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Journal of the Amateur Astrono mers Association of New York January 2011 Volume 59 Number 1, ISSN 0146-7662

EYEPIECE
want to ha ve the incr eased reactivity of arsenate," said biochemist Steven Benner of the Foundation for Applied Molecular Evolution in Gainesville, Fla., during the press confer ence. Results of Wolfe-Simons research appear in the December 2 issue of Science ma gazine. Research has shown that many bacteria can tolerate high levels of arsenic. But Wolfe-Simon found this bacterium can go a step further. When starved of phosphorus, it can incorporate arsenic into its DNA, and continue growing as though nothing remarkable happened. "It can do it in DNA, but it looks like it ca n do it in a whole lot of other biomolecules" as well, Wolfe-Simon says. "Its the first time in the history of biology that ther es been anything found that can use one of the differ ent elements in the basic structure," says Paul Davies, dir ector of BEYOND: Center for Funda mental Concepts in Arsenic Discovery continued on page 13

Arsenic Discovery May Affect Search for Life Elsewhere
By Dan Harrison
In a major discovery that could broaden the search for life beyond Earth, NASA last month announced discover y of an Earth microbe that thrives on arsenic. A bacterium found in a briny California lake doesnt just tolerate arsenic, but can incorporate it into its DNA and other vital molecules in place of the usual phosphorus. "We've cracked open the door to what's possible for life elsewher e in the universe," said study lea d author Felisa Wolfe-Simon, NASA astrobiology research fellow at the U.S. Geological Survey in Menlo Park, Calif., at a December 2 press confer ence. Scientists had regarded phosphorus as one of six key ingr edients--along with carbon, hydr ogen, nitrogen, oxygen and sulfur --that all life on Earth needs to survive. So finding a microbe that substitutes arsenic for phosphorus may funda mentally cha nge the wa y we define life, and perhaps the way we look for it. In particular, scientists hunting for life on Titan, Mars and other bodies throughout the solar system a nd beyond should open their minds, according to researchers. If some life for ms on Earth are doing something so radically differ ent, who knows what alien life might look like? The discover y underscor es that researchers shouldnt focus narrowly on looking for signatures of certain molecules. Rather, they should assess a variety of variables at any particular site. Arsenic may be a more likely life ingredient than phosphorus in certain environments, such as Titan, researchers said. Titan is so cold--temperatures average minus 290 degr ees--that stable molecules like phosphate might not be reactive enough to help generate or sustain life. In the strange bacterium, the much more unstable arsena te apparently ca n take its place. On Titan, "you might well

Robert Little Is Dead at 77
By Dan Harrison
Robert Little, the longtime AAA member who was an expert on astrophotography and wr ote a much-praised book on the subject, died December 8 at his home in Brooklyn. He was 77. Littles expertise in astrophotography and observing was recognized two years ago when he was presented with the clubs rarely awarded Amateur Astronomers Medal. The meda l, which recognizes meritorious ser vice Robert Little continued on page 12


What's Up
By Tony Hoffman The Sky for January 2011
Morning and Evening Planets. Venus has blazed in the predawn sky for a couple of months, and is joined early this month by Mercury. On January 8 and 9, Venus and Mercury reach their greatest elongation from the S un within a day of each other. Venus, near Theta Librae, blazes at magnitude -4.6, while Mercury shines at magnitude -0.3. Mercury continues to brighten, even as it sinks into the twilight, and is visible for most of the month. Saturn is also visible in the mor ning sky, near the star Theta Vir ginis. Its rings continue to open, and are now inclined 10 degr ees to our line of sight. Jupiter continues to dominate the evening sky, even as it recedes from Earth and slowly slips westward. It shines at magnitude -2.3, and its disk spans nearly 40 arc -seconds, large enough to revea l cloud belts in the sma llest telescope and intricate detail in larger scopes. On January 17, observers can see the shadows of both Io a nd Ganymede transit Jupiters disk in the early evening. European Solar Eclipse. Eclipses often come in pairs. Just two weeks after December's total lunar eclipse, there comes a solar eclipse on January 4. Unfortunately, it won't be visible on this side of the world. It can be seen as a partial eclipse in Europe and parts of Africa and Asia, with maximum eclipse in Sweden, the Moon will cover 86% of the Sun. Good Prospects for Quadrantid Meteors. Also coinciding with the New Moon on January 4 is the annual Quadrantid meteor shower. With the Moon out of the way, up to 120 meteors per hour may be visible from dark-sky sites in the pr edawn sky. January 2 Moon lies near Mercury. January 3 Earth is at perihelion, 91.4 million miles from the Sun. January 4 New Moon at 4:03 a.m.; partial solar eclipse (see above); Quadrantid meteor shower pea ks. January 7 Venus is at greatest elongation west of the Sun (47 degr ees). January 9 Mercury is at greatest elongation west of the
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Sun (23 degr ees). January 10 Moon lies near Jupiter. January 12 First-quarter Moon at 6:31 a.m. January 15 Venus lies near Antares. January 19 Full Moon at 4:21 p.m. January 21 Moon is at perigee, 225,428 miles from Earth, 7:09 p.m. January 25 Moon lies near Saturn. January 26 Last-quarter Moon at 7:57 a.m.

Saturn and Venus Return To the Morning Sky
By Joseph A. Fedrick
By October 10, Venus was no longer visible from my observing location before sunset, but was visible in the afternoon in my 10x 50 binoculars as a crescent facing slightly upward toward the Sun. It vanished into the Sun toward infer ior conjunction on October 29, then rapidly reappeared in the mor ning sky by November 7 as a large thin crescent just after sunrise. On November 9, it was visible, again as a large thin crescent in the dark presunrise sky in my binoculars and 60mm scope. The planet's disk diminished in size as the cr escent grew thicker during November and December. Saturn reappeared in the earlier during November, degr ees, with the north The South Equatorial Belt bility during December. A last week of October and rose its rings now tilted nearly 10 side visible in my refractor. of Jupiter faded to near invisirevival hadn't yet occurred.

