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Journal of the Amateur Astrono mers Association of New York Nove mber 2010 Volume 58 Number 11, ISSN 0146-7662

EYEPIECE
Voltages in each antenna are transferred into a big grid, with sa mpling done ever y 20 nanoseconds. High-speed digital electronics performs fast transfor mations on sampled data. The prototype of this inexpensive scope was tested in West Forks, Maine, in dark skies near Canada. Tegmark needs to raise $100,000 to scale up to the next stage. Within a few years, he hopes to build the Omniscope, a square-kilometer array. While a typical scope has spherical aberration and a small field of view, the Omniscope would collect data from horizon to horizon and would be omni-chromatic and omni-directional. The Omniscope would be far cheaper to build than a similarly-sized single-dish radio telescope or a standard interferometer. A large number of antennas are needed to capture the very faint signal of neutral hydrogen left over from the early universe. This neutral hydrogen can be seen everywher e if the frequency knob on the scope is turned far enough. When space expands by a factor of 10, 21-cm. radio wa ves become 210 cm long. Tegmark wants to make a 3D map of the universe using redshifted survey data to be obtained from the Omniscope. Data from the early universe could further constrain Omega, the cosmological parameter defining the curvature of space. Tegmark's earlier research using SDSS data, in conjunction with other scientists, measured the spatial curvature as equal to 1.003 plus or minus 0.010. "This number Omega in cosmology measures whether space goes on for ever or curves back on itself. " "Since we've tested this thing out and it really works, I know we ca n do it because all we have to do is build and buy mor e copies of exactly the same stuff which alrea dy Tegmark continued on page 12

Scientists Will Look Even Further Back in Time, AAA Told
By Lynn Darsh
Although we know more about the early universe than ever, the best is yet to come, Dr. Max Tegmark, professor of physics at MIT, told the AAA October 1. Inaugurating the club's 2010-11 lecture series at the AMNH with a talk on "The History of the Universe in One Hour," Tegmark cited recent results such as precision measurements of the cosmic micr owave background by the Wilkinson Microwave Anisotropy Probe (WMAP) and thr ee-dimensional galaxy maps from the Sloan Digital Sky Survey (SDSS), which has mapped mor e than 100 million galaxies over a large part of the celestial spher e. Precision data have ma de cosmologists believable, Tegmark observed. The combination of advances in space technology to capture data in differ ent wavelengths from above Earth's atmospher e, in detector technology to improve sensitivity by 100 or even 1,000 times, and in computer technology to ma nipulate this large amount of infor mation, has produced a revolution. Tegmark's research plans include looking much farther back in time, earlier tha n SDSS (which he has worked with), at the epoch before galaxies had for med. He spoke just after returning from successfully testing the prototype of a Fast Fourier Transfor m Telescope (FFTT), designed in collaboration with Matias Zaldarriaga, professor of astronomy and physics at the Institute for Advanced Study in Princeton. The FFTT is a type of interfer ometer functioning as a digital telescope. It uses inexpensive modular TV antennas to search for redshifted 21 cm. radio waves given off by neutral hydrogen in the early universe. These modular, inexpensive antennas are arranged in a square grid.


What's Up
By Tony Hoffman The Sky for November 2010
November's Meteors. Two meteor showers grace our skies this month. The Leonids peak November 17. Prime time for observing begins after the waxing gibbous Moon sets around 3 p.m. It's expected to be a typical (non-stor m) year for the shower. Observers at dark-sky sites can see about 20 Leonids an hour radiating from the backwards question mark that represents the lion's head. The Leonids are debris from Comet 55P/Tempel-Tuttle. Earlier in the month, a lesser -known meteor shower, the Taurids, holds swa y. This shower, really two r elated showers, is associated with Comet Encke. The Taurids show some activity late September to early December, and show an extended peak. The shower should be at its best on moonless nights early in the month, when between five and 15 slow-moving meteors, including a relatively high percentage of fireballs, can be expected. Planets Everywhere. Five planets are on view this month. Jupiter lies to the southeast at nightfall benea th the Circlet of Pisces, and is visible most of the night. The planet fades slightly, from mag -2.8 to -2.6, as it slowly pulls away from Earth after its closest opposition in 50 years. Two other planets grace the evening twilight. Mercury and Mars can be seen together low in the southwest November 20, when they lie less than 2 degr ees apart. Their apparent motion takes them in opposite dir ections. Mars is lost in solar glare by month's end, while Mercury climbs into easy visibility above the twilight. Saturn climbs out of the pr eda wn glare. Its rings are much wider open than when we last saw it a few months ago. Saturn lies in Virgo, between stars Theta and Gamma Vir ginis. Venus emer ges from solar glare into the mor ning sky, below Spica, the brightest star in Virgo. Venus is unmistakable, blazing at mag -4.4, brighter than any object nor mally visible except the Sun and Moon. November November Earth, 1:25 November November
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November November November November November November November November November November Earth, 1:56

7 Moon lies near Mars in evening twilight. 9 Mars is closest to Antares. 13 First-quarter Moon at 11:39 a.m. 15 Mercury lies 2 degr ees from Antares. 16 Moon lies near Jupiter. 17 Leonid meteor shower pea ks. 20 Mars and Mercury lie 1.7 degr ees apart. 21 Full Moon at 12:27 p.m. 28 Last-quarter Moon at 3:36 p.m. 30 Moon is at perigee, 229,553 miles from p.m.

