The sky background can contribute significant Poisson noise in broad and medium band filters, and must be taken into account during noise calculations. The actual sky brightness depends on the heliocentric ecliptic coordinates (latitude and longitude) in a manner summarized in Table 6.3 . ... 22.4 . ... An average sky brightness of V=22.9 mag arcsec -2 is assumed. ... Values for other filters or sky brightnesses can be computed from Table 6.2 , Table 6.1 , Table 6.3 , and Equation 6.2. ...

Next: AXAF Recipes Up: ROSAT HRI Recipes Previous: Quantum Efficiency Correction (a.k.a. For some observations, a significant amount of data may have been rejected during SASS processing because the background level was higher than the calculated threshold for rejection. ... REJECTED EVENTS . ... The recipe will allow the user to include rejected events in the generation of a new qpoe file and filter on the background level. ... This creates a qpoe file with standard + rejected events. ...

... 11 Yellow-Green (78% transmission): Contrasts well with the red and blue characteristics of surface features on Jupiter and Saturn. ... 82A Light Blue (73% transmission): Useful on the Moon, Mars, Jupiter, and Saturn, this subtle pale blue filter enhances areas of low contrast while avoiding significant reduction of overall image brightness. ... Meade Series 4000 Photo-Visual Color Filters may be ordered individually or in the following sets: . ... Meade Series 4000 Broadband Nebular Filters . ...

... The J, H and K bands are characterized by a bright background, such a background is mainly due to the emission of atmospheric lines and of thermal radiation. ... If the source cover a large fraction of the slit, spectra off-source must be observed to adequately sample the sky background. ... The on chip integration time (time spent in each position of the slit) must not exceed 40 seconds in J and H bands and 60 seconds in K band. ... We suggest a sequence of 10 for each elementary integration time. ...

... The R , I photometric observations of SBS 0335-052W were obtained occasionally during the study of SBS 0335-052 with the 3.5m telescope in Calar Alto on 1991 October 6. ... Aperture photometry was performed on the standard star observations using MAGNITUDE/CIRCLE task with the same aperture for all stars. ... For photometry of extended objects, we used the package SURFPHOT as well as dedicated software for adaptive filtering developed at the Astrophysical Institute of Potsdam (Lorenz et al. ...

... ATNF Home . About ATNF . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . Australia Telescope Compact Array . Mopra radio telescope . ... Australia Telescope Online Archive (ATOA) . ... Parkes | ... Australia Telescope 20GHz Survey . ... Visiting Parkes radio telescope . Visiting Australia Telescope Compact Array . ... Parkes radio telescope webcam . ...

... The Galactic low-mass X-ray binary GS 2023+338 was discovered during the burst on May 22, 1989 with the Japanise satellite Ginga (aka Galaxy). The flux reached 17 crabs (this unit of flux measurement is an bright X-ray source, Crab Nebula) at 10-35 keV. ... No other radio telescope worldwide carried out multi-frequency measurements. ... Upon 14 days the radio flux fell below the detection level at the RATAN-600 in relation to the decrease of the X-ray flux. ...

adapted from Observe: Eclipses, published in 1979 by the Astronomical League and "Safe Solar Filters," by B. Ralph Chou, Sky and Telescope, August 1981) . ... Tape TWO pieces of film together into a sandwich, and tape this over the opening in the cardboard. ... The cardboard frame will act as a shade from the bright Sun, while you safely observe through the film sandwich. ... Undeveloped film is not safe. ... tape . ... At the end of one of the tubes, tape the aluminum foil, and make a tiny pinhole. ...

... The following charts/text are intended as tools for monitoring the Type Ia supernovae ( SNe ) event visually or photographically (utilizing telescope equipped CCD equipment).The files include: A replication of The Type Ia SNe , V- magnitude (with data point checks from other cited references)and color index (B-V) templete (to indicate a general color-related trend of the type Ia ... I believe this might help alleviate some of the problems involving the making of acceptable amateur light curves...

... Tonight's Sky . ... Observing . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... solar system . galaxies . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Astronomy for Kids . ... Imaging Basics . ... Observing Basics . ... Observing Basics: Visual Solar Filters . ... Expand your observing at Astronomy.com . ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ...

