madison University of Arizona University College London University of Washington Space Telescope Science Institute Carnegie Institution of Washington University of Chicago Universitat TÝbingen, Institut fÝr Astronomie und Astrophysik American Museum of Natural History Rice University University of Colorado at Boulder Yale University UniversitÀ di Padova Kapteyn Astronomical Institute University of Pennsylvania University of Sheffield University of Texas at Austin Villanova University McMaster University University of Washington University of Colorado at Boulder California Institute of Technology Smithsonian Institution Astrophysical Observatory University of Wyoming University of California - Berkeley

AR GO GO GO GO GO AR GO GO AR GO GO SNAP GO GO GO GO GO GO GO GO GO GO GO GO GO GO GO GO GO GO GO AR GO SNAP GO GO SNAP

Fundamental Properties of Gas in the Distant Galactic Halo and Leading Arm of the Magellanic Stream Imaging of Ices in Circumstellar Disks Coronagraphic Imaging of eta Corvus: A Newly Discovered Debris Disk at 18 pc Optical Identification of Two Nearby Isolated Neutron Stars through Proper Motion Measurement Observing the Next Nearby Supernova A Search for gamma Cas Analogs at Low Metallicity The Astrophysics of Heterogeneous ("Clumpy") Stellar Outflows A UV Survey of Quiescent Black Holes and Neutron Stars Unveiling the Nature of the 321s Orbital Period Binary RXJ0806.3+1527 A Comprehensive Study of Interstellar Depletions Multi-wavelength Observations of Symbiotic Stars in Outburst A Deep Far-UV Search for the Interacting Binary Population in M80 A Lyman-alpha Snapshot Survey of FBS and SBS Galaxies Origins of the Highly Ionized Gas toward the X-ray Bright BL Lac Object Mrk 421 Solar Systems in Formation: A NICMOS Coronagraphic Survey of Protoplanetary and Debris Disks ACS/HRC Imaging of Two Very Bright Ultra-Luminous X-ray Sources (ULXs) Determining the Instability Strip for Accreting White Dwarfs Critical STIS Spectroscopy and ACS Imagery at the Top of the IMF Spatially Resolved Spectroscopy of HR 4796A's Dust Ring HD 62542: Probing the Bare, Dense Core of an Interstellar Cloud UV Spectroscopy of the Hot Bare Stellar Core H1504+65 A New Class of Bright Ultraviolet Variable Sources in the Globular Cluster NGC 1851 Astrometric and Photometric Study of NGC 6397 for Internal Motions, Dark Binaries, and X-ray Sources The Deep Lamp Project The Core Dynamics of the Dense Globular Cluster NGC 6752 Solving the Problem of the White Dwarf Cooling Sequence End in M4: An Efficient Approach Pre-History of a Starburst: Deep Imaging of IC 10 Resolving a Binary System that Straddles the L/T Transition Our Galaxy's Most Promising Super Star Cluster Candidate, Westerlund 1: Tip of the Iceberg? Detecting the Elusive Low-mass Companion around epsilon Indi Lyman-alpha FUV Observations of the Sun in Time and Effects on Planetary Atmospheres The Most Massive Star Clusters: Supermassive Globular Clusters or Dwarf Galaxy Nuclei? Investigation of M Dwarf Atmospheres Using Archival STIS Data Uncovering the Unknown Ly-alpha Flux in Classical T Tauri Stars A Never-before Explored Phase Space: Resolving Close White Dwarf/Red Dwarf Binaries Star Clusters and Stellar Populations in M81 Resolving the Distance Ambuguity for the Galactic Open Cluster Westerlund 2 A Snapshot Survey of the Sites of Recent, Nearby Supernovae


Name

Institution

Type

Title

GO GO GO AR Rotation of Comet Tempel 1 ACS and WFPC2 Stellar Photometry in the Kepler Mission Target Field Saturn's Auroral Energy Deposition Coordinated with Cassini UVIS The Distribution and Variability of Io's SO2 Atmosphere

12



CYCLE 13: Approved Observing Program s

Kevin Luhman Dean McLaughlin I. Reid Raghvendra Sahai Ricardo Schiavon Nathan Smith Gerardo Vazquez Michael West Przemyslaw Wozniak Charles Alcock Jay Anderson Howard Bond Wolfgang Brandner Thomas Brown Rupali Chandar Robin Ciardullo Gordon Drukier Annette Ferguson Karl Gebhardt Dean Hines Elliott Horch Roberta Humphreys Alex Lobel James Neff Antonella Nota Edward Olszewski Slawomir Piatek Raghvendra Sahai Christopher Sneden Schuyler Van Dyk Alfred Vidal-Madjar

Smithsonian Institution Astrophysical Observatory Space Telescope Science Institute Space Telescope Science Institute Jet Propulsion Laboratory The University of Virginia University of Colorado at Boulder Space Telescope Science Institute University of Hawaii Los Alamos National Laboratory University of Pennsylvania Rice University Space Telescope Science Institute Max-Planck-Institut fÝr Astronomie - Heidelberg Space Telescope Science Institute Space Telescope Science Institute The Pennsylvania State University Yale University Max-Planck-Institut fÝr Astrophysik University of Texas at Austin Space Science Institute University of Massachusetts - Dartmouth University of Minnesota - Twin Cities Harvard University College of Charleston Space Telescope Science Institute University of Arizona New Jersey Institute of Technology Jet Propulsion Laboratory University of Texas at Austin California Institute of Technology CNRS, Institute d'Astrophysique de Paris

GO AR SNAP AR GO GO AR GO SNAP SNAP GO GO GO GO AR GO AR GO AR GO GO GO GO GO GO GO GO SNAP GO AR GO

Searching for the Bottom of the Initial Mass Function Origin of the Globular Cluster Fundamental Plane Ultracool Companions to the Nearest L Dwarfs The Hydrodynamics of Collimated Flow Interactions around Dying Stars Spatially Resolved Mid-UV Spectra of the Centers of Local Group Galaxies An ACS H-alpha Survey of the Carina Nebula Photo- and Spectro-Chemical Evolution Models for Starburst Galaxies Ages and Metallicities of the Intergalactic Globular Cluster Population in Abell 1185 Probing the Dynamics of the Galactic Bar through the Kinematics of Microlensed Stars Systemic Proper Motions of the Magellanic Clouds from Astrometry with ACS: II. Second Epoch Images Improving the Astrometric Calibration of ACS/WFC for the Most Useful Filters Post-AGB Stars in the Halo of M81 NICMOS Differential Imaging Search for Planetary Mass Companions to Nearby Young Brown Dwarfs The Formation Mechanisms of Extreme Horizontal Branch Stars Evolution of Stars and Stellar Systems. I. The Initial Size Distribution of Clusters Determining the Origin of Virgo's Intracluster Stars Theoretical Studies of the Cores of Globular Clusters Probing the Formation and Evolution of M31's Outer Disk and Halo, Part II Central Surface Brightness Profiles of LMC Globular Clusters Imaging Polarimetry of Young Stellar Objects with ACS and NICMOS: A Study in Dust Grain Evolution The Astrophysical Parameters of Very Metal-poor Halo Binaries The 3D Morphology of the Extreme Red Supergiant VY CMa A Critical Test for Radiatively Driven Hot Winds in Cool Stars Are Dust Disks and Circumstellar Gas around Young A Stars Unrelated Phenomena? Current Star Formation in Young, Compact Clusters in the Small Magellanic Cloud The 3-D Shape of the SMC: Is It Tidally Distorted? Space Motions for the Draco and Sextans Dwarf Spheroidal Galaxies When Does Bipolarity Impose Itself on the Extreme Mass Outflows from AGB Stars? An ACS Snapshot Survey Probing the Nucleosynthesis Products of the First Stars The Local Environments of Supernovae Physical Parameters of the Upper Atmosphere of the Extrasolar Planet HD209458b

Solar System Programs

Michael A'Hearn William Borucki John Clarke Lori Feaga

University of Maryland NASA Ames Research Center Boston University Space Telescope Science Institute