Comet's Pronounced Changes
A newly discovered comet seems to be under going dyna mic changes. Japanese amateur astronomers first detected Ikeya-Murakami in November. Several others have since watched its changing appearance. The comet appears to brightening, so it could be in the middle of an outburst. While it cant be seen naked eye, it should be easily seen with backyard scopes. But finding a comet with a scope can be tricky for those unfa miliar with sky charts and the night sky. Russian observer Leonid Elenin said in follow-up observations, the outer coma had disappeared. "But I saw an excellent inner coComet continued on page 5


A Message from AAA President Richard Rosenberg
Hello members: More than one-third of our members have r enewed a s of the first week of December. If you haven't yet done so, please renew now. Use the enclosed self -addressed envelope recently mailed to you, or mail your check or money order to Amateur Astronomers Association, P.O. Box 150253, Brooklyn, NY 11215. Some highlights to look for in 2011: In the evening sky, Jupiter will be visible from January through March, to be replaced until August by Saturn. Saturn in turn yields to Jupiter in September through years end. Joining these two planets is Mercury, rising up to reach Jupiter in March and again in July. Venus returns to the evening sky in October. The most spectacular gathering of the year is in Mays mor ning sky. Mars, Jupiter, Mercury and Venus cha nge their positions almost ever y da y. The pla nets form close conjunctions and trios. Mars and Venus spend almost the whole year in the mor ning sky. One of the lesser-known benefits available to AAA members is free use of our DVD Library. This includes mor e than 25 disks from Astronomy ma gazines "Infinite Cosmos" series, which grows each month. Topics cover ed include "Constellations," "Apollo 13: To the Edge and Back," "Astrobiology," "Supernovas" and "Dark Matter/Dark Energy." We also have several disks fr om NASA, including "Chandra X-Ray Observator y," "Space Faring: the Radiation Challenge, " and "Field Trip to the Moon: LRO/LCROSS Edition." A complete list of our collection is on our website at www.aaa.org/dvdlibrary. If you see something you like, let me know and Ill get it to you. All disks are free and available for up to 30 days to members. Copies of the Obser vers Handbook 2011 are still available for $18.95. Contact me if you'r e interested. May I take this opportunity to wish you and yours a happy and healthy new year. Rich Rosenberg, president@aaa.org, (718) 522-5014

AAA's January 7 Lecture: Best Astronomy Pictures of 2010
Robert Nemiroff, professor of physics at Michigan Technological University, will show "Best Astronomy Pictures of 2010" at an AAA lecture Friday, January 7. The fr ee public lecture is at 6:15 p. m. at the Kaufma nn Theater of the AMNH. Nemir off will show pictures from the popular Astronomy Picture of the Day website, which he co-founded in 1995. It had an estimated 300 million hits in 2009. Nemir offs research areas include ga mma -ray bursts, gr a vit a t io na l le ns in g, c os mol o g y a nd s ky monitoring. Hes placed video lectures for his classes "Introductory Astronomy" and "Extraordinary Concepts in Physics" on iTunes and the Web for free. Other AAA lectures are: February 4, Neil Weiner, NYU, "Illuminating Dark Matter." March 4, Andrea Dupree, Harvard-S mithsonia n Center for Astrophysics, "Searching for Extrasolar Planets with Kepler." April 1, Greg Matloff, New York City College of Technology, "Regr eening the Earth Using Space Resources." May 6, David J. Thompson, NAS A, "Exploring the Extr eme Universe with the F er mi Gamma-ray Space Telescope. " Duprees talk will be the annual John Marshall Memorial Lecture, honoring a past president and executive director of the AAA.
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Mars May Have Had Life, Phoenix Mission Revealed
By Maya Kushner
NASA's Phoenix mission to Mars deliver ed varied evidence of life markers on Mars during six months of spewing data from the red planet from May to November 2008, the AAA was told December 3. Dr. Suzanne M. M. Young, adjunct professor of chemistry at the University of New Ha mpshir e, who was on the Phoenix tea m, discussed the mission, the first in NASAs Scout Program, under the title "The Phoenix Mission to Mars--The Top 10 Discoveries for NASAs Innovative Explorer of the Red Planet and the Implications for Bio-Habitability." Phoenix was designed to study the history of water and the search for complex or ganic molecules in the Martian arctic. The mission launched in August 2007 and landed in May 2008. It was NASAs first successful landing in a Martian polar region and the first mission to return da ta from either pole. The Martian day (sol) lasts 24 hours and 37 minutes, and the primary mission was expected to last 90 sols, a little over 92 Earth days. The craft exceeded its expected lifetime by two months befor e succumbing to winter. Two main objectives of the mission wer e to study the history of water by exa mining water ice below the surface, and to gauge if arctic soil could support life. As Phoenix landed, the Mars Reconnaissance Orbiters (MRO) HiRISE camera photographed Phoenix suspended from its parachute during its descent. This marked the first time a spacecraft had photographed another in the act of la nding on a planet. Lander ima ges of the la nding site showed "polygonal" cracking (due to expansion and contraction of terrain), plus elevation and trough. Young outlined the mission's top 10 discoveries: On November 10, 2008, Mission Control lost contact. 1. Since Phoenix landed in an area wher e it could test for water, this was accomplished from some sa mples tested by the robotic arm, and confir med water ice.
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2. It found small concentrations of salts that are nutrients for life (sodium, potassium, chloride, bicarbonate, ma gnesium, etc.). 3. The Wet Chemistry Lab unexpectedly uncover ed evidence of perchlorates, a potential source of ener gy for microbes (by anaer obic reduction). The chemical, when mixed with water, can lower freezing points. 4. No obvious evidence of an inhospitable environment, and no poisons, was found. It was deter mined that the Mars regolith is slightly alkaline/basic (pH 7.7 to 8.2). Water is 7, so the pH discover ed is close to that of Earths oceans and isnt extr eme or in any way inhospitable to micr obial life. 5. Calcium carbonates wer e discover ed. These are a marker of effects of liquid water, leading scientists to believe the site had been wet or da mp in the geologic past. 6. A ther mal conductivity probe in the soil detected the evidence for thin films of water in the soil--i. e., "dew." 7. Excavated soil above the ice table revealed at least two distinct ice types. 8. As temperatures dropped in late summer, snow was obser ved descending from clouds, using a meteorological station, and temperature and pressure sensors, among other gauges. 9. Phoenix provided a mission-long weather record with data on temperature, pressure, humidity and wind. Observations of haze, clouds, frost, whirlwinds and the like wer e ma de by the MRO. 10.The microscopy station repeatedly discover ed 3-4 micron-size particles in samples.