Jupiter Rules the Evening Sky
By Joseph A. Fedrick
In September, the Earth passed closer to Jupiter that it has in ma ny years. Jupiter loomed big and bright in the evening sky during September and October. It was the only bright planet visible in the late evening sky. Venus was visible near the southwest horizon in la te August and early S eptember, but by October was too near the horizon to be seen from my location after sunset. Mars was also too near the horizon and hidden in the solar glare this fall. Saturn also was lost in solar glare. Mercury ma de a brief morning appearance in September but then slid back into the solar glare, heading for a solar conjunction and then a poor autumn evening apparition. Jupiter was close enough in September so I could see, with only my 60mm r efractor at 100x, Europa's shadow transiting the Jovian disk. Europa is the smallest Galilean satellite to cast a shadow r egularly on the Jovian disk. The South Equatorial Belt was still a very faint bluegray during S eptember and October, while the North Equatorial Belt was a dark orange-brown. The Great Red Spot still maintained a relatively deep dark salmon redpink a nd was visible even with my 60mm r efractor at 100x. The spot stood out not only because of its deeper red color, but because the S outh Equatorial Belt that partially envelops it was still faded to near invisibility. Use of my reveal much through the blurry at the six-inch Newtonian r mor e detail because turbulent autumn air higher resolution of Fedrick eflector at 150x didn't fair -to-poor viewing caused Jupiter to be the six-inch scope. I continued on page 12

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Liftoff of Shuttle Discovery, 4:40 p.m. Moon is at perigee, 226,298 miles from m. Moon lies near Saturn in morning sky. New Moon at 12:52 a.m.


A Message from AAA President Richard Rosenberg
Hello members: Ther e's a chill in the air. Our lecture series has begun. Starfest was terrific. It must be membership -r enewal time! The good news is we're continuing to grow, approaching 400 members. The ba d news: Donations to the club are down, probably because of the recession. Our dues remain $25 a year, but it won't stay that way without your help. Bring friends to our events. They ma y develop an interest and join. If you have Internet access, please receive Eyepiece by e-mail. Almost 100 members have done so, but more than 200 haven't. The cost of printing and mailing Eyepiece is significa nt. The online version has links to related websites. Post our flyer on the lectures at your office or a nearby school or library. If you don't have a flyer, let me know. Although fall mea ns a tinue obser ving sessions, Rego Park in Queens. In total eclipse of the Moon hiatus of some outdoor activities, Floyd Bennett Field, Fort Greene and Great Kills will conand we'll probably meet occasionally at the High Line in Manhattan, Pier 1 in Brooklyn a nd December we'll be at Belvedere Castle in Central Park and a location yet to be chosen for the the mor ning of December 21.

Our indoor events, including the lectur e series and the seminar, will continue. Thanks to NYU, we have pizza and soda at the seminar on the second Thursday of the month. Another sign of the season: We've order ed copies of the "Obser ver's Handbook 2011" for $19.95 each. If you'r e interested in this fine combination of refer ence material and infor mation on next year's sky events, contact me. Rich Rosenberg, president@aaa.org, (718) 522-5014