Name
GO GO AR GO GO AR GO SNAP GO GO AR AR GO AR GO The Gas Environment of Comet 9P/Tempel 1 During the Deep Impact Encounter Identification of a Magnetic Anomaly at Jupiter from Satellite Footprints An Analysis of HST and IUE Spectra to Investigate the Effects of Space Weathering at Ultraviolet Wavelengths Jupiter's Upper Stratospheric Hazes Probed with Ganymede Titan: Huygens Probe Entry Fireball and UV Seasonal Change Jovian Upper Atmospheric Dynamics and Thermal Structure from STIS Observations of Auroral Emissions Determination of Orbits and Colors for Two New Binaries in the Koronis Asteroid Family Atmospheric Variability on Uranus and Neptune The Moons, Rings and Arcs of Uranus: Discovery and Dynamics The Relative Roles of Volcanism and Sublimation in Supporting Io's Atmosphere Deep Archival Search for Trans-Neptunian Objects Electron Impact Simulations of Io's Atmosphere Recovery of Three Faint Kuiper Belt Objects Discovered with HST The Escape of Oxygen from Mars Fresh Ammonia-ice on Jupiter: The Northern Equatorial Region

Institution

Type

Title

Paul Feldman Denis Grodent Amanda Hendrix Erich Karkoschka Ralph Lorenz Tariq Majeed William Merline Kathy Rages Mark Showalter John Spencer Peter Tamblyn Laurence Trafton David Trilling Jody Wilson Michael Wong

The Johns Hopkins University UniversitÈ de Liege Jet Propulsion Laboratory University of Arizona University of Arizona University of Michigan Southwest Research Institute SETI Institute NASA Ames Research Center Southwest Research Institute Southwest Research Institute University of Texas at Austin University of Pennsylvania Boston University University of California - Berkeley

Large Programs AR GO GO GO GO GO GO GO SNAP GO The Legacy HST Data Set of IGM Spectroscopy The Formation History of Andromeda The Evolution and Assembly of Galactic Disks: Integrated Studies of Mass, Stars, and Gas in the Extended Groth Strip Toward a Comprehensive Understanding of Type Ia Supernovae: The Necessity of UV Observations Testing the Warm-hot Intergalactic Medium Paradigm Unveiling the Progenitors and Physics of Cosmic Explosions The NICMOS Grism Parallel Survey PANS: Probing Acceleration Now with Supernovae The Next Generation Spectral Library Coronagraphic Survey for Giant Planets around Nearby Young Stars

Jill Bechtold Thomas Brown Marc Davis Alex Filippenko J. Howk Shrinivas Kulkarni Matthew Malkan Adam Riess David Silva Inseok Song

University of Arizona Space Telescope Science Institute University of California - Berkeley University of California - Berkeley University of California - San Diego California Institute of Technology University of California - Los Angeles Space Telescope Science Institute European Southern Observatory - Germany University of California - Los Angeles

Treasury Programs GO The HST Survey of the Orion Nebula Cluster

Massimo Robberto

Space Telescope Science Institute

CYCLE 13: Approved Observing Program s



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Status of the Hubble `Two- Gyro' Mode
R. Doxsey, doxsey@stsci.edu

T

hroughout Hubble's 14-year lifetime, the longevity of the gyros used by the Pointing Control System (PCS) has been a concern. Gyros have been replaced on several servicing missions, and there was a 6-week period in 1999 when observations were suspended because the available complement of working gyros dropped below three, the number required for normal operations. The tragic Columbia accident in February 2003 led to the realization that the next planned servicing of Hubble would likely be delayed beyond the projected lifetime of the current complement of gyros. In response, the Hubble project at Goddard Space Flight Center (GSFC) and the Institute began developing the capability to carry out science operations using two rather than three gyros. The availability of such a mode will provide 12 to 18 months of additional observing time with Hubble. In early summer 2004, the technical work required to implement the two - gyro pointing mode is progressing well. The PCS engineers and flight software group at GSFC are well into the design, implementation, and testing of the mode, which requires using other sensor data to replace the `missing' third gyro of normal operations. The replacement data comes from the magnetometers, Fixed Head Star Trackers (FHSTs), and Fine Guidance Sensors (FGSs). The first changes to the flight software, implementing new processing of magnetometer and FHST data, were uplinked to Hubble in May and are performing well. Two further incremental installations are planned, one in the fall and one in January 2005, when full flight test of the two - gyro mode will be conducted. The pointing information from the magnetometers and FHSTs is much less accurate than that from a gyro. As a result, the pointing errors after slews and occultations of the target by the Earth will be much larger than at present: 3 to 10 degrees compared with 5 to 25 arcsec. The major challenge of developing the two - gyro mode is designing and implementing the steps necessary to correct this error to the level where the FGSs can acquire guide stars. Because these steps will have a large impact on the process of scheduling observations, we have been making major changes to our scheduling systems to accommodate the two - gyro mode. The two - gyro mode will increase the pointing jitter of the telescope line of sight. Current estimates are that the jitter pattern will go from a 5 to 7 milliarcsec circle to an approximately 10 by 30 milliarcsec oval. The PCS engineers will be carrying out high-fidelity simulations of the performance of the mode over the summer, which Institute instrument scientists will assess in terms of the scientific impact on the various instrument modes. The Institute has started posting information for observers about the two - gyro mode on the web (http://www.stsci.edu/hst/HST_overview/TwoGyroMode), which we will update regularly. By fall, we will have a handbook on the two - gyro mode, which will cover all the relevant material. Based on the current predictions of gyro lifetime, there is a possibility that we will need to begin using the two - gyro mode sometime during Cycle 14. For this reason, we will modify our procedures for soliciting and selecting proposals to accommodate this possibility. These changes will be reflected in the Cycle 14 Call for Proposals, which will be released in October. Proposers for Cycle 14 will be required to provide information in their Phase I proposals regarding the suitability of their program under two - gyro mode as well as the normal three - gyro mode.



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Scheduling with Two- Gyro Pointing
G. Chapman, chapman@stsci.edu, A . Vick, sherwin@stsci.edu, M. Reinhart, reinhart@stsci.edu, R. Doxsey, doxsey@stsci.edu

A

s a deliberate feature of its design, Hubble can normally view a very large portion of the sky. At any time, the only forbidden area is a 50- degree radius circle around the Sun. Even targets in the ecliptic plane are available ~250 days each year. This design provides a great deal of flexibility, both for observers and for schedulers of the telescope. Observers take advantage of the flexibility by specifying specific orientations for their observations or specific times or time intervals for their observations. Schedulers take advantage of it by distributing observations evenly across the year, avoiding `fat ' or `lean' weeks in the schedule. As the development of two - gyro mode has progressed, the Institute has studied the impact on scheduling, where flexibility will be considerably reduced. While details may change as the mode is completed, the basic implications for scheduling are now understood. In this article, we present a summary of those impacts. Details can be found at http://www.stsci.edu/hst/ HST_overview/TwoGyroMode , which will be updated with new information as it is available. Hubble pointing is remarkably accurate, even when the Fine Guidance Sensors (FGSs) are not used for guiding. The pointing drifts are only ~5 arcsec during the ~40 minutes when a target is occulted by the Earth. The pointing error after a large slew of the telescope is generally < 50 arcsec. These small errors make it relatively easy to acquire, or re -acquire, guide stars. The foundation of Hubble's high pointing precision is the use of three gyros. Loss of one of the gyros will result in much larger pointing errors--of order degrees--after occultations and slews. In the two - gyro mode, the Fixed Head Star Trackers (FHSTs) will compensate for this loss of accuracy, using a step-by- step process (see Figure 1). The need to use the FHSTs for extended periods,