Phoenix was consider ed a success because it exceeded its planned length by several months, and made significant contributions toward bio-habitability implications,


The Road to Stardom in the Milky Way
By Evan Schneider
By measuring the composition a nd characteristics of stars across the Milky Way, NASA scientist Paul F. Goldsmith has identified stars as young as 1 million years. Since the Milky Way is mor e than 13 billion years old, this confir ms the galaxys star formation is an ongoing process and ca n continue for billions of years, he told a Hayden audience November 15. Goldsmith, project scientist for the Herschel Space Observator y, spoke on "The Road to Stardom in the Milky Way." He noted that although stars have various proportions and composition, their distances prevent us from physical observation. This leaves us with the one component we ca n observe: light emitted by each star. The speaker began by fa miliarizing the audience with the characteristics of stars, defining light as "electroma gnetic radiation seen at visible and other wavelengths." The "stellar structure," he stated, "is a combination of hydrogen, helium and nuclear reactions." With the Milky Way having more than 200 billion stars, ther e are many opportunities to observe and evalua te them. The color of a star depends upon its temperature, and luminosity can indicate its age. What stars are formed from has long been a major question. Utilizing technology such as radio wa ves, infrared and X-ray, scientists can see stars invisible to the naked eye. With a larger body of stars to observe, determining what stars are ma de of began. Interstellar dust was first thought to be the main component of stars, but identifying the dust as silicon and oxygen in 1919 proved ther e was no hydr ogen. In 1951, atomic hydr ogen was discovered in interstellar space, but this isnt associated with young stars. In 1970, tracers of molecular hydrogen wer e detected. Utilizing this indicator, the study of molecular clouds both dark (no stars for med) and giant (stars formed) advanced. Star formation occurs when gravity forces the clouds to collapse. The runaway effect increases density and gravity. Goldsmith described various conditions wher e planets are for med. Planets for ming in a disk around a protostar begin with planetesimals (clumps of gas and dust). If the accretion is in a cold region far from the star, a Jupiter like planet forms. If accretion occurs close to the star, just dust remains as the gas burns off, leaving planets similar to our solar systems rocky pla nets. More than 500 exoplanets ha ve been found. Telescopes can measure the light drop during transits, and radial velocity. Many different arrays and equipment on Earth and in space measure characteristics of stars, planets and galaxies. The Kepler mission, searching for habitable planets from a space telescope, monitors 100,000 stars, continuously looking for transits. The Cornell Caltech Atacama Telescope is a ground-based telescope observing primeval galaxies on a wide-field submillimeter level. The James Webb Space Telescope will use infrared technology, the best way to study galaxies. Herschel carries the largest mirror ever deployed at 3.5 meters, 930,000 miles from Earth. It observes star for ming clouds and seeks indications of life-for ming molecules such as water. By obser ving all frequencies, it inventories light molecules and pr e-biotic molecules. These observations will yield a survey which will map the Milky Ways inner galactic plane in five bands. AAA me mber Maya Kushner asked: "Can elements in stars be recycled forever or will the supply of hydrogen and helium be used up at some point in the future?" The reply was bad news for the universe: Although elements can get trapped in black holes or drained off to stellar dead ends (large a mounts of matter get recycled), in the end stars run out of material and no life-sustaining medium rema ins--at least for life as we know it. Comet continued from page 2

coma. We can also see a bright, sufficiently long tail." Gregg Ruppel, fro m Ellisville, Mo., also saw the comet brighten. "The comet rose just before sunrise and was immersed in light pollution and haze. But when I positioned my astrograph to the expected location, there it was. At first I wasnt sure if it was a tail because I tracked the comet and the stars appear trailed. But it brightened 5 considerably over a few da ys."


Taking a Digital Grand Tour of the Universe
By Edward J. Fox
There have been two presentations on the Digital Universe Atlas at the Hayden Pla netarium in the past two months. The first was on the 10th anniversary of the atlas, which concentrated on its histor y and mechanics. It included a description of various data that have been a nd continue to be a dded to the most compr ehensive r esource of its kind. The second production, November 26, was the Grand Tour of the Universe by Bryan Abbott, ma nager of the atlas, and Ted Willia ms, a visiting lecturer from Philadelphias Rittenhouse Astronomical Society. According to Abbott, "This is the entir e universe in one sitting." Highlights of the trip follow. The tour began with a demonstration of the 100 brightest satellites circling the Earth. More of the almost 3,000 satellites circling the Earth wer e "turned on" to demonstrate not only their sheer number, but also how close to Earth they really are. Ther e are thousands more man ma de objects in orbit. These are tracked by the United States Space Surveillance Network (SSN). Because this was a tour of the universe a nd not the solar system, the latter was quickly exited. On the way out, the paths of the two Voyager space probes wer e shown, including how they wer e "slingshotted" around the solar system to r each the outer planets. Their present positions wer e shown, as well as projected paths and positions in 50 years. Next was location of the known exoplanets. The inclusion of the recently discover ed HR 8799 e was an example of the datas timeliness. The National Research Councils Herzber g Institute of Astrophysicists discover ed the planet November 1 while taking a closer look at the HR 8799 system and published its findings three weeks later, just days before this presentation. HR 9799 e is a large exoplanet, orbiting HR 8799, 128 light-years from Earth. The pla net is 5-13 times the ma ss of Jupiter. The speakers said exoplanets are being discover ed so frequently, their existence is no longer announced individually. Rather, they are periodically an6