AAA's December Lecturer to Discuss Phoenix Mission to Mars
Dr. Suzanne M. M. Young, chemistry instructor at the University of New Hampshire, will addr ess the AAA Friday, December 3 on "Top 10 Discoveries of the Phoenix Mission to Mars and the Implications for Biohabitability." The fr ee public lecture begins at 6:15 p. m. in the Kaufma nn Theater of the AMNH. "The [2007-09] mission had a goal of sampling to deter mine whether this environment may have been habitable for life at some time," Young notes. "The presence of water ice in the regolith was confir med. Salts offer evidence for the presence in the past of liquid water. An evaluation of habitability is a requir ement for sending any mission to search for life. The major discoveries of the mission will be discussed in evaluation of those requirements for life." Young did research for the mission for several years. She helped design instruments and develop experimental procedures, and was science plan integrator at mission control during the operation, both primary and extended. Other AAA lectures : January 7, Robert Nemiroff, Michiga n Technological University, "Best Astronomy Pictures of the Day, 2010." 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. " Dupree's talk will be the annual John Marshall Memorial Lectur e, which honors a past president and executive director of the AAA. Marshall died in 1997.
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Panelists Delve into Factors that Make the Earth Unique
By Maya Kushner
There's usually one Isaac Asimov Memor ial panel a year, but in honor of The Rose Center's 10th anniversary, a special Asimov pa nel held the stage March 10 to discuss "Is Earth Unique?" Speakers wer e selected for their diverse expertise in geology, biology, chemistry and physics, and the wa y they've applied these fields to addr ess the existence a nd future of Earth. Moderator and Hayden Planetarium dir ector Dr. Neil DeGrasse Tyson began by speaking about the discovery of Gliese 581g, believed to be the planet with the greatest likelihood of having conditions suitable for liquid water at its surface found to date within the habitable zone of its star. He stressed the importance liquid water has to the origin of life as we know it. Don Br ownlee, professor of anatomy at the University of Washington, said "the Earth is undoubtedly rare" due to its liquid nature. Although liquid metha ne exists on Titan, "one would feel less at home on Titan than on Mars." So there are other qualities necessary for life, said Brownlee, who studies origins of the solar system. Paul G. Falkowski, professor of geological and marine sciences at Rutgers University, discussed the importance of volcanoes and the role they play in maintaining our atmospher e. Plate tectonics is important in this cycle since the crust gets reheated and comes out through volcanoes, perpetuating the nitrogen/oxygen cycle. Tyson noted that life itself has a tendency to "infuse" our atmospher e with nitrogen and oxygen. Life as elemental as bacteria exists in gr eater quantity in our lower colon than all the people who have ever been bor n. Chris Mckay, a.k.a. "Mr. Mars" of the NASA Ames Research Science Center, discussed life on other planets. If findings show an "independent origin of life"--i. e., a "second Genesis"--that would help show life is a natural feature of the universe, he said. Fred Adams, professor of Michigan, an expert on t for mation and the dyna mics planet for mation, said stars
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to for m solar systems. An estimated 20%-50% of stars have planets. Tyson noted there may be other ways to sustain life that we haven't thought of. Two factors brought up by the panel wer e self-replication of the species and its metabolism. Mckay said Darwinia n replication and mutation repr esent life. Minik Rosing, professor of geology at the University of Copenhagen, who wor ks on Earth's early history and the influence of life on Earth's evolution, suggested looking back to the Earth/Moon system mor e tha n 3.8 billion years ago, wher e complex organisms ha d a chance to flourish. Panelists generally agreed that geology and plate tectonics are big factors in keeping the Earth active, as are volcanoes producing the carbon in our atmospher e without which the Earth would freeze (as is the case with Mars, which lost its atmospher e). Mass is yet another factor which creates a set of physical properties for a planet, and influences its evolution. Distance from the host star is another variable. And Rosing noted the ocean floor is continually hydrated thr ough our ocea ns, which lubricates the ma ntle and influences plate tectonics. Adams mentioned the difficulty in cr eating a controlled-fusion r eaction, which nature does readily in stars and galaxies. Another factor to look at is the importance of Earth's ma gnetic field in protecting and sustaining life. Although Earth during its evolution temporarily lost its magnetic field, those times don't line up with ma ss extinctions. This suggests the ma gnetic field ma y not be as important as originally thought. In fact, it was suggested that without one, cosmic-radiation particles would cause mor e frequent mutations, and might move the presence and continuation of life along quicker.

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.

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physics at the University radiative signature of star circumstellar disks during ve to have the right mass