Mode
2 Gyro

M2G Slew wait for second FHST Mop

T2G Mop GS Acq Science

F2G

Fine correction Coarse correction

2 Gyro

Slew

FHST wait for FGS availability

GS Acq

Science

Figure 1: The lower timeline shows the use of FHSTs for three-gyro operations. At most, a short, five-minute FHST update is needed at any time between the end of the slew and the start of the guide- star acquisition. The upper timeline shows the use of FHSTs for two-gyro mode. Magnetometers and two gyros are used for the slew itself (M2G). At the end of the slew, one FHST is used to zero-out the drift rates. When a second FHST is available, it is used to take a map of the star field, to determine and correct the pointing error, which can be as much as 10 degrees. A second map is required, and the FHSTs are used to stabilize the telescope while the guide stars are found. The total time when FHSTs are required is shown with the `T2G' bar.

of order 20 minutes, is the factor that makes scheduling more difficult, and reduces flexibility. The FHSTs do not see the sky in the direction that the telescope is pointing, but instead they point aft, in nearly the opposite direction. There is a requirement that the sightlines of the FHSTs be clear of the Earth prior to the view- direction of the telescope being clear. Satisfying this requirement eliminates many of the observing times available in three - gyro mode (see Figure 2). A narrated animation showing how the sky availability changes through the year is available at http://www.stsci.edu/hst/HST_overview/TwoGyroMode/2GyroMovies. In two - gyro mode, targets at low declinations can be viewed about half the year, generally in one contiguous period. Targets at high declinations, including the continuous viewing zones, will have periodic availability, governed by the 56- day precession of the Hubble orbit. All parts of the sky will be accessible at some time during the year. The number of days per year when any target can be observed in two - gyro mode is about half Continued page 16 that in three - gyro mode (see Figure 3). We are developing graphics for the

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Scheduling from page 15

website to compare the three - and two - gyro cases for specific target locations, to allow observers to take these factors into account when designing future observing programs. As a part of our scheduling studies, we evaluated the impact of some of the parameters changing as the development of the two - gyro mode proceeds. We found that changes in timing and viewing restrictions had only small impacts on the overall scheduling situation. We are confident that the general character of the scheduling situation will be as described here.

DEC-05-2005
90 70 50

Dec (degrees)

30 10 -10 -30 -50 -70 -90 0 50 100 150 200 250 300 350

Solar Avoidance Zone

RA (degrees) DEC-05-2005
90 70 50

Dec (degrees)

30 10 -10 -30 -50 -70 -90 0 50 100 150 200 250 300 350

Solar Avoidance Zone

RA (degrees)
Figure 2: The upper panel shows sky availability for three-gyro mode for a date in December 2005. The only unavailable area is the 50-degree radius region around the Sun. The lower panel shows the sky availability on the same day for the two-gyro mode. Only points with the blue symbols are available for scheduling on this day. Portions of the sky about to pass through the Sun are not available, while those following the Sun are available. The Solar Avoidance zone is also 10 degrees larger than in three-gyro mode.

DEC-05-2005
25 3-gyro 20 2-gyro

Percentage of Sky

15

10

5

0 0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360

Number of Observable Days
Figure 3: Comparison of sky availability in two- and three-gyro modes. Sky availability in two-gyro mode is reduced by about half from the availability in three-gyro mode.



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Advanced Camera for Surveys News
R. van der Marel, marel@stsci.edu Recent science results with the Advanced Camera for Surveys (ACS) continue to show its power for deep imaging and studying the early universe.

O

n March 9th, in the presence of Maryland Senator Barbara Mikulski, Institute Director Steven Beckwith unveiled the Hubble Ultra Deep Field (UDF). It provides the deepest view into the universe to date. The UDF used the ACS Wide Field Channel (WFC) for 400 orbits in the filters F435W, F606W, F775W, and F850LP to reach to about 30 th magnitude and detect more than 10,000 objects.1 The observations were obtained using Director 's Discretionary time, and the data were made available to the astronomical community without a proprietary period. Complementary imaging with the Near Infrared Camera and Multi- Object Spectrometer (NICMOS) further increases the value of this dataset. There is no doubt that the UDF will be a unique resource for a wide range of scientific investigations for many years to come. Information on the UDF and data products is available at http://www.stsci.edu/hst/udf. No distant supernovae were found in the UDF data. By contrast, a team led by A . Riess found 42 supernovae in the data from the ACS Great Observatories Origins Deep Survey (GOODS) program, which is a shallower survey of a wider field than the UDF. The GOODS sample includes six of the seven most distant supernovae known. 2 The apparent brightnesses of the supernovae give cosmologists a way to measure the expansion rate of the universe at different times in the past. The results confirm and refine previous evidence that the cosmological expansion is accelerating due to a strange phenomenon called `dark energy,' the nature of which remains unknown. It could be the energy of empty space, represented by Einstein's cosmological constant, or it could be the effect of a changing energy field dubbed `quintessence.' Future observations with Hubble/ACS will undoubtedly provide further insight into the properties of dark energy and the universal expansion. Observations of distant clusters yield insight into the formation and evolution of galaxies over a broad range of cosmic time. 3 John Blakeslee and his team observed the massive cluster RDCS 1252.9­2927 and inferred that its galaxies formed the bulk of their stars at redshifts z > 3. George Miley and his collaborators uncovered, for the first time, a proto - cluster of `infant galaxies' at z = 4.1. This cluster is so young that its member galaxies are still actively forming stars. These findings are consistent with the cosmological paradigm wherein clusters form from the merger of many sub - clusters in a universe dominated by cold dark matter. However, clusters of galaxies had not previously been observed to exist this early in the age of the universe.

Figure 1: Uranus and Neptune observed by ACS and STIS in a variety of filters. The top panels show the planets in their natural colors, and the bottom panels use an enhanced color representation to highlight atmospheric features. (http://hubblesite.org/newscenter/newsdesk/archive/releases/2004/05/)

A team led by Jean-Paul Kneib used ACS to observe the much nearer galaxy cluster Abell 2218. In their images they found a distant galaxy that is gravitationally lensed by the foreground cluster into a pair of strikingly similar images. 4 The arrangement and color of these images indicate a very distant object with a redshift in the range z = 6.6 to 7.1. Spectroscopy with the Keck Observatory places the redshift of the galaxy in the upper end of that range, which may make it the most distant object yet discovered. Due to the magnification Continued of 25 afforded by the foreground cluster, these observations provide a rare page 18 glimpse of the very early universe. The galaxy, observed when the universe

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ACS from page 17

was barely five percent of its current age, may be typical for the type of young stellar systems that ended the cosmological `dark ages.' M. Brown (Caltech) and his team used the High Resolution Channel (HRC) on ACS to image Sedna, the farthest known object in the solar system, seeking evidence of a satellite. They had recently discovered Sedna at Mt. Palomar and named it after the Inuit goddess of the ocean. Based on the long rotational period inferred from light curves--20 to 50 days--the researchers expected to find a satellite, which could slow Sedna's rotation by tides. However, the ACS images show no sign of a companion, which makes the slow rotation even more interesting. 5 The fact that the HRC image of Sedna is unresolved places an upper limit on the object 's size of approximately three - quarters the diameter of Pluto. In another recently completed study, Erich Karkoschka and his team used ACS and the Space Telescope Imaging Spectrograph (STIS) to image Uranus and Neptune. 6 Figure 1 shows the planets both in their natural color and in an enhanced color representation that highlights atmospheric features. Wider-view ACS images of Uranus also reveal its faint rings and several of its satellites.

Figure 2: Supernova 1987A was the brightest stellar explosion seen since the one observed by Johannes Kepler 400 years ago. A surrounding ring of gas was in place when the star exploded, probably shed some 20,000 years earlier. This recent Advanced Camera for Surveys image shows many bright spots along the ring of gas, like a `string of pearls.' They are produced when a supersonic shock wave unleashed during the explosion slams into the gas ring, at more than a million miles per hour.

Figure 3: Wide Field and Planetary Camera 2 image of one of the most unusual nebulae known in our Milky Way, HD 44179. The nebula is more commonly called the `Red Rectangle' because of its unique shape and color as seen with ground-based telescopes. The star in the center of the Red Rectangle began its life as a star similar to the sun, but is now ejecting its outer layers to produce the visible nebula. The X- shaped structure is due to the bi-conical geometry of the outflow. In a few thousand years, when ultraviolet light from the star makes the nebula fluoresce, the object will become a planetary nebula.