nounced in groups. The Milky Way followed. Its dust and gases wer e described, as wer e its size and spiral for mation. Obviously, we ca nnot see the entir e galaxy, since we are within it, so the ima ge of another spiral galaxy is used as a proxy. Our closest neighboring galaxies of the Magellanic clouds wer e described next. Since the irregular systems are much smaller and less massive than the Milky Way, the clouds provide us with environments to see how their ma keup and surroundings can change the life cycles of stars. Abbott and Willia ms described various types of galaxies--spiral and globular--quasars and other objects. We wer e carried back in space-time to the theor etical edge of the cosmic ray background (CRB), befor e which the universe would have been a thick impenetrable fog. Although much of what had been shown a month earlier was the same, plans call for this Grand Tour of the Universe to be r epeated about twice a year. Surely, at that time ther e will have been a number of new discoveries, which, due to timely a nd compr ehensive a ddition of data to the Digital Atlas, will be presented. An abbreviated program of the Grand Tour of the Universe can be vi e w ed a t ht t p :/ / www. y ou t u b e. c om/ wa t c h? v=HRq1YuFEfW4. The basic Digital Universe Atlas is distributed via packages that contain the Milky Way Atlas and the Extragalactic Atlas. Free software (Partiview, precursor to Uniview) allows one to explor e the universe by flying t h r o u g h i t o n y o u r c o mp u t e r . S e e h t t p : / / www. haydenplanetarium.org/universe/download/.

Contacting the AAA
General club matters: president@aaa.org. Membership business, such as dues and change of addr ess: members@aaa.org. Eyepiece: editor@aaa.org. Lectures: lectures@aaa.org. Classes: classes@aaa.org. Seminar: seminar@aaa.org. Observing: president@aaa.org. Please visit us on the web at www.aaa.org.


Sizing Up the Universe According to Gott
By Evan Schneider
We live in an amazing universe. Most of us at the AAA have been exposed to the latest data from earthbound telescopes, orbiting telescopes and the ma ny space missions currently in progress. But what if you took all those data and boiled them down into one book and one lecture at the AMNH? What you would get is a unique collaboration between J. Richard Gott, professor of astrophysics at Princeton, and his amateur astronomer and technically proficient astrophotographer colleague Robert J. Vanderbei, professor and chair of the Department of Operations Research and Fina ncial Engineer ing at Princeton. Together, theyve ha ve assembled photographs of our solar system and the universe, and put them into perspective for us to see and understand both in Gotts lecture December 6 at the Hayden and in a magnificent book, "Sizing Up The Universe" (National Geographic, $35). With Hayden dir ector Neil deGrasse Tysons introduction both in person and on the jacket cover, we bega n our journey. The concepts of apparent size and angular size yield a significant a mount of infor mation. As an exa mple, our Moon and Sun occupy the same angular size in the sky, one half of a degree. But the Sun is 400 times farther away than the Moon, so the Sun is 400 times wider than the Moon. By comparing a close object to a faraway object, we ca n deter mine its size relative to the close object. Gott makes many of these comparisons to underscor e his point that we can measur e the size of distant galaxies and stars through the use of observation and comparative analyses. Ther e are objects with a greater apparent size than the Moon, yet theyre not visible to us because their faint light emissions preclude our eyes from seeing them. The Rosette Nebula in our own galaxy is twice the apparent size of the Moon in the sky. The Andr omeda galaxy, 2.2 million light-years away, is five times the apparent size of the Moon. Yet faint light from the gas regions of Rosette makes it appear smaller and Andromeda s gr eat distance makes its light fainter and it, too, appears sma ller. What about the scale of the universe? How far is far? To answer these questions, Gott took us on a journey unlike any Ive seen. We were presented with the Gott Juric Map of the Universe, "a map representing a 360 degr ee panorama looking out from Earths equator." The surface of the Earth is at the bottom of the map, and as we move up the map, we travel farther into the universe, past the Oort cloud to our first stop, 100 billion Earth radii away, the current limit of radio signals from Earth. Then we push farther out, to the end of the Milky Way, 100 trillion Earth radii away. After that, its across the universe to the Great Sloan Wall, which we have seen in The Digital Universe presentations at the Hayden, more than one quintillion Earth radii away. Our journey ends at the cosmic microwave backgr ound (CMB), the farthest ima ge ever recorded, 13.7 billion light-years away. Now that we know how far the CMB is and whats on the way to it, lets pull in and get a feel for the immedia te scale of our solar system. For instance, we can fit 1 million Earths into the Sun. The entir e United States would fit into a single sunspot. Our Grand Canyon, the largest on Earth, is 117 miles long, but the Va lles Marineris on Mars stretches 2,485 miles. Ther e are similarities in our differ ences as well. There are lakes of water on Earth, lakes of methane on Titan, volca noes on Earth and volcanoes on Jupiters moon Io. These similarities must exist in other solar systems thr oughout the universe. Whats beyond the visible universe? Gott has his own theory of "bubble universes." Were just one bubble of an inflating universe, wher e, like a tree, other universes can expand off a primary branch. This leads to an infinite number of universes expanding at nearly the speed of light. Unfortunately, well never see these other branches since theyre expa nding much faster than light can cross them. Physicists are exploring ma ny models for universes expansion. Gotts model is just one exa mple of this initiative, but all of these brilliant speculations still lea ve us with one ma jor question that may never be answer ed: How did the universe begin? Many believe the solution lies in the Big Bang, but for the answer, only time will tell.