AMNH's Astronomy SciCafe: The Next 50 Years in Space
By Greg Matloff
If you've never attended a Science CafИ, you've missed a treat. These fun events demonstrate ther e is a NYC audience for innovative science. On October 6, AMNH astrophysics curator Dr. Micha el Shara entranced a crowd at the Gottesman Hall of The Planet Earth at the museum with an infor mal discussion of huma nity's space future. Shara began his interactive talk by describing his research on stellar explosions and collisions, his work at the Rose Center designing shows and exhibits, and his previous work with the Hubble Space Telescope r esearch tea m. He briefly reviewed huma nity's space effort during the last 50 years. During this time, weapons have been converted to space vehicles, and humans have flown in space and visited the Moon. The main astrono mical result of the Apollo program was greater understanding of lunar and solar -system origins. Although the post-Apollo era has spurred international cooperation, the U. S. may have lost its nerve in space, Shara stated. China may now lead the wa y. Another great U. S. accomplishment, he noted, is the Hubble Space Telescope. With this instrument--which will be deorbited in 5-7 years--we've seen solar systems in for mation and plumbed the depths of extra -galactic space. Humans ha ve demonstrated their role in space during Hubble servicing missions. We're now gearing up for Hubble's replacement. The James Webb Space Telescope (JWST) will have about 10 times the Hubble's light-gather ing power. The JWST won't be in low-Earth orbit like the Hubble but will sit at a gravitationally stable Lagrange Point about 1 million miles distant. Unlike the Hubble, the JWST won't experience day/night therma l variations and will ther efore be a superior infrared (IR) instrument. Equipped with sunscreens, IR detectors will likely r equir e no liquidnitrogen coolant. Very distant galaxies and star clusters, and other highly redshifted objects, should be observable. Shara expects huma ns will visit the JWST and other telescopes in trans-lunar space even though such telescopes are designed to be non-r epairable. Regarding an eventual r eturn to the Moon, Shara believes commer cia l-government-internationa l collaborations might cut costs. But he expects that China will visit the Moon befor e our astronauts return there. Building a lunar observatory is one goal for explorers. One concept is an IR telescope of kilometer dimension in a lunar crater. Construction of such a huge device could be accomplished using a slowly rotating turntable sprayed with an ionic liquid. Such material should rema in liquid at low temperatures and be highly reflective. Although such a lunar telescope wouldn't be affected by atmospher e, lunar dust is an issue. Electrostatic fields could clear dust from the mirror surface. Using such a conceptual device, Manhattan-sized features could be resolved on planets 20-30 light-years distant. Although huma ns might ultimately mine the Moon for water in polar craters, Helium-3 might be a mor e lucrative lunar export. Present at low concentrations in lunar regolith and very rare on Earth, this isotope could be exported to Earth using a lunar space elevator and fused with deuterium to end the energy crisis. Unlike terrestrial space-elevator proposals, low lunar gravity allows application of stainless steel, and space debris is no problem. Lunar mining could concentrate on the lunar far side to conser ve the Moon's visual appearance. Main obstacles to human deep-space flight include cosmic radiation, psychologica l effects and bone degr adation caused by extended periods of weightlessness. Although weightlessness ca n be alleviated in a spinning spacecraft, the best solution to all these factors is improved in-space propulsion to reduce travel time. Eventually, crews could visit the Martian moons Deimos and Phobos. One of these small bodies could be maneuver ed into Mars-stationary orbit and used to anchor a Mars space elevator. According to Shara, such a device might enable colonization and terraforming of Mars. More distantly, humans might explore the ice-shrouded ocea ns of Europa, and the Kuiper Belt. Beyond that, they ma y colonize planets circling "nearby" stars. Shara suspects we are the galaxy's first spacefaring civilization.
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A Boffo Birthday for the Hayden is Rated a 10 -10-10
By Katherine Avakian
As twilight falls, the large spher e in the Hayden Planetarium, seemingly suspended in space, glows in a soft blue light, beckoning the viewer to come and explor e the infor mation the planetarium holds about the universe. Last month, the planetarium celebrated its 10th anniversary with a series of events, and on October 10, it buzzed with activity all day for visitors of all ages. Director Dr. Neil deGrasse Tyson welcomed visitors and noted it's also the 75th anniversary of the original Hayden. A little later, a birthday cake was enjoyed by all as the Chromatics sang "Happy Birthday" (a nd other favorites thr oughout the after noon). The audience viewed a short video of the entir e known universe mapped through astronomical observations. Tyson noted the video would show "empty areas not mapped yet because we don't know ever ything, not even the r eflectivity of the ocea n." The audience also viewed the three top videos out of numer ous submissions in a contest aimed at showing "how science has affected your life." The winner featured a sophisticated treatment of the Large Hadron Collider, which Tyson deemed "not only of entertainment value but of educational value." A question-and-answer session with Tyson is always dramatic, and this one was no exception. It quickly became obvious that children aren't afraid to challenge him. Tyson relishes this and the ensuing back-and-forth ener gizes both. Eight-year-old Sebastian brought up the subject that won't die: Pluto's status. Tyson gave sever al reasons why he believes Pluto to be a Kuiper Belt object, such as: It consists mostly of ice, as do other bodies in the outer solar system, and ther e are six moons in the solar system larger than Pluto, including our Moon. Sebastian was won over. Someone asked what happened to the old Zeiss Mark VI, which pr esented sky shows in the old Hayden; the much mor e sophisticated and technologically advanced Zeiss Mark IX now operates in the Space Theater. Tyson said Zeiss Mark VI was given to another planetarium "in a kind of planetarium organ-donor program." Ther e wer e ongoing activities throughout the day. A
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table was crowded with childr en for ming planets and other hea venly bodies out of clay. Saturn was a favorite, due to its rings, and it appeared in a variety of versions and colors. Childr en at another table folded shiny paper into space rockets. It was also fun to try out weight scales. One-year-old Madeline ma naged to get on the one for the Sun and found she would weigh a hefty 450 pounds ther e. Stepping on the nearby scale for a neutron star instantly zoomed one's pounds into the trillions. The Big Bang Theater's new presentation is a brief and spectacular journey to the Big Bang and back. Narrated by Liam Neeson, it travels to the ver y beginning, wher e in a nanosecond, the universe gr ew from an entity "smaller than an atom to astronomical size. " The digital pr esentation moves through the universe's dark period to the Cosmic Micr owave Background, the afterglow of the Big Bang, when the universe beca me transparent. As it returns to the present, the program dir ects the viewer to the already-fabled circular Cosmic Pathway, a 13-billion-year timeline of the universe. Each foot covers 45 million years. Although the long pathwa y seems spare of detail, its last tiny interval never fails to stun. In the space of only a few centimeters, it notes the first appearance of the hominid fa mily 4.5 million years ago, the appearance of homo sapiens ("anatomically modern huma ns") 100,000 years ago and, in the width of a strand of hair, the record of human art and creativity within the last 30,000 years. Earlier, Tyson said, "Exhibits that are bigger than you are, you remember forever." The Willa mette Meteorite ma kes one think how the fragment of a shattered planet made its fier y entry to Earth, wher e "over ma ny centuries rainwater interacted with its iron sulfide deposits, producing sulfuric acid" and burning large round cavities, creating a wonderfully tactile object. The r eplica of the Mars rovers makes one wonder what's happened to these intrepid travelers since they landed in 2004. Spirit is west of Home P late, wher e it's gone to sleep to try to recharge its batteries since falling silent in March. Opportunity has just cover ed another 100 meters (328 feet) in its trek to Endea vor Crater.