Other stunning ACS images that were recently released show the `string of pearls' caused by Supernova 1987A (Figure 2), 7 the light echo around the star V838 Monocerotis,8 the nearby galaxy NGC 300,9 and the ring galaxy AM 0644­741.10 ACS is not the only camera on Hubble providing remarkable views of the cosmos. Although astronomers use the Wide Field and Planetary Camera 2 (WFPC2) less now than over the past decade, its archive contains many undiscovered treasures. Figure 3 shows a recently released image of the Red Rectangle (HD 44179) as an example.11 As a result of recent ACS calibration work at the Institute, we have delivered new detector quantum efficiency curves and filter throughput curves for the WFC and HRC. The new curves reproduce the observed count rate of spectrophotometric standard stars, with accuracy better than 1% in all broad-band filters and approximately 1% for narrow-band filters. This is an improvement of 1 to 2% with respect to the curves previously used by the ACS pipeline. The pipeline has used the new files to calibrate all ACS data retrieved from the Hubble archive since December 10, 2003. The calibrations only affect the `photometry keyword' section in the header of the science (SCI) extensions of the calibrated FITS files. The new zero-points and the new values of the keywords are also available at http://www.stsci.edu/hst/acs/analysis/zeropoints. The ACS channels have considerable geometric distortion. This is properly taken into account when observers perform photometry on geometrically corrected, drizzled images, such as the drz.fits images produced by the ACS calibration pipeline. However, there might be instances in which it is preferable to perform photometry on flat-fielded but un- drizzled images, namely the flt.fits, also produced by the ACS calibration pipeline. It should be noted that this choice does

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introduce additional complexity. When ACS images are flat-fielded by the calibration pipeline, the resultant flt.fits files are flat if the original sky intensity was also flat. However, because the pixel areas on the sky vary around the field, the relative photometry of point sources in flt.fits files is incorrect. We have made new pixel area maps for WFC and HRC available on the web page http://www.stsci.edu/hst/acs/analysis/PAMS. When these maps are used according to the instructions, relative point- source photometry will be correct across the field. Also, the same photometric zero -points then apply as for drz.fits images. Due to the harsh radiation environment in space, the Charge Transfer Efficiency (CTE) of CCD detectors on Hubble degrades slowly with time. We make regular calibration observations to monitor this degradation for the ACS CCDs. A . Riess and J. Mack analyzed data of the globular cluster 47 Tuc obtained with the WFC in March 2003, August 2003, and February 2004. The data are consistent with a slow CTE degradation that is approximately linear with time. To read out the charge in a CCD, it has to be sequentially shifted in two separate directions, called `parallel' and `serial,' to an amplifier in the corner of the chip. Charge can be lost in either of the two phases. Photometric losses due to imperfect parallel CTE increase with decreasing stellar flux and decreasing background surface brightness. The photometric losses decrease with increasing aperture size, probably due to the ability of large apertures to recapture a fraction of the trapped and emitted charge. There is no evidence for significant serial CTE losses at the present time. A time - dependent global fitting formula is available that allows correction for the parallel CTE losses. For details, see ACS ISR 04-06, available from http://www.stsci.edu/hst/acs/documents/isrs. M. Mutchler and A . Riess (ACS ISR 04-04) analyzed how the CTE depends on detector operating temperature. This study was motivated by the expectation that an aft- shroud cooling system would be installed during Servicing Mission 4, which would have allowed a lowering of the present operating temperature to mitigate the impact of CTE . However, even at the present operating temperature they do not expect CTE degradation to be a showstopper for ACS science. They have used the correction formulae derived from calibration programs to predict the future quality of the parallel CTE . Although such extrapolations are uncertain, they expect that the vast majority of ACS science applications will retain a flux measurement precision of a few percent or better towards the end of the decade. F. Boffi and her collaborators performed a study of possible contamination buildup on ACS. They performed repeated observations of the star cluster NGC 6681 in ultraviolet light with both the HRC and the Solar Blind Channel (SBC). The results indicate that ACS does not suffer from ultraviolet performance degradation due to contamination. For filters F220W, F250W, and F330W, any sensitivity changes must be less than one percent. By contrast, WFPC2 can show tens of percent degradation of ultraviolet throughput over the course of a month (after which decontaminating the instrument restores the original throughput). These results are not unexpected, since unlike the WFPC2, the ACS does not have a cold external window. R . Gilliland studied the gain, full-well depth, and linearity of the ACS CCDs (ACS ISR 04-01). The CCDs on ACS can be operated at multiple gain settings. Analysis of calibration and science data yielded corrections to the various gain settings of order 1% or less with respect to the default values. Maps of the full-well depth (where saturation sets in) for both HRC and WFC show spatial variations in excess of 10%. When operated with gains that fully sample the full-well depth, and if one sums over pixels that have been bled into as a result of over- saturation, the CCDs remain perfectly linear (to better than 0.1% in relative counts) to well beyond saturation. J. Walsh and his collaborators at the Space Telescope European Coordinating Facility (ST-ECF) analyzed the fringing of the ACS CCD detectors (ACS ISR 03-12). Fringing is only a small problem for observations using filters with relatively wide transmission curves. However, it can significantly affect grism observations at red wavelengths. The fringing of CCD detectors occurs because of interference between the incident light and the light reflected at the internal interfaces of the thin layers of the CCD chip. Knowing the construction of the CCD--the layer materials, the variation of their refractive indices variation with wavelength, and their thicknesses--the ST-ECF group calculated the resulting fringe amplitude using geometrical optics. With a simple model for the thickness, they obtained good fits to a series of narrow-band flat fields at wavelengths from 7000 to 10000 å , which were obtained during ACS ground testing at Ball Aerospace. By applying the model maps of the layer thicknesses to ground or in- orbits flats, the observed fringing in ACS can be reduced by approximately a factor of four, to the level of a few percent rms. In the first few years of ACS operation, the filter wheels did not always rotate to their nominal position and were sometimes off the mark by one motor step. This was not generally a problem, except for those filters that have small blemishes. A blemish produces an out- of-focus feature in the flat field, which changes position if the filter Continued page 20 wheel does not rotate to its nominal position. For a few filter combinations,

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this led to flat-fielding errors that could exceed one percent over a small part of the field of view. We have now addressed this problem through an upgrade to the flight software, which is responsible for all on-board commanding of the instrument. Tests with the new software indicate that the filter wheel is now correctly positioned at all times. The coronagraphic modes on HRC have presented another problem for flat-fielding. The coronagraphic spots drift randomly over a region that is some five pixels across. This necessitates the construction of a flat field that is tailored to each specific observation date. To enable this, we decompose the flat field into a static part that is applied by the calibration pipeline and a spot flat that must be applied manually. The spot flats are available from http://www.stsci.edu/ hst/acs/analysis/reference_files/hrc_coron_spotflat_list.html. To apply the spot flat, one must know the spot position, which is monitored regularly and is also tabulated on the aforementioned web page. The amount of hard disk storage space required for ACS images is considerable. We are therefore investigating ways to achieve significant data compression. Several years ago, Rick White and Perry Greenfield proposed a method of compressing images as floating point arrays, which can achieve considerable size reduction, due to the fact that it is not lossless. In essence, the compression gain is achieved by not storing information that is far below the image noise level. Of course, such methods raise the concern that astronomically important information might be lost. To address this concern, Colin Cox performed an analysis of a variety of ACS images, both with and without compression (ACS ISR 04-02). In the examples tested, compression ratios of about six were obtained with no significant information loss. We are investigating the possibility of making this compression algorithm available to users. As always, consult the ACS web page at http://www.stsci.edu/hst/acs/ for the latest information. For questions, send email to the STScI Help Desk at help@stsci.edu.
1 2 3 4 5 6 7 8 9 10 11

http://hubble.stsci.edu/newscenter/newsdesk/archive/releases/2004/07/ http://hubble.stsci.edu/newscenter/newsdesk/archive/releases/2004/12/ http://hubble.stsci.edu/newscenter/newsdesk/archive/releases/2004/01/ http://hubble.stsci.edu/newscenter/newsdesk/archive/releases/2004/08/ http://hubble.stsci.edu/newscenter/newsdesk/archive/releases/2004/14/ http://hubble.stsci.edu/newscenter/newsdesk/archive/releases/2004/05/ http://hubble.stsci.edu/newscenter/newsdesk/archive/releases/2004/09/ http://hubble.stsci.edu/newscenter/newsdesk/archive/releases/2004/10/ http://hubble.stsci.edu/newscenter/newsdesk/archive/releases/2004/13/ http://hubble.stsci.edu/newscenter/newsdesk/archive/releases/2004/15/ http://hubble.stsci.edu/newscenter/newsdesk/archive/releases/2004/11/