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Review: SETI Heads into its Second Half-Century
By Anne Kiefer
Like so many others who have spent time watching "E.T." and reruns of "Doctor Who," I have found my ima gination always drifting to the day humans meet the little green men with ray guns and the ability to teleport. The success of the myr iad of Hollywood movies, books and TV shows about alien encounters goes to show that nearly ever ybody wonders if something else is out there. Last year, SETI, the Search for Extra-Terrestrial Intelligence, celebrated its 50th anniversary of researching that very topic. Of course, SETI has a more scientific approach tha n the writers of "Independence Da y," but the question is the same: Ar e we alone? In "The Eerie Silence" (Houghton Mifflin Harcourt, $27), Paul Davies discusses the history of SETI, an organization to which hes dedicated most of his career, and takes a critical look at its goals, assumptions and practices. He acknowledges that after 50 years of running a project the sa me way, SETI needs new ideas. Davies has written a comprehensive and technical book while rema ining accessible to the less scienceminded a mong us. He capably explains the competing schools of thought about extra-terrestrial intelligence in detail without getting bogged down by the complexity of the issue. Even at its most technical moments, the book remains engaging. I approached this book with a skeptical eye, and I often found myself questioning SETIs theories and practices. It seemed at times that its entire research paradigm is made up of assumptions built on assumptions --a precarious house of cards. When I first started the book, I constantly questioned SETIs assumptions about the beings they were searching for. For example, SETI uses radio waves to communicate. This is in part because it began in the ,,60s, but over time it still used that somewhat dated technology. Ther e are a few valid reasons to choose radio as a method of contact, but Davies agrees its a problem in the central dogma of SETI. "Eavesdropping on an extraterrestrial civilization on the pr emise that the aliens may still be using 1980s human technology is a hard sell."
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Another issue I had with many of SETIs approaches was the tendency to fall back on anthropomorphism. Since were discussing something completely differ ent from us, its nearly impossible to completely avoid ima gining that extraterrestrial civilizations are similar to us. The fact is, however, that we simply dont know if any other civilizations are using the sa me technology, need the sa me things to survive or even have the sa me drive to find other civilizations. Their way of thinking ma y be so for eign to us that any sort of comparison is futile. However, if SETIs goal is to communicate with an extraterrestrial civilization and form any sort of relationship, we have to assume its somewhat like us and able to do so. Davies addr esses this issue ma ny times, both as a criticism of SETI and almost as a disclaimer about his own writing. He admits that as his narrative moves forward he is moving farther from "real" science a nd more into the r ealm of science fiction, and as he does so, he often falls back on anthropomorphic crutches. I was impressed that, even as an insider, Davies addr essed most of my concer ns as the book progr essed. He has used the book as an opportunity to take SETI apart, brick by brick, and analyze the entir e approach. It takes a special degree of optimism a nd dedication to still believe in SETI after 50 difficult years of research without a major victory, and Davies uses this book to celebrate the work of SETI researchers. He reminds us that retaining a robust skepticism need not prevent us from approaching SETI in a methodical and penetrating way, infor med by the ver y best science we have."

Global Effort--The International Year of Astronomy 2009 was a huge success, involving 148 countries, and hundreds of thousands of activities reaching hundr eds of millions. As part of IYAs legacy, the International Astronomical Union is implementing a decadelong plan for the global development of astronomy, The Strategic Plan: Astronomy for the Developing World. Starting in March, the Office for Astronomy Development will coordinate a range of activities designed to promote astronomy throughout the developing world.


Briefs: Alien Planet Is Discovered in the Milky Way
Astronomers have confirmed the first discover y of an alien planet in the Milky Way that came from another galaxy. The Jupiter-like planet orbits a star that was captured by the Milky Way 6 billion-9 billion years ago. Astronomers cant observe stars in for eign galaxies for planets and confir m them since these stars are too far away. This is the first planet discovered to be circling a star thats both very old and extremely metal-poor. The planet, HIP 13044b, survived through its stars red-giant phase, so it could offer clues about our solar systems fate. HIP 13044b completes an orbit ever y 16.2 days and comes within 5 million miles of its star at closest approach. The planets 25% mor e massive than Jupiter and orbits its star about 2,000 light-years from Earth in Fornax. The star, nearing the end of its life, is less than 1% as metal-rich as our Sun, so its the most metal-poor star known to host a planet. Because the star is metal-poor, its planet may have for med via the gravitational attraction between gas molecules, so it ma y not have a rocky cor e. HIP 13044b likely once orbited much farther away from its star but spiraled closer during red-giant phase due to friction with the swollen stars envelope. A comet visited by NASA's Deep Impact probe in November is spewing jets of vaporized dry ice into space. Previously it was thought vapor from water ice was the force behind jets coming off the nucleus of Comet Hartley 2. Deep Impact flew within 435 miles of Hartley 2 and bea med close-up photos. Ima ges show spectacular jets of gas and particles bursting from ma ny spots on the surface. The flyby provided the clearest views of any comet, and allowed r esearchers to link jets of dust and gas with surface features. The jets are primarily carbon dioxide gas, and particles of dust and ice. Flyby photos and data showed buried but frozen carbon dioxide on Hartley 2 turns into gas when heated by sunlight. Water and carbon dioxide dominate the infrared spectrum of the comets environment. Organic material is present at lower levels. Carbon dioxide, rather than water, takes dust grains into the coma as it lea ves the nucleus. Dry ice producing carbon dioxide jets on the comet has probably been frozen inside it since for mation of the solar system. A massive storm, erupting from the Sun last month, created a long fila ment of ma gnetic plasma extending 435,000 miles across the Suns southeastern r egion. The structure was an easy target for backyard telescopes and had the potential for an impr essive eruption. Amateur astronomers acted fast since the fila ment was temporary. "The...structure...hover ed quietly above the stellar surface, but [showed] signs of instability," Spaceweather.com reported. "Long fila ments like this have collapsed with explosive results when they hit the stellar surface below." The fila ment followed a similar Sun eruption in November. That filament stretched across 372,800 miles. The blast was from an active group of sunspots called 1121, the thir d major flare from the hotspot. At the time of the flare, 1121 was on the limb, or edge, of the Suns disk, so any cloud of electrified particles ejected wouldnt reach Earth. But as the Sun rotates, this region will be turned toward the center of its disk. Radiation from the flare "created a wave of ionization in Earths upper atmospher e that alter ed the propagation of low-fr equency radio wa ves," said Spaceweather.com. NASA has developed an early warning system to fight massive solar eruptions and protect electrical grids. Solar Shield aims to predict severity of stor ms at specific locations. The chief target is coronal mass ejections (CMEs). The project provides short- and long-ter m predictions of impending CMEs. Once a CME is registered, a 3-D model provides a prediction on arrival time, from 24to 48 hours. While the CME travels through space, computers create generalized predictions. As the CME moves closer, it passes a space-weather satellite 30-60 minutes befor e reaching us. This refines predictions. The dwarf planet Eris--once thought to be the largest body in the solar system beyond Neptune--ma y be sma ller than Pluto, new observations suggest. As Eris passed in front of a distant star in Cetus, the length of the occultation showed Eris is likely less than1, 454 miles wide, vs. about 1,455 miles wide for Pluto. Astronomers still believe Eris is 25% more massive than Pluto. The size revision would allow Pluto to again be the largest body in the Kuiper Belt. Eris probably contains more rock and less ice than Pluto. A cosmic explosion seen 31 years ago ma y have indicated the youngest black hole ever obser ved, which could help researchers understand how black holes are Continued on page 10
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Briefs: Webb Cost Overruns May Hit Other NASA Missions
Continued from page 10 born and evolve. Studying baby black holes should also help astronomers know what deter mines the fate of stars, as well as how common black holes are in our gala xy and the universe. This is the first time the exact birth da te of a black hole has been known. Chandra picked up strong X-ray emissions from the region around a supernova, SN 1979C, about 50 million light-years away in M100, which was observed exploding in 1979. Other instruments also noticed the bright source of X-rays, which rema ined steady from 1995 to 2007. The X-ray emissions are consistent with radiation thrown off by a black hole gobbling up gas and dust. The object appears to be about five times as massive as our Sun. This black hole is much closer than others. It also doesnt seem to have a gamma-ray burst. Researchers think the star that exploded to for m SN 1979C was 20 times as massive as our Sun. Stars less than 20 solar masses tend to for m neutron stars, while larger ones turn into black holes. A galaxy thought to be over the hill is apparently still creating baby stars, a new study finds. Hubble photos show the core of an elliptical galaxy, NGC 4150, awash in streamers of dust, gas and clumps of young, blue stars significa ntly less than 1 billion years old. Observations suggest elliptical galaxies still have youthful vigor, thanks to encounters with smaller galaxies. Evidence also suggests star birth in NGC 4150 was sparked by a collision and mer ger with a dwarf galaxy. A tea m calculated star formations started about 1 billion years ago but has slowed since. The youngest stars are 50 million300million/400 million years old. Most stars in the galaxy are around 10 billion years old. Massive cost overruns on NASAs James Webb Space Telescope (JWST) will imperil funding for the agencys orbital astronomy missions while potentially wiping out big-ticket space observatories and a host of less-expensive development projects deemed high priorities by the science community, experts believe. S ome believe cost growth could ravage the agencys $1.1 billion annual astrophysics budget, 40% of which is already consumed by the JWST. Even at best case, the $1.5 billion cost surge may virtually wipe out visions of the decadal survey in astrophysics for 2010-20. The recent National Research Council (NRC) report laid out the sci10