Review: Twin Voyagers Continue Our Quest for Discovery
By John Delaney
At first glance, one would assume that "Voyager: Seeking Newer Worlds in the Third Great Age of Discover y" by Stephen J. Pyne (Viking Penguin, $29.95) focuses exclusively on the most famous pair of NAS A space probes to traverse the solar system and beyond. In fact, the book offers much more. It uses the journeys of Voyagers 1 and 2 as a lens to scrutinize the essence of exploration itself, from the first forays of Europea n seagoing explorers to the a mbitious expeditions of the Space Age. The vehicles of discovery have cha nged, Pyne notes, but the social drivers, motivations and huma n nature itself rema in the sa me. The twin voyager spacecraft form the central narrative of the book. Only the 18th Century journeys of Captain Cook can claim so ma ny first encounters and discoveries, including new moons, ring systems, magnetospher es, even weather phenomena. The book contains a detailed saga of the Voya ger story, beginning within the sa me Cold War context that launched Sputnik, Explor er and Apollo. During this period, NASA researchers calculating potential gravity-assisted trajectories around the planets spied a golden opportunity: a rare alignment of the solar system occurring only once ever y 176 years. The two Voyager probes were launched in summer 1977. Like earlier chroniclers of Voya ger, Pyne enumerates its ma ny firsts. But rather than dwell largely on aspects of the mission, technology and discover ies, he compares and contrasts Voya ger explorations and other robotic planetary missions with earlier themes of discovery. In the era of Columbus, Cortez a nd Magellan, journeys into the unknown wer e driven by commer ce and conquest. In Pyne's second age of discover y, the quest becomes scientific, and the explor ers are often naturalists such as Charles Darwin and Alexander von Humboldt. The third age involves machines, those ma nned by astronauts and submariners, or remotely controlled robots in the depths of the ocea ns and space. One signature discover y of the Voya ger spacecraft --the volcanoes of Io--becomes one of the more successful themes of the book. Pyne points out that volcanoes loom large in the minds and travelogs of explorers dating to the first age. Many islands wer e volca nic. Von Humboldt's travels represented the beginning of the science of plant geography. The discovery of active volcanoes on Io lent the Voya ger mission a narrative device both exotic and traditional. Similarly, the discovery of nitrogen geysers on Neptune's moon Triton seems to connect different periods with a common thread. And the gravitational corridors of the Third Age echo the currents and winds of the first and second ages. Unlike previous eras of discover y, the Voyagers wer e unma nned space probes traveling through an abiotic medium. They encounter ed no other societies and sailed "serenely on autopilot, unworried, and unafflicted by lethargy and ennui." But in a sense, Pyne notes, much of Voyager's planning was geared for a public audience. While stunning ima ges of Jupiter, Saturn, Uranus and Neptune are clearly Voyager's most salient legacy, ma ny scientists were originally opposed to including camer as. Fortunately, cameras were included and photos were indispensable for geological and meteorological comparisons with earthly phenomena. Voya ger 1's ima ge of Earth from outside the solar system was a highlight. In spite of Voyagers' lack of a huma n crew, the craft are the crowning achievement of planetary exploration. Never again will so many worlds, and their staggering diversity of features and weather, be experienced by researchers for the first time. Voyager 2 was successfully redir ected to Uranus and Neptune, providing data on planets unlikely to receive additional visits anytime soon. And the spacecraft press on, gathering infor mation on the "soft geography" within the solar system's heliosheath, wher e solar and interstellar winds meet. For all its renown as an exemplar of successful technology and collaborative, government-supported science, the Voya ger program contains at its core the root of all journeys, according to Pyne, nothing less than a mecha nical manifestation of the huma n quest in keeping with literary traditions that include the Odyssey and other epics. One major differ ence: For Voyager, there's no return, but its images and data have profoundly increased our knowledge of the outer planets and for ever cha nged perceptions of the solar system.
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Briefs: Earth-size Planet is Found in Star's Habitable Zone
An Earth-size planet has been spotted orbiting a nearby star at a distance that would ma kes it not too hot and not too cold--comfortable enough for life to exist. If confir med, Gliese 581g would be the first Earth-like world found in a star's habitable zone, a region wher e a planet's temperature could sustain liquid water on its surface. Astronomers are optimistic about prospects for finding life there. Gliese 581g is one of two worlds discover ed orbiting red dwarf Gliese 581, upping that nearby star's planets to six. The other newfound planet, Gliese 581f, is outside the habitable zone. The star is 20 light-years away in Libra. Gliese 581g is an estimated 0.15 AUs from its star, close enough to be able to orbit in just under 37 days. Gliese 581 pla nets orbit in nearly circular paths. Gliese 581g has an estimated mass three to four times Earth's. From the mass and estimated size, the world is probably a rocky planet with enough gravity to hold onto an atmospher e. The planet is tidally locked to its star, so that one side basks in perpetual daylight while the other remains in darkness. This locked configuration helps stabilize the planet's surface climate. Any emer ging life for ms would have a wide range of stable climates to choose from and to evolve around, depending on their longitude. Average surface temperature may range from 24 below to 10 degr ees. New measurements of Kitt Peak National Observatory night-sky brightness show that, despite metro Tucson's rapid growth, sky brightness has remained constant for 20 years. This suggests strengthened lighting or dinances by Tucson and Pima County have been effective in suppressing skyglow caused by outdoor lighting. Kitt Peak is just as dark as Palomar was in the 1970s, when it was consider ed a premier dark observing site. Kitt Peak sky brightness measured over hea d actually decreased slightly from 10 years earlier. Maintaining lightpollution levels will requir e stricter controls and enforcement outside a nd within Tucson and Pima County, the study says. Most big, super-hot alien planets being sought in old star clusters may have been destroyed long ago, a new study suggests. These hot Jupiters wer e likely ripped apart by tidal forces that caused them to spiral into their own stars. In the cramped orbit of a hot Jupiter, the huge planet's gravitational pull can create a tide, or bulge, on its parent star. As the planet orbits, the star's bulge points
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a little bit behind the planet and essentially pulls against it. This reduces energy of the planet's orbit, moving the planet a little closer to its star. Then, the star's bulge enlarges and saps more ener gy from the pla net's orbit. This process continues for billions of years until the planet crashes into the star or is torn apart by its gravity. An unmanned Chinese Moon probe blasted off October 1 to begin the country's next phase of lunar exploration and set the stage for mor e ambitious spaceflights to come. The Chang'e 2 probe is the second step in China's three-phase Chang'e Moon-exploration program. It will test technology and collect data on possible landing sites for Chang'e 3, scheduled to land in 2013. Chang'e 2 swooped down to an orbit nine miles above the surface to take high-r es pictures of landing areas for Chang'e 3. Chang'e 2 then went 62 miles up to conduct a study of the lunar surface and dirt. The craft will take a close look at the Moon's Bay of Rainbows, or Sinus Iridium, which has been proposed as a potential la nding site for China's next Moon mission. One of Mars' two moons most likely formed from rubble catapulted into space after a comet or meteor ite sla mmed into the planet, a new study finds. Researchers used data from the ESA's Mars Express spacecraft to study P hobos' composition. They found P hobos and asteroids don't seem to be made of the sa me material. Instead, the moon has ma ny minerals also on Mars, suggesting a common origin. The tea m also found phyllosilicates--minerals that can for m in the presence of water--on Phobos. They've been detected on Mars. By tasting rocks and air on Mars, the Phoenix la nder discover ed secr ets about the history of water ther e during the last 4 billion years. Carbon dioxide shows evidence of recently interacting with liquid water. When combined with studies of 4-billion-year-old Martian meteorites on Earth, results suggest Mars has experienced substantial interactions between r ock and cold water throughout its history. Scientists used Phoenix' observations of carbon dioxide isotopes in Mars' atmospher e to study its water history. A new model of Venus' atmospher e suggests gr eenContinued on page 9