The Heart of the Trifid Nebula

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he Trifid Nebula, cataloged by astronomers as Messier 20 or NGC 6514, is a well-known region of star formation lying within our own Milky Way Galaxy. It is called the Trifid because the nebula is overlain by three bands of obscuring interstellar dust, giving it a trisected appearance as seen in small telescopes. The Trifid lies about 9,000 light-years (2,700 parsecs) from Earth, in the direction of the constellation Sagittarius. Image Credit: NASA , ESA , and The Hubble Heritage Team (AURA/STScI)



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M

ULTI

DRIZZLE in the Hubble Archive Pipeline
A . M. Koekemoer, koekemoe@stsci.edu

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any Hubble observers divide their observations into multiple exposures to facilitate the rejection of cosmic rays, which can affect a large number of CCD pixels. Furthermore, they often use the technique of "dithering," whereby multiple exposures are obtained at slightly different pointings, to provide better subsampling of the Hubble point- spread function and to move bad pixels to different locations on the sky. Observers can combine dithered exposures into a single image using the DRIZZLE program (Fruchter and Hook 2002), which was implemented for the Advanced Camera for Surveys (ACS) by means of the PYD RIZZLE script. However, PYDRIZZLE focuses primarily on image registration and combination and does not directly address cosmic-ray rejection. We developed the MULTIDRIZZLE script (Koekemoer et al. 2002) to provide a single, automated means of aligning images, performing cosmic-ray rejection, and producing a final, cleaned, combined image using Drizzle. MULTIDRIZZLE is available to observers within IRAF/STSDAS, and, as of August 2004, it is also now incorporated into the Hubble archive pipeline. The initial pipeline Figure 1: An example of the automatically cleaned MULTIDRIZZLE product, implementation produces cleaned, combined images for all for a four-exposure dithered observation of the nearby galaxy NGC 4594. ACS associations, which are defined as groups of The top panels show the final, full-frame drizzled and weight images (left exposures obtained using dither patterns or CR- SPLIT and right, respectively). The bottom left panel shows a close-up of the specifications in the Phase II observing file. output image from MULTIDRIZZLE, while the bottom right panel shows the MULTIDRIZZLE is run on images that have passed through same region including all of the accumulated cosmic rays originally the essential steps of calibration, which include bias present in the exposures. subtraction, flat fielding, and dark current correction. Given a set of input exposures, MULTIDRIZZLE carries out the following steps: · Calculate and subtract a background sky value for each exposure; · Search for additional bad pixels in each exposure, which are occasionally not flagged during calibration; · Determine shifts from the coordinates in the image headers and apply these shifts in drizzling all the exposures onto a series of separate output images that are registered on a common grid; · Use the drizzled exposures to create a first-pass cleaned image, which is essentially a sigma- clipped median image; · Transform the first-pass, clean, median image back to the frame of each original input exposure; · Compare each input exposure with the clean image to create a cosmic-ray mask; · Use DRIZZLE to combine all the input exposures, weighted by their cosmic-ray masks, thereby creating a final cleaned output image. Figure 1 shows an example of the type of output produced by M ULTIDRIZZLE, run with all its default parameters on a four- exposure dithered observation of the galaxy NGC 4594. The image demonstrates the good quality of the automated cosmic-ray removal within MULTIDRIZZLE, along with the accuracy of the registration obtained from the image headers. The initial implementation of M ULTIDRIZZLE in the Hubble archive pipeline, for the ACS Wide Field Channel, High Resolution Channel, and Solar-Blind Channel, can be expected to provide useful images for datasets where the standard recommendations on dithering were followed. These recommendations include obtaining at Continued least four images of comparable exposure time and the use of a dither page 22

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pattern or CR- SPLIT to ensure that the exposures are formally associated within the pipeline system. MULTIDRIZZLE will also combine associations with fewer than four exposures, but due to the high rate of incidence of cosmic rays on the CCD pixels, such datasets will generally contain some pixels that are unrecoverable because they have cosmic rays in all the exposures. If observers request the calibrated output products for ACS associations, then they will automatically receive the cleaned MULTIDRIZZLE output image along with all the separate exposures and other related files. The output image is drizzled to the same pixel scale as the channel that was used to obtain the data and is generally oriented with north toward the top. There are some cases where observers may wish to re -run MULTIDRIZZLE themselves on the images, perhaps using slightly different parameters in order to produce images that are optimal for particular kinds of science. For example, they may wish to use a finer pixel scale or a different orientation. This can be easily achieved by running M ULTIDRIZZLE within their own IRAF/STSDAS environment once they have received the data. We are continuing efforts to generalize MULTIDRIZZLE to other Hubble instruments and to add new capabilities. The off-line version available within IRAF/STSDAS is tested for both ACS and Wide Field and Planetary Camera 2 data; we will eventually include Space Telescope Imaging Spectrograph and Near Infrared Camera and Multi- Object Spectrometer datasets. Other enhancements--for example, the ability to empirically refine the header-based shifts--are also underway and may eventually be incorporated into the pipeline as well as the IRAF/STSDAS off-line version. We hope that the initial implementation of M ULTIDRIZZLE for ACS associations in the Hubble pipeline constitutes a substantial enhancement to the scientific quality of the pipeline products.

References Fruchter, A . S. & Hook, R . N. 2002, PASP 114, 144 Koekemoer, A . M., Fruchter, A . S., Hook, R . N., & Hack, W. 2002, HST Calibration Workshop, ed. S. Arribas, A . M. Koekemoer, & B. Whitmore (STScI: Baltimore), 337 Koekemoer, A . M., et al. 2004, HST Dither Handbook, V3.0 (STScI: Baltimore)

Space Phenomenon Imitates Art

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his image resembling Vincent van Gogh's painting, "Starry Night," is Hubble's latest view of an expanding halo of light around a distant star, named V838 Monocerotis (V838 Mon). This Hubble image was obtained with the Advanced Camera for Surveys on February 8, 2004. The illumination of interstellar dust comes from the red supergiant star at the middle of the image, which gave off a flashbulb-like pulse of light two years ago. V838 Mon is located about 20,000 light-years away from Earth in the direction of the constellation Monoceros, placing the star at the outer edge of our Milky Way galaxy. Image Credit: NASA and The Hubble Heritage Team (AURA/STScI)



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Ultra- Deep Fields from Hubble to Webb
M. Stiavelli, mstiavel@stsci.edu