... A1 centered at 2500 angstroms with a width of 1200 angstroms . ... UGC 6151 is a Low Surface Brightness Galaxy which is at the center of the first deep survey field taken with UIT. The total exposure time was 1370 seconds out of a planned 2000 through the A1 filter. ... The galaxy has very faint outer spiral structure and tightly wound inner spiral structure. The outer spiral structure should be more prominent at UV wavelengths if star formation is occurring out there. ...

... Up: Proposal Processing . ... ESO is prototyping a distributed ``Phase II'' system that will allow astronomers to prepare their observations at their home institutions, while maintaining a central repository for all observation data. ... ESO is developing a Phase II Proposal Preparation system (P2PP) to collect detailed scientific programme descriptions, in the form of observation blocks (OB). ... ESO's Phase II Proposal Preparation system is an integral part of the VLT Data Flow System (DFS). ...

... Science Users Information > Observing with ESO Telescopes > Phase 2 Preparation > Observing conditions . ... Service Mode Philosophy . ... The following definitions of the observing conditions are common between Phase 1 preparation and Phase 2 preparation, as well as between Service Mode and Visitor Mode observations. ... There are additional Service Mode Policies and Service Mode Guidelines regarding the observing conditions. ... Seeing (Phase 1) and Image quality (Phase2) constraints . ... Moon . ...

... XMM-Newton SOC Home Page Conferences & Meetings . ... Data Analysis SAS News What is SAS? How to use SAS SAS Workshops SAS Version Changes Download and Install SAS Science Simulator (SciSim) . ... EPIC cameras optical loading . ... The PI is invited to cross-check the expected X-ray flux from the target source (and from any other potentially bright source in the target field of view), or to provide the SOC with her/his own estimate, if not originally specified in the proposal. ...

Home . ... Observing . Exposure Time Calculator (ETC) . Survey processing . ... ESO - Public Surveys . near IR surveys . ... Exposure Time Calculator . ... Survey Area Definition Tool . Recommended values for Detector Integration Time (DIT) . ... Detector Properties . ... Filter properties . ... ESO ][ VISTA Home ] ...

Next: NICMOS/HST H-band (F160W) Images Up: NICMOS Science Previous: HST NICMOS Observations of . ... Observations of P . ... The NICMOS team has devised a comprehensive program of observations of the Galactic Center. ... Data in hand give a first look at variability and a detailed look at the search for the tip of the main sequence will be discussed where NICMOS has demonstrated adequate sensitivity and photometric precision to identify likely O8-B1 stars at the Galactic Center. ...

... mar05: filter bank installed but left in wide band mode. 05apr05: 10db amps placed in pixel 2a,2b path in front of the filter bank. 08apr05: 10db amps placed in front of filter bank for all alfa pixels. 12apr05: 6db attenuators placed before 10db amps. 25apr05: 10db amps are now only in the OH filter bath. ... This allowed the search of the data taken by P2030 (100Mhz bandwidth, cfr 1420Mhz, 64usec samples) between 01feb05 and 01may05 for signals of the aerostat radar. ...

In 2007-2008, the planet Uranus will reach one of its annual equinoxes for the first time since 1966. As a consequence, its five major satellites orbiting in the equatorial plane will undergo a season of mutual eclipses and occultations very similar to the one that Jupiter's Galilean satellites undergo every 6 years. ... Some of these events occur when Uranus is at conjunction, or the satellite is transiting or too close to the limb of the planet. ... Complete table of events . ...

... About ATMoB . ... The Observing Committee is starting an Observing Awards Program to promote observing among the membership of the Amateur Telescope Makers of Boston. ... Participant must be a current member of the Amateur Telescope Makers of Boston . ... To qualify for your Observing Award Certificate, turn in your worksheet and drawings to an ATMoB Observing Committee member or observing@atmob.org . ... This Excel sheet has useful macros. ... Copyright (c) Amateur Telescope Makers of Boston, Inc. ...

... ARCSAT ID NUMBER: AS09 DESCRIPTIVE TITLE: Monitoring H-alpha Variability in Be Stars in Young Clusters PI: Steven Souza (Williams College) OBSERVER(S): Steven Souza UNCERTIFIED/UNTRAINED OBSERVERS: summer research students Hallee Wong (Williams College '18), Aylin Garcia Soto (Wesleyan University '18) COLLABORATORS: none CONTACT INFORMATION: Steven Souza; ssouza@williams.edu; 413-441-9892 TIME REQUESTED: My request is for one week total during Q3. ...