Briefs: Moon Got Mauled by Space Rocks, Crater Data Show
Continued from page 8 house gases may be cooling the pla net's interior. These gases initially cause temperature to rise, but at a certain threshold, they ca n trigger processes in the crust that cool the ma ntle and overall surface temperature. Scientists exa mined interaction of carbon dioxide and other gr eenhouse gases in Venus' atmospher e and concluded the planet ma y ha ve been hotter than today. But at a certain point this process turned on its head: High temps caused partial mobilization of the Venusian crust, leading to an efficient cooling of the ma ntle, and volca nism strongly decreased. This resulted in lower surface temperatures. A new study shows how severe a beating the Moon has received from space rocks. Scientists have created the first compr ehensive catalog of large lunar craters, a detailed study of minerals and ha ve identified areas of unusual silica-rich composition. Lunar Reconnaissance Orbiter data include 5,185 craters at least 12 miles in dia meter. Data revea l areas most pockmarked, repr esenting older surfaces. Researchers discover ed the oldest regions are the souther n near side and the north-centr al far side. South Pole-Aitken seems to be the oldest basin. Lunar water may put a major crimp in pla ns for telescopes on the Moon. As molecules of Moon water vaporize in sunlight, the scattering process could heavily distort observations, a new study found. A spiral galaxy 60 million light-years away could help astronomers better understand the Milky Way because of a central bar-like structure. Galaxy NGC 1365, in Fornax, is one of the most-studied barred spiral galaxies. A new photo may help deter mine if the Milky Way contains a central bar. NGC 1365's huge bar structure disturbs its gravitational field's shape, which causes regions of gas to compress and trigger star for mation. Unraveling of a knot in a mysterious ener gy ribbon shows the edge of our solar system is much mor e dyna mic than previously thought. NASA's Interstellar Boundary Explor er spacecraft has revealed quickly cha nging conditions near the heliospher e, a protective bubble that shields our solar system from cosmic rays. The heliospher e has been shrinking recently, likely because the solar wind, which inflates it like a bubble, has been wea kening. As the heliospher e shrinks, it's a less good shield. More galactic cosmic rays can find their way in. A study has found evidence of a cannibal star that recently devour ed a companion star or planet, possibly spawning a second generation of exoplanets. BP Pisciu m (BP Psc) is a mor e-evolved version of our Sun, but with a surrounding disk of dust and gas usually associated with young stars. Such disks are thought to give rise to planets. Because BP Psc is relatively old, the disk is a myster y. Scientists suggest BP Psc, about 1,000 light years away in Pisces, appropriated the disk from a younger neighbor it gobbled up. Even if BP Psc is killing off some of its planets, it could be spawning r eplacements. A second round of exoplanets may be growing from the star's disk, hundr eds of millions of years after the first round of pla netary for mation. Ancient Mars once had surprisingly frigid primeval ocea ns complete with their own icebergs, new evidence suggests. This supports the idea of a cold and wet ancient Mars, gover ned by ocea ns or seas cover ed partly in ice, as well as glaciers and massive polar caps. The pr esence and distribution of certain boulders and chains of craters could have been caused by rock fragments carried by iceber gs. Glaciers in the highlands could have eroded the terrain, transporting rock within them and on their surfaces. If there wer e iceber gs, ther e wer e open and sizable bodies of stable liquid water on the surface. Scour marks 0.6-3 miles long in the norther n plains and Hellas Basin could also be evidence of iceber gs. Mysterious icy jets erupting from Saturn's moon Encela dus may ha ve their roots in a bubbly ocean flowing beneath the fr ozen surface, a new study finds. This salty subsurface sea could feed violent geysers, supplying them with water, gas, dust and heat before sinking back to the dark depths. The geysers are associated with Encela dus' "tiger stripes," huge fissures in the icecover ed surface. Cassini has also found the geysers contain water vapor, sodium salts, potassium salts and carbonates, suggesting a sea of liquid water flows benea th the icy crust. The probe's observations revea led huge amounts of heat flowing through the tiger -stripe region. Continued on page 10
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Briefs: Titan May Contain Complex Organic Molecules
Continued from page 9 A salty sea under the surface has gases dissolved in it, theory goes. The sea water flows up to and through the tiger-stripe fissur es, its pressure drops and the gases bubble up, making the ocean fizzy. The relatively warm water and expanding gas feed the jets. When the bubbles pop, they thr ow off a fine spray that contains salt and other materials. Then the sea water, having dumped much of its war mth on surface ice, cools and sinks back through cracks, rejoining the ocea n and its heat transferring circulation system. The hazy atmosphere of Titan, Saturn's largest moon, may contain complex organic molecules that are the building blocks of life as we know it, a new study suggests. Researchers simulated possible chemical reactions high in Titan's nitrogen-rich atmospher e. They found various complex molecules, such as amino acids and nucleotide bases, could for m without liquid water or a surface. The upper atmospher e has all elements necessary for complex, inter esting, Earth-like chemistry to take place: huge molecules, some with 1,000 carbon atoms; oxygen; and bombardment by solar radiation powerful enough to break chemical bonds and spur reactions. Results suggest the upper atmospher e could be a reservoir of prebiotic molecules. Scientists have discovered water ice on an asteroid for the second time, suggesting it's mor e common on rocks in our solar system tha n thought. Two tea ms found evidence of water ice and organic molecules on 65 Cybele just six months after discovering water ice on asteroid 24 Themis. Results suggest asteroids ma y ha ve deliver ed much of these essential materials for life to the early Earth. Scientists aren't sure wher e they ca me from, but one possibility is the asteroid's subsurface. Astronomers have the first confir med snapshots of what appears to be the after math of an asteroid collision. When scientists first discover ed P/2010 A2 in the asteroid belt in January using the Rosetta spacecraft, the fa ct that it trailed a tail made them think it was a comet. A closer look, however, suggested it was something more peculiar: Hubble ima ges revealed it ha d a bizarre Xshape nucleus. Astronomers suspect a rock 10-16-feet
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wide sla mmed into a larger asteroid at speeds of 11,200 mph. The smaller asteroid was vaporized, stripping material from the larger one. Pressure from solar radiation then swept the debris behind the r emna nt asteroid, for ming a comet-like tail. Hubble ima ges suggest the nucleus of the object is 390 feet wide, with its tail containing dust grains 1-2.5 millimeters large, enough material to ma ke a ball 65 feet wide. Computer models suggest the collision took place around F ebruary 2009. Five of Saturn's inner moons are pelting each other with particles that leave bright, colorful splotches and ma y be the source of a Pac-man feature on one of the moons, Mimas. Cassini recently spotted reddish and blue splashes on the icy surfaces of Mimas, Enceladus, Tethys, Dione a nd Rhea. The colors are helping scientists map out how material travels between these moons, and they're highlighting how "space weathering" can impact bodies in the solar system. Scientists used Cassini ima ges from 2004 to 2009 to produce high-res global color maps of the five moons. The maps incorporate images shot through visible-light, ultraviolet and infrared filters. The chief aggr essor appears to be Enceladus. Mysterious ice geysers blast from its south polar region. Particles from these icy jets make up most of Saturn's misty E ring, and they also appear to splatter Tethys, Dione and Rhea. Enceladus' spray also tags Mimas, but it hits the moon's trailing side. Some of Enceda lus' own icy material blows back onto the moon. A chain of bluish splotches along Rhea's equator reopens the question of whether Rhea ever had a ring. An ancient meteor strike on Mars has revea led the first direct evidence of how warm liquid water may have shaped a habitable under ground environment. Mars Reconnaissance Orbiter ima ges have r evealed the first carbonate rocks found inside Leighton Crater at a level once buried four miles below the surface. Carbonates hold carbon dioxide and can form rea dily in the presence of water, but have previously been found only in a few scatter ed locations on Mars. This first-time discover y of carbonates in an under ground location points to a warmer epoch in the ancient Martian past with mor e atmospher ic carbon dioxide, as well as ancient seas. The ancient rocks may date back as far as 3.5 million-4 billion yea rs. The findings may also prove a huge step toward solving the mystery of methane gas on Mars.