ence communitys top astrophysics-r esearch priorities for the next decade. It called the $1.6 billion Wide-Field Infrared Survey Telescope the top priority for large missions and recommended NAS A continue spending about $100 million annually on more modestly priced missions. Scientists participating in the survey wer e told to assume NAS As astrophysics budget would r ema in flat or decline slightly during the decade. The panel took into account the strain more JWST delays would impose on the astrophysics budget. NAS A has spent about $3 billion on the JWST. NASAs budget for new astrophysics missions was already stretched before new JWST cost estimates wer e released. The NRC report says it will cost $1.9 billion in the next five years to finish building and launch the observatory, some 300% mor e than pla nned. Astronomers have discovered a dozen previously unknown double-star systems, each on course to end in spectacular explosions detonated by the crash between their two small, dense stars. All systems consist of two white dwarfs. Of the 12, about half will likely see their stars merge into one, then explode. The tightest binary system, in which its stars circle each other ever y hour, will mer ge in about 100 million years. White dwarfs in the survey hold only about 20% the mass as the Sun. Theyr e made almost entirely of helium, unlike nor mal white dwarfs made of carbon and oxygen. When white dwarfs merge, their combined mass can exceed a tipping point, causing them to explode as Type Ia supernovae. Saturn is a changeable world that pumps out surprisingly variable amounts of heat from season to season and year to year, a new study reports. Saturn emitted less ener gy from 2005 to 2009, according to Cassini observations. Its ener gy output also changed with the planets seasons, and its pattern differ ed from the early 1980s, the last time a spacecraft visited Saturn. Scientists had thought planets tend to emit energy at a steady rate. That Saturn emits mor e than twice the energy it absorbs from the Sun has long been a puzzle. Scientists tend to think of pla nets losing power evenly in all dir ections and at a steady rate. Saturns southern hemispher e gave off about one-sixth mor e energy than the northern half from 2005 to 2009.That matched up with Saturns seasons. Over those five years, it was summer in the souther n hemiContinued on page 11