O

n March 9, 2004, the Hubble Ultra Deep Field (HUDF) data were released to the astronomical community. Within 48 hours of the release, the first science paper based on these data appeared on the astrophysical preprint server. What can we learn from the HUDF that might apply to similar observing programs that might be planned for the James Webb Space Telescope (JWST)? From a scientific point of view, the HUDF shows that objects at redshift z > 5 begin to display substructures when observed with sufficient sensitivity. There are also indications that galaxies at redshift z > 6 are rarer than expected on the basis of a simple extrapolation to higher redshifts, at constant co-moving number density, of the luminosity function at z = 3. Thus, JWST must be capable of very sensitive observations over a wide field of view to find the galaxies at significantly higher redshift than the limit of the HUDF. Indeed, the HUDF result vindicates the present design for JWST and its instruments. The present field of view of the Near Infrared Camera (NIRCam) is about the same as that of the Advanced Camera for Surveys (ACS). A smaller field of view for NIRCam would reduce significantly the efficiency of JWST to observe deep fields. High sensitivity has always been and remains a very important requirement for JWST. The HUDF was perhaps the most demanding Hubble observation to date and provides technical lessons for JWST. The final HUDF images from ACS were obtained by combining up to 288 individual images. The ACS Wide Field Camera has a geometric distortion such that the pixels are diamond shaped and change in area by ~10%. The HUDF team profited from an excellent characterization of the geometric distortion of the ACS, which was carried out by J. Anderson and I. R . King for other scientific reasons. By incorporating this characterization in a custom version of drizzle, the HUDF team recovered a point- spread function (PSF) in the final images that is very close to the theoretical Figure 1: A comparison of the Hubble Ultra Deep Field (left panel) with a simulated image of an ultra limit obtained by convolving the diffractiondeep field with JWST (right panel, courtesy of Myungshin Im). limited width with the original pixel size of ACS. In particular, the registration of so many individual images did not result in additional broadening of the PSF. The HUDF images, obtained from both the ACS and the Near Infrared Camera and Multi-Object Spectrometer (NICMOS), show an increase in depth compared to past observations that follows the theoretical limit (given by the square root of the total exposure time). Neither ACS nor NICMOS had an original performance requirement to obtain exposures of 300,000-second duration without degradation in signal-to-noise. The fact that they do so is very promising for JWST, and indicates that a well-calibrated instrument can follow the theoretical curve well beyond normal expectations and levels that are testable on the ground before launch. The Institute produced special, high-precision bias, dark, and flat-field calibrations for the ACS to support the HUDF. The large number of reference files needed to produce these calibrations had no impact on observing efficiency, because Hubble can obtain bias and dark files in parallel to other observations. Clearly it will be important to be able to do the same with JWST. In the HUDF, the faintest galaxies contribute only 0.025% to the local sky intensity. At this level, flat-field residuals become the dominant systematic error. For the sky flat fields, the HUDF team found that only the data themselves could provide sufficiently accurate information for flat fielding. A critical step in this process was obtaining data at two different Continued page 24 orientations, which revealed the presence of residual effects that were orientation

HST

JWST



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UDF from page 23

dependent. For Hubble, the contributions from various scattered-light components at very faint levels are such that a sky image with even slightly different pointing, or obtained at a slightly different time, will be slightly different from those at the initial orientation. This effect limits the ultimate accuracy of flat-fielding shallower data sets, but it was not a problem for the HUDF because the data were sufficiently deep to provide adequate flat fielding on their own. The final sky flatness for the HUDF is better than 1% rms. The longer period of the JWST orbit and its distance from the Earth and the Moon may provide a more stable sky. In this case, it may be convenient to obtain sky flat-fielding images in parallel with science observations with other instruments, although it is too early to know whether this will be convenient or necessary. We anticipate that `self ' sky flats will become increasingly important at longer infrared wavelengths (>3 microns), where the level of the zodiacal light increases significantly. While obtaining data for the primary ACS field, the HUDF observations also obtained (in parallel data on two fields with NICMOS) the two deepest near-infrared observations ever made, and on two fields with Wide Field and Planetary Camera 2 (through the F300W filter) the two deepest ultraviolet images ever obtained. By investing one million seconds of ACS time, we obtained 3.5 million seconds of data on the sky by operating all Hubble instruments in parallel. Clearly, it would be highly desirable to obtain such leverage by parallel observations with JWST. The multiplier could be a factor of four if all instruments could be operated in parallel. However, because of the high costs, such parallel science capabilities are not currently supported on JWST. The glimpse of the z > 6 universe revealed by the HUDF reinforces the need for a JWST Deep Field, to push the study of galaxy formation and evolution to higher redshifts by probing longer wavelengths. JWST will also be able to extend to lower luminosities the study of z > 6 galaxies, to get a more complete view of the galaxy population at the end of the cosmic Dark Age.

Progress on the JWST Primary Mirror
M. Clampin, JWST Observatory Project Scientist, mark.clampin@nasa.gov

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Figure 1: The primary mirror segment of the JWST Engineering Demonstration Unit, mounted for machining at Axys Technologies.

he James Webb Space Telescope (JWST) Optical Telescope Element (OTE) continues to meet its schedule goals as the program begins fabrication of the flight optics. In the last six months we successfully passed mission and OTE requirements reviews, which were key milestones for the project. Following the selection of beryllium technology for the JWST primary mirror segments, the Mirror Review Board recommended a number of additional tests on the demonstration mirror to provide early mitigation of outstanding concerns regarding beryllium. Foremost amongst these tests was a demonstration that the required mirror segment surface error of 20 nm could be achieved on a timescale compatible with the fabrication schedule for the flight mirror. Tinsley and Ball Aerospace were able to meet this additional milestone with the Advance Mirror System Demonstrator, providing a robust demonstration that the technology and process are in place for fabricating the flight-mirror segments. The JWST schedule calls for an Engineering Demonstration Unit (EDU) to serve as a pathfinder for producing the eighteen flightmirror segments and build confidence that the critical flight-mirror production pipeline will remain on schedule. Brush-Wellman, which fabricates the mirror blanks using a process called hot isostatic pressing (HIP), recently completed the EDU mirror billet and shipped it to Axys Technologies for the first phase of mirror-blank machining. Figure 1 shows the EDU unit on its mount, ready for machining.



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News from the Multi-mission Archive at STScI (MAST)
R. Somerville, somerville@stsci.edu, on behalf of the MAST team

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s of May 1, 2004, MAST contained 19 terabytes of data. The average ingest rate from February through April was 16.8 gigabytes/day, and the average daily retrieval rate over this period was 59.8 gigabytes/day. There were over 22,000 web - searches of MAST holdings per month in March and April 2004. Median retrieval times have dropped to less than two hours since the installation of DADS 10.2, in December 2003, and in early May 2004, the median retrieval time was under 30 minutes! DADS Upgrade News The most recent DADS release occurred on June 1 & 2, 2004. We have completely redesigned the ingest function, with no direct impact to users. A new feature enables users to retrieve proprietary data to the staging disk. We encourage users to take advantage of this feature, especially if they have slow or unreliable connections. This release also features improved Secure Shell File Transfer Protocol (SFTP) transfers, with better error handling. If SFTP is not functioning properly, we can now redirect the requested data to a CD or DVD or to staging. We have improved some messages to users on the web status page to make them easier to understand. Ultra Deep Field Release

The Ultra Deep Field (UDF) data from Hubble were released on March 9, 2004 (see http://www.stsci.edu/hst/udf for a description of the UDF program). The raw data and High-Level Science Products (HLSP), including object catalogs, are available at the Institute, the Space Telescope European Coordinating Facility, and the Canadian Astronomy Data Centre, through http://archive.stsci.edu/prepds/udf/udf_hlsp.html. Raw data may also be requested on DVD through MAST. New, Streamlined HLSP Guidelines Cycle 13 General Observers, especially PIs of Treasury or Large Programs, should note that we have simplified and streamlined the guidelines for contribution of HLSPs to MAST. The new guidelines may be found at http://archive.stsci.edu/hlsp_guidelines.html . Atlas of Re-calibrated HST/FOS Spectra of Active Galactic Nuclei and Quasars An atlas of recalibrated spectra of active galactic nuclei and quasars from the Faint Object Spectrograph, produced by Evans and Koratkar, is now available as a MAST HLSP (http://archive.stsci.edu/prepds/fos_agn/index.html ). New, Improved Tools at MAST We have made improvements to several of our tools at MAST (check the MAST search toolbox at http://archive.stsci.edu/mast_search_toolbox.html ). The Spectral Data Coplot Utility (http://archive.stsci.edu/mast_coplot.html ) now has the option of displaying the average of `like' spectra. Spectra from the Far Ultraviolet Spectroscopic Explorer are now included in the MAST Scrapbook (http://archive.stsci.edu/scrapbook.php ). The VizieR search form now offers the ability to search on astronomical terms defined by NASA's Astronomical Data Center, as well as to perform keyword searches on author 's name, catalog title, and catalog description. This allows searching on many object classes. A new version of VOPLOT is now accessible from the MAST search results pages. VOPLOT is a tool for visualizing astronomical data. VOPLOT is developed in JAVA , and acts on data available in the VOTable format. For more information, see http://vo.iucaa.ernet.in/~voi/voplot.htm. New VOPLOT features include: · Projection maps for sinusoidal, Aitoff, and Mollweide Projections · Operator calculator for easy creation of new columns and filters · Ability to plot data on reverse X and Y axes · Reorganization of user interface · Bug fixes
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MAST from page 25