Events on the Horizon November 2010
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. Saturdays, November 6, 13, 20, 27, evening Observing at Inwood Hill Park, Manhattan, P, T, C Next dates: Saturdays in December. Thursday, November 11, 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: December 9. Friday, November 12, 8-10 p. m. Observing at Floyd Bennett Field, Brooklyn, P, T, C Next date: December 10. Saturday, November 13, dusk Observing at Great Kills Gateway National Park, Staten Island, P, T, C Next date: December 11. Saturday, November 13, dusk-9 p. m. Observing at Fort Greene Park, Brooklyn. Monday, November 15, 7:30 p. m. Hayden Planetarium lecture, P, AMNH In "The Road to Stardom in the Milky Way," Paul Goldsmith, NASA project scientist for the Herschel Space Observator y, will discuss evidence that indicates star for mation is an ongoing process, look at reservoirs of material from which stars are made, and study steps in the transfor mation of cold, molecular gas into dense, hot stellar materia l. Wednesday, November 17, 7 p. m. Quarterly AAA board meeting, M, HQ All members are invited to attend. Saturday, November 20, 10 a. m.-noon Solar Observing at Central Park, P, T, C At the Conservator y Waters. Next date: December 18. Tuesday, November 30, 6:30-8 p. m. Hayden Planetarium event, P, AMNH "Grand Tour of the Universe" with Brian Abbott of the Hayden. Wher e are we among the stars in the Milky Way? Fly through the Digital Universe Atlas and exper ience the entire observable universe.