Briefs: Japanese Spaceraft Returns Asteroid Samples
Continued from page 10 spher e and winter in the norther n hemispher e. Cassini found Saturn as a whole was slowly cooling over the period, emitting gradually less ener gy every year. Changes in Saturns emitted power ma y be related to cloud cover. But to understand whats happening, scientists must know the a mount of power its absorbing. A Japanese spacecraft that touched down on an asteroid during a 1.25 billion-mile mission returned the first samples from the surface of an asteroid: tiny dust grains collected fr om Itokawa in 2005 by the Ha yabusa spacecraft, which returned in June. About 1,500 grains were identified as rocky particles. Most wer e judged to be from Itoka wa. Scientists knew ther e wer e particles of material in the sample-return capsule, but were unsur e if they wer e pieces of an asteroid, cosmic dust or contamination from Earth. Itokawa is a silicon-rich rock 1,755 feet long at its longest side. Astronomers seeking Earth-like alien worlds could improve their odds by zer oing in on planets that look blue from afar, just like Earth, a new study suggests. Larger telescopes will ha ve light-gather ing power to look at planet colors, gauging which to study in mor e detail. Scientists used new color info about Earth, the Moon and Mars gather ed by NASAs Deep Impact as it headed towards Comet Hartley 2 in November. The tea m added to these observations with color info about Mercury, Venus, Jupiter, Saturn, Uranus, Neptune and Titan. Color data from three filters--green light, red and blue-- separated the pla nets from each other. Earth didnt cluster with other planets. Its uniqueness is due to scattering of blue light by its atmospher e and that it doesnt absorb much infrared. If an alien planet shows a similar color fingerprint to Earths, it wouldnt necessarily mean it has blue skies and vast oceans. A huge snakelike tendril of ma gnetic plasma has appeared on the Sun, extending hundr eds of thousands of miles. The fila ment is 372,800 miles long. Fila ments are long threads of plasma that rise into the corona. Theyre much cooler than the corona and appear to be dark with the Suns disk in the background. They can for m dazzling prominences when viewed along the Suns limb. The new fila ment winds around the southwestern limb and could ultimately erupt into a solar storm or slip back into the surface. Two new studies suggest that when ga mma-ray bursts explode, some ca n lea ve behind black holes, while others ma y end up as spinning neutron stars. Neutron stars are restricted in how massive they can be. If they weigh mor e than a certain limit, gravity would collapse the object into a black hole. Black holes, on the other hand, have no upper-mass limit, so ca n encompass any ma ss needed to power a gamma-ray burst. Scientists said findings dont conflict with each other. The dark brown stripe of clouds on Jupiter that disappeared from view in 2009 is reappearing. Astronomers confir m that Jupiters South Equatorial Belt (SEB), one of two dark stripes for med by cloud chemistry and winds, is coming back. They attributed the r eturn to a shift in Jupiters cloud cover. Amateur astronomer Christopher Go of the P hilippines spotted the beginning of the horizontal stripes revival November 9, when it appeared as a white blotch. It should take 4-6 months to return entirely. The dark band had been temporarily obscured by a white cloud deck ma de of a mmonia ice. Every few decades the SEB appears to disappear, its location turning completely white for 1-3 years. Go was the first to discover that revival as well. "This is mor e spectacular than the revival of 2007," said Go, who also spotted the cloud belts last revival. "In 2007, the SEB didnt completely fade and the revival started prematur ely." Saturn's second-largest moon Rhea has a wispy atmospher e with lots of oxygen and carbon dioxide, a new study has found. Cassini detected Rheas atmosphere during a close flyby in March. The discover y marks the first time an oxygen-rich atmospher e has been found on a Saturn satellite. The news suggests many other large, ice-cover ed bodies throughout the solar system a nd beyond may harbor thin shells of oxygen-rich air and perhaps complex chemistry. Rhea is composed mostly of water ice and, with a dia meter of 950 miles, should have enough gravity to hold onto an atmospher e. Last March, Cassini ca me within 60 miles of Rheas north pole. Oxygen ma kes up 70% of Rheas atmospher e and carbon Continued on page 12
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Briefs: Newfound Galaxy May Show How Structures Form
Continued from page 11 dioxide the rest. Wher e Cassini sa mpled, the atmosphere is 100 times thinner than air cocooning Europa and Ganymede. The study confir ms an ice-derived, oxygenrich atmospher e for the first time outside the Jupiter system. Researchers are pretty sure they know wher e Rheas oxygen comes from: charged particles from Saturns ma gnetospher e blasting apart molecules of water ice. The source of the carbon dioxide is mor e mysterious. Supermassive black holes at the hearts of galaxies have cosmic jets. So do small stellar black holes. Now a baby star, still for ming, has been found to r ely on the same mechanism to produce its own jets. Astronomers detected the first evidence of magnetic fields mingling with the charged particles streaming at nearly the speed of light from a young stellar object, a protostar known as IRAS 18162-2048, about 5,500 light-years away. This suggests that despite the huge differ ences in scale, supermassive black holes, stellar black holes and young stars rely on ma gnetic fields and shock wa ves to focus and accelerate charged particles to near light-speed. The protostars cosmic jet is 17 light-years long. Although constrained budgets ma y spur federal agencies to establish collaborative space missions, theyr e inher ently mor e complex and result in higher costs than independent projects, says a new National Research Council report. So the report recommends that agencies avoid collaborative Earth-obser ving or spacescience missions. If theres a compelling reason to collaborate despite that warning, officials should clearly define the projects scope as well as responsibilities of each tea m member, the report says. Even when ther es a compelling r eason for agencies to work together, the report recommends ways to structure that cooperation without sharing overall responsibility for the project. While inter national cooperative ventur es are more costly than independent programs, those projects can save money for the U.S. because inter national partners absorb some of the missions expense, the report said. A newly discovered galaxy ma y help revea l how the most massive structures in the universe for m and evolve. The boomera ng-shaped galaxy was found in a tendril of
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super-heated gas connecting two massive ga laxy clusters. These tendrils, or fila ments, pervade the universe. Though immense, theyr e tough to see and study in detail. In the new study, gas from a known fila ment was sweeping the previously unknown galaxy into its bent shape. This suggests similarly bent galaxies could serve as signposts for cosmic gas fila ments, which signify fertile star-forming regions. The fila ment runs between galaxy clusters Abell 1763 and Abell 1770. The new gala xy sits inside that fila ment, about 11 million light -years from the center of Abell 1763. The galaxy has an unusual ratio of radio to infrared light, which ma kes it stand out. This is due in part to its twin jets of material, which spew in opposite directions from a super massive black hole at the galaxys center. These jets emit ma ny radio waves. The lobes appear to be bent back and away from the galaxys path through the fila ment. The bow shape is likely caused by particles in the fila ment pushing on gas and dust in the galaxys jet lobes. Density in Robert Little continued from page 1 by amateurs to the science of astronomy, has been a wa r ded o nl y s e v en t i mes s inc e 1 9 7 7 . In 1986, Little's book "Astrophotography: A Step-byStep Approach" was published to wide acclaim. Said one reviewer : "Written by an experienced and sensitive practitioner of his subject, Little's book is packed with information and as complete as its brevity allows....Even the professional astronomer with exper ience in taking photographs on large research telescopes will appreciate many of Littles hints." Even though the book is, to a large degr ee, dated because it was published 24 years ago, its still used by people seeking grounding in astrophotography, including setting up telescopes and tracking techniques. In addition to leading obser ving sessions, including starting those at Cadman Plaza in Brooklyn, Little taught courses on astrophotography at the Hayden Planetarium and on telescopes for the AAA. Recalls AAA pr esident Richard Rosenber g: "My first contact with the AAA was at Cadman Plaza, Robert Little continued on page 14