The Virtual Observatory at MAST A new web page at http://archive.stsci.edu/vo/ discusses MAST participation in the National/International Virtual Observatory and provides useful VO -related links. Check this site for updates about our ongoing activities. A more general site devoted to VO activities at the Institute is http://nvo.stsci.edu/. Some recent VO -related developments at MAST are: · All MAST mission searches can now be returned in the VOTable format. · Hubble previews are available via the VO Simple Image Access Protocol (SIAP). · Ultraviolet Imaging Telescope image and preview data are also available via SIAP. · GOODS Version 1 HLSPs are available via SIAP. · Early release observations from the Galaxy Evolution Explorer and some Hubble datasets (the HDF North and South, GOODS, and the UDF) are now incorporated in a SKYQUERY prototype (http://www.skyquery.net/). SKYQUERY is a prototype of a federated database application, implemented using a set of interoperating Web services. This is a demonstration of how typical applications in the Virtual Observatory may look. · MAST holdings can now be searched simultaneously with data from many other surveys and missions through the Data Inventory Service (DIS) (http://heasarc.gsfc.nasa.gov/ vo/data-inventory.html), developed for the National Virtual Observatory and hosted at the High Energy Astrophysics Science Archive Research Center. The survey and mission data in the DIS currently include the Sloan Digital Sky Survey, the Two Micron All Sky Survey, the ROSAT All Sky Survey, Hubble, Chandra, and the Energetic Gamma Ray Experiment Telescope.

Hubble Traces Firestorm of Star Formation

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he Large Magellanic Cloud (LMC), located only 160,000 light-years from Earth, is the nearest galaxy outside the Milky Way in which stars are actively being formed. With its high resolution, the Hubble Space Telescope can study details of star formation in the LMC as easily as ground-based telescopes can study stellar formation within our own Milky Way galaxy. N11 is the second largest star-forming region in LMC. It is only surpassed in the size and activity by "the king of stellar nurseries," 30 Doradus, located opposite N11. Image Credit: NASA , ESA , the Hubble Heritage Team (AURA/STScI), and HEIC



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Hubble Fellowship Program
M. Fall, fall@stsci.edu

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ubble Fellowships are awarded annually to outstanding young scientists engaged in research related to the Hubble mission. The research may be theoretical, observational (space -based or ground-based), or instrumental. The Fellowships provide three years of salary and other support at U.S. host institutions of the Fellows' choice, subject to a maximum of one new Hubble Fellow per institution per year. A selection committee met at the Institute in January 2004 to review more than 130 applications for Hubble Fellowships to start in September 2004. The new Fellows are listed in the table shown below. Hubble Fellows present the results of their research each year in a Hubble Fellows Symposium at the Institute. The most recent Symposium was held on December 9 & 10, 2003. We plan to select approximately twelve new Hubble Fellows in winter 2004/5 for positions to start in fall 2005. The announcement of opportunity, available at http://www.stsci.edu/ stsci/hubblefellow/ao.html , provides instructions for the application process.

2004 New Hubble Fellows
Name
Gaspar Bakos Edo Berger Joseph Hennawi Kelsey Johnson Lisa Kewley Anjum Mukadam Masami Ouchi Hiranya Peiris Scott Sheppard Aristotle Socrates Joshua Winn Zheng Zheng

Host Institution
Center for Astrophysics Carnegie Observatories University of California at Berkeley University of Wisconsin University of Hawaii University of Washington Space Telescope Science Institute University of Chicago Carnegie Department of Terrestrial Magnetism Princeton University Center for Astrophysics Institute for Advanced Study

Supernova Blast in Nearby Galaxy

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he nearby dwarf galaxy NGC 1569 is a hotbed of vigorous star birth activity which blows huge bubbles that riddle the main body of the galaxy. The galaxy's "star factories" are also manufacturing brilliant blue star clusters. This galaxy had a sudden onset of star birth about 25 million years ago, which subsided about the time the very earliest human ancestors appeared on Earth. Image Credit: ESA , NASA and P. Anders (GÆttingen University Galaxy Evolution Group, Germany)



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Hubble Meets the Giant Screen
J. Stoke, stoke@stsci.edu, P. Stanley, pstanley@stsci.edu

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s the first high-resolution images from the Advanced Camera for Surveys (ACS) were displayed in the Institute's Office of Public Outreach, we began to ponder the question of how to best display them to the public. A single ACS image contains an IMAX- screen's worth of pixels, and we planned to produce some truly immense pictures by making mosaics of ACS images. But IMAX? Was it time for the Hubble Space Telescope to meet the biggest of movie screens? We had never seriously considered working in this large -format medium, because its production usually costs hundreds of thousands of dollars per minute, far more than our budget could manage. We came up with a rather unconventional idea: a series of trailer-length (under three minutes) explorations of the universe as seen by Hubble, to be created almost entirely in-house and offered to the large -format theater community as a public service, at very low cost. With the help of the Maryland Science Center and D. Keighley of DKP/70MM Productions, a subsidiary of IMAX Corporation, we created the series pilot production: " Hubble : Galaxies Across Space and Time." DKP/70MM Productions donated the services and materials to create the negative and first print from our digital frames; without their generous contribution, we could not have proceeded. Would large -format theaters support Figure 1a and b: The audience watches the award-winning IMAX film, the concept of adding a Hubble short "Hubble: Galaxies Across Space and Time," which won Best Short Feature to their schedules? at the recent LFCA annual conference in Hollywood. If the response of the Large Format Cinema Association (LFCA) members is any indicator, the answer is a resounding YES! "Hubble: Galaxies Across Space and Time" was selected as the Best Short Feature at the recent LFCA annual conference in (where else?) Hollywood, in April 2004. We debuted the feature at the Maryland Science Center in March, and it will be running there throughout the summer. It is also now showing at the Reuben H. Fleet Science Center in San Diego. Initial feedback from a San Diego console operator at the Planetarium/IMAX dome, when asked about audience reaction, was " The public is responding well to the Hubble footage. Their mouths are hanging open." That was our goal! Jaws agape at the splendor of the universe! We are developing a limited number of prints of our pilot feature while we consider feedback from viewers and theaters on the value of the program. We are also assessing the sustainability of the series by seeking corporate sponsors to subsidize the production costs for new titles. We have received inquiries from many theaters across the country, with some indicating a willingness to pay the relatively modest cost (~$1500) for their own print. That is a real show of support!



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It Really IS an Honor to Be Nominated
S. Kakadelis, stratis@stsci.edu, P. Stanley, pstanley@stsci.edu

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any of us have rolled our eyes when hearing an Oscar nominee declare, "It 's just such an honor to be nominated." Well, the Institute has joined those ranks! Our HubbleSite was nominated for a prestigious Webby Award in the science category. Presented by the International Academy of Digital Arts and Sciences, a Webby Award is the leading international honor for achievement in web technology, creativity, and individual achievement. Sites undergo a rigorous six-month, three -tiered evaluation process against six criteria on the way to winning the coveted Webby Award. The fact that HubbleSite made it to the final list of five nominees in the science category is a big honor in the Web world. While we did not win, we can take pleasure in noting that both the `academy ' winner (Exploratorium at http://www.exploratorium.edu) and the `people's voice' winner (How Stuff Works at http://www.howstuffworks.com) both link to HubbleSite (http://hubblesite.org)!