Obama Space Plan Closer to Reality
President Obama last month signed legislation that turns his vision for U.S. space exploration of asteroids and Mars into law. The signing makes official a NASA authorization act that scraps the agency's previous Moon -oriented goa l and paves the way for a manned mission to an asteroid by 2025. A manned mission to Mars is envisioned for some time in the 2030s. The bill also calls for a budget of $19 billion for NAS A in 2011, adding one extra space shuttle flight befor e the fleet retir es next year, and the extension of the ISS through at least 2020. The plan calls on NAS A to retire its three-shuttle fleet in 2010 and begin wor k on a new hea vy-lift rocket, which will be requir ed to launch big components of future deep-space missions. It also sets the stage for the rise of commer cia l spacecraft. Under Obama's plan, NASA will rely on Russian, Europea n and Japanese spacecraft for its space-station cargo and crew transportation needs in the near term, then use American, privately built spacecraft to ferry astronauts to the ISS once they become available. The bill authorizes, but doesn't appropriate, $58.4 billion for NASA for fiscal years 2011, 2012 and 2013.
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Tegmark continued from page 1 works. By the very nature of the design of this telescope, it is completely modular. You also learn a lot about ways in which you can impr ove the design by building a small prototype before building the full thing." Cosmologists "take measurements of how galaxies are clustered and compare them with what comes out of calculations" from theories. Six cosmological parameters "deter mine all of cosmology. Another 26 define all of particle physics. Thirty-two numbers describe our universe. It's ver y important to test these and see possible values they can ha ve." One of the parameters is the "matter budget," what the universe is ma de of: 21% dark matter, 4% atoms of ordinary stuff, 75% dark energy. This is a "quantitative exa mple of how rapidly measurements have improved." Tegmark showed how incr easingly precise data have enabled researchers to refine error boundaries around cosmological parameters. He said the indication that space isn't just really big but truly infinite is "a shocking surprise". The implications of inflation include a multiverse, or parallel universes. Tegmark said mor e da ta ma y be available in the next few years that could provide the smoking-gun evidence that inflation is the right theory.

Islip Adopts Lighting Regulations
The town of Islip October 13 beca me the third Long Island town this year to adopt new restrictions on just about every aspect of outdoor lighting, following Southampton and Southold. The Islip rules include specifications for parking lots, ATMs, service stations, flag spotlights and holiday lighting. Homeowners are required, wher e possible, to use outdoor lights no stronger than 100 watts and to angle them no more than 45 degrees from vertical. Businesses that close by 9 are requir ed to turn off exterior lights within 30 minutes of closing. Within 10 years--immediately for all new construction and renovation--homes and businesses must have lights confor ming to a policy that requires nearly all exterior lights brighter than 100 watts to be no higher than 20 feet from the ground and shielded to prevent light from escaping on the top and sides. Fedrick continued from page 2 barely ma de out South Temperate Belt irregularities. I slewed my six-inch scope just north and east ter October 10 to see Uranus. It looked blurry at I used a lens yielding 75x and saw Uranus as a non-stellar featureless pale gray-gr een-blue disk. of Jupi150x, so tiny but

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