Events on the Horizon January 2011
M: me mbers; P: open to the public; T: bring your telescopes, binoculars, etc.; C: cancelled if cloudy; HQ: at AAA headquarters, Downtown Community Center, 120 Warren St. AMNH: For ticket information, call (212) 769-5200 For directions to AAA observing events, check the club's website, www.aaa.org. Friday, January 7, 6:15 p. m. AAA lecture, FREE, P Robert Nemiroff of Michigan Technica l University will present the AAA's annual lecture on best astronomy pictures from the previous year, drawn from the popular website Astronomy Picture of the Day. Nemir off cofounded the website with Jerry Bonnell. Monday, January 10, 7:30 p. m. Hayden Planetarium lecture, P, AMNH In "How I Killed Pluto, " astronomer Mike Br own will discuss a tumultuous year in astronomy, which he inadvertently caused. In 2005, Brown discover ed the "10th planet," Eris, which is 27% more massive than Pluto. But Arsenic Discovery continued from page 1 Science at Arizona State University. Wolfe-Simon's finding "can only r einforce people's belief that life can exist under a much wider range of environments than hitherto believed," Micha el New, NASAs astrobiology discipline scientist, agrees: "Discover y of an orga nism that can use arsenic to build its cellular components may indicate that life can for m in the absence of large amounts of available phosphorous, thus increasing the probability of finding life elsewher e." Dimitar Sasselov, an astronomer at the HarvardSmithsonian Center for Astrophysics, said, "Nature only uses a restrictive set of molecules and chemica l reactions out of many thousands available. This is our first glimmer that maybe ther e are other options." Experiments on space missions are designed to ferret out the handful of chemical elements and reactions that have been known to characterize life on Earth. The Viking landers that failed to find life on Mars in 1976, Wolfe-Simon pointed out, wer e designed before the discovery of tube wor ms and other strange life in undersea vents and the dry valleys of Antarctica revolutionized ideas about the evolution of life on Earth. While natures been able to engineer substitutes for some elements that exist in trace amounts for specialized purposes, until now ther es been no substitute for the basic six elements. But now, scientists say, the new r esults will stimulate much work on what other chemical replacements might be possible. Arsenic sits right beneath phosphorus in the periodic table and shares ma ny of its chemical properties. Indeed, that closeness ma kes it toxic, Wolfe-Simon said, allowing it to slip easily into a cells machinery and gu m things up. The cells grown in the arsenic ca me out about 60% larger than cells grown with phosphorus, but with large, empty inter nal spaces. By labeling the arsenic with radioactivity, researchers could conclude that arsenic atoms had taken up position in the micr obes DNA as well as in other molecules within it.
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instead of adding a planet to the solar system, the discover y ignited controversy that culminated with the demotion of Pluto. Brown will discuss his memoir from that year, "How I Killed Pluto and Why It Had It Coming." Thursday, January 13, 6:30-8:30 p. m., 726 BroadWay, sixth floor conference room Recent Advances in Astronomy Seminar, M The seminar now incorporates the Observers' Group. Next date: February 10. Saturday, January 29, 10 a. m.-noon Solar Observing at Central Park, P, T, C At the Conservator y Waters. Next date: F ebruary 26.


Robert Little continued from page 12 when Bob was chair there. I learned him about observing, and thanks to telescopes I chose a scope I use to through Bobs observing sessions that of discover ing the club." a great deal from his knowledge of this day. It was I had the pleasure

was also an eclipse cruise off western Africa, "A Voyage into Darkness." Little lectured on astrophotography and was always getting stopped in the hallways and asked questions about how to set up cameras for the eclipse. His photograph of a total solar eclipse, taken in conjunction with another photographer, appeared on the cover of Life ma gazine. For mer AAA president Lynn Darsh had the picture before she met Little and was very impr essed with his willingness to share his expertise. Former AAA president Micha el OGara said: "Bob offer ed to teach the art of taking pictures of the night sky to our membership and was always available to answer any question regarding photography equipment and telescopes. When an online group approached me to do a weekly show about astronomy a nd observing, Bob was my first guest. The topic was astrophotography, and Bob showed viewers a complete setup of how it's done." Little worked at Scientific American as space salesma n and eastern advertising ma nager, and for Questar, Celestron, and Bausch and Lomb. For Questar, he lectured about astronomy at schools and colleges, and on showing the sky. He was a field scientist and field technical manager for Bausch and Lombs astronomy telescopes. Little is survived by his wife, Ethel.

With the late Fred Hess, Little took cruises to test the proposition that celestial objects could be photographed at sea. Their conclusion it could be done usher ed in the now-widespr ead phenomenon of astronomy cruises. In 1972, Hess put an eclipse-trip organizer in touch with Little. Recalled Little: "The organizer had heard negative comments about whether an eclipse could be photographed from a ship, and called Fred. I was an instructor in astrophotography at the Hayden, and Fred suggested they get in touch with me. Since I had my doubts as well, Fred and I decided to take two pre-cruises to deter mine if it could be done. It turned out to be absolutely easy. Thus bega n whats now a common way to view eclipses." Hess and Little also organized Astronomy Island, a yearly cruise to Ber muda that was held for 15 years. Lectures wer e given aboard ship, as well as star ID talks on deck at night, and talks at a private viewing site. There

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