Figure 1: HubbleSite was honored by a Webby Award nomination in the science category.

Measuring Hubble's Impact in the Classroom
B. Eisenhamer, bonnie@stsci.edu, D. Weaver, dweaver@stsci.edu

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ew York City public schools and Penn State University are among the 312 U.S. school districts and 200 colleges and universities using the Institute's Amazing Space online curriculum- support materials as an educational resource. This finding comes from the first phase of an impact study being conducted by the formaleducation team of the Office of Public Outreach. The results so far are based on information compiled from Web -based research. The formal- education team initiated the study to determine which educational institutions are using Amazing Space materials and how they are being used. Amazing Space is a space - science education program designed for K­12 students and teachers, which offers both hard copy and interactive, Web -based activities. Visit us at http://amazing- space.stsci.edu/ . Educators in all 50 states are using the curriculum- support material in a variety of ways. One of the largest school districts, Montgomery County in Maryland, has recently incorporated Amazing Space's Hubble Deep Field Academy Activity into its eighth- grade science curriculum. Other school districts are linking Amazing Space to state content standards. At the university level, in colleges of education, professors are using Amazing Space activities to train teachers on the principles of integrating technology into science curricula. They also are matching state education standards to Amazing Space activities in their education courses. In the study 's next phase, the formal- education team will pursue other methods of research to identify the use of Amazing Space activities, including interviewing educators across the U.S. The team is searching for answers to the following questions: How did educators discover Amazing Space activities? What were the evaluation criteria for selecting Amazing Space? Do the educators plan on continuing to use Amazing Space? Are they interested in partnering with the formal- education team to provide additional information about student learning?

Figure 1: Amazing Space provides curriculum- support materials for primary and secondary education. (http://amazing- space.stsci.edu/)



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May Symposium 2004
M. Livio, mlivio@stsci.edu

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he Institute hosted the annual May Symposium May 3­6, 2004. The title of the symposium was "Planets to Cosmology: Essential Science in Hubble's Final Years." Approximately 120 participants attended. As the title implies, the goal was to attempt to identify scientific topics that should be given high priority in Hubble's observation program during the time remaining before the telescope ceases operation. Accordingly, in contrast to the more scientifically focused meetings of previous years, this year 's symposium covered a broad range of astronomy. The agenda consisted of sessions devoted to general subjects: planets, star formation, super-massive black holes, the interstellar and intergalactic media, galaxy formation and evolution, the Hubble Ultra Deep Field, and dark energy. In addition to the 32 invited and contributed talks, this symposium included a special panel discussion, in which five experts presented and discussed their perspectives on science priorities for the coming few years. The two topics that stood out are arguably the two most intriguing questions in astrophysics today: (1) what is the nature of the mysterious dark energy that propels the universe into accelerating expansion? and (2) does extraterrestrial life exist? Hubble is making--and can continue to make--unique and important contributions on both of these questions. Currently, Hubble observations of supernovae at redshift z > 1 place the most meaningful constraints on the equation of state of dark energy. Specifically, the observations show the equation of state is consistent with that expected from Einstein's cosmological constant. Future observations can decrease the current error bars on the parameters of the equation of state by a factor of two. Only Hubble is capable of accurately measuring supernovae in the critical range of redhshifts, where the transition between decelerating and accelerating expansion occurred. This will be true for at least another seven years, until JWST is operating. Hubble is also the only telescope now capable of determining the atmospheric composition of extrasolar planets. For the transiting planet around HD 209458, Hubble has already detected the presence of sodium, hydrogen, and oxygen. Because the atmosphere is an important factor in a planet 's potential habitability, these measurements are landmark first steps toward the goal of detecting life outside the solar system. The future servicing of Hubble is becoming more realistic. The 2004 May Symposium displayed a strong case for continuing operations based on the outstanding science value of Hubble observations yet to be made.



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Farthest Known Galaxy in the Universe

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n international team of astronomers may have set a new record in discovering what is the most distant known galaxy in the universe. Located an estimated 13 billion light-years away, the object is being viewed at a time only 750 million years after the big bang, when the universe was barely 5 percent of its current age. The primeval galaxy was identified by combining the power of NASA's Hubble Space Telescope and CARA's W. M. Keck Telescopes on Mauna Kea in Hawaii. These great observatories got a boost from the added magnification of a natural "cosmic gravitational lens" in space that further amplifies the brightness of the distant object. Image Credit: ESA , NASA , J.-P. Kneib (Caltech/Observatoire Midi-PyrÈnÈes) and R . Ellis (Caltech)

Contact STScI:
The Institute's website is: http://www.stsci.edu Assistance is available at help@stsci.edu or 800-544-8125. International callers can use 1-410-338-1082. For current Hubble users, program information is available at: http://presto.stsci.edu/public/propinfo.html. The current members of the Space Telescope Users Committee (STUC) are: Debbie Elmegreen (chair), Vassar College, elmegreen@vassar.edu David Axon, RIT Martin Elvis, Harvard-Smithsonian Eric Emsellem, CRAL Karen Meech, IfA Peter Nugent, LBL C. Robert O'Dell, Vanderbilt U. Regina Schulte-Ladbeck, U. Pittsburgh Lisa Storrie-Lombardi, Caltech Monica Tosi, OAB Donald G. York, U. Chicago

ST-ECF Newsletter

T

he Space Telescope - European Coordinating Facility publishes a newsletter which, although aimed principally at European Space Telescope users, contains articles of general interest to the HST community. If you wish to be included in the mailing list, please contact the editor and state your affiliation and specific involvement in the Space Te lescope Project. Richard Hook (Editor) Space Telescope European Coordinating Facility Karl Schwarzschild Str. 2 D-85748 Garching bei MÝnchen Germany E-Mail: rhook@eso.org

The Space Telescope Science Institute Newsletter is edited by Robert Brown, rbrown@stsci.edu, who invites comments and suggestions. Technical Lead: Christian Lallo, clallo@stsci.edu Contents Manager: Sharon Toolan, toolan@stsci.edu Design: Krista Wildt, wildt@stsci.edu To record a change of address or to request receipt of the Newsletter, please send a message to address-change@stsci.edu.



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Contents:
Cycle 13 Cycle Cycle Cycle Cycle 13: 13: 13: 13: Peer Review . . . . . . . . . . . . . . TAC and Panel Members . . . . Statistics . . . . . . . . . . . . . . . . Approved Observing Programs Institute News Director 's Perspective . . . . . . . . . . . . . Status of the Hubble `Two-Gyro' Mode Scheduling with Two-Gyro Pointing . . . ACS News . . . . . . . . . . . . . . . . . . . . . . MultiDrizzle . . . . . . . . . . . . . . . . . . . . . UDF News . . . . . . . . . . . . . . . . . . . . . . JWST News . . . . . . . . . . . . . . . . . . . . . MAST News at STScI . . . . . . . . . . . . . Hubble Fellowship Program . . . . . . . . . Hubble Meets the Giant Screen . . . . . . HubbleSite Nomination . . . . . . . . . . . . Hubble's Impact in the Classroom . . . . May Symposium . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 .14 .15 .17 .21 .23 .24 .25 .27 .28 .29 .29 .30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 .5 .6 .8 Cycle 13

Calendar
"Massive Galaxies over Cosmic Time" workshop at STScI . .27­29 September, JWST Science Working Group meeting in Ottobrunn, Germany . .5­6 October, "Two-Gyro Pointing" workshop at STScI . . . . . . . . . . . . . . . . . . . .17 November Space Telescope Users Committee meeting at STScI . . . . . .18­19 November Space Telescope Institute Council meeting at STScI . . . . . . .22­23 November 2004 2004 2004 2004 2004

Contact STScI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 Calendar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32

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