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Journal of the Amateur Astronomers Association of New York November 2008 Volume 56 Number 11, ISSN 0146-7662

EYEPIECE
By examining other planetary star systems, Low said, we get to see if our solar system is typical. Star formation happens [relatively] quickly, with interstellar gas and dust cooling to form planets within the planetary disk. Over time, stars form [then die], and after a few generations make metals [and rock] needed to make planets. Interstellar gas and dust in the molecular clouds surrounding a young star collide and stick together to build ever-larger bodies. But what exactly is the glue that holds matter together to form planets? Recent studies of boulders moving through gas have revealed two effects. First, turbulence in the gas causes the boulders to clump in high -pressure regions. Second, gas drag causes further clumping as the boulders in the densest regions start pulling gas and nearby debris in with them. Simulation experiments of gas drag within gas clouds cause further clumping of the boulders. It has been shown that orbiting boulders concentrated so strongly that gravitational attraction between boulders caused them to collapse into large planetesimals that aren`t affected by gas drag. Experiments have also shown dust balls or dust bunnies (like the ones under your bed) can clump together very easily in near-vacuum conditions. From a few microns to meters, dust can form into sand, to pebbles, to rocks, then to boulders. Rocks could also build up to boulders and then grind back down to dust. The whole process may take 100,000 years, but probably much longer. Once rocks and boulders form into planetesimals, they can begin to accrete more efficiently, Low said. Planets continued on page 12

Astronomers Shed New Light on Planet-Forming Process
By Thomas Haeberle
Ever wonder what gives rise to the birth of planets? For generations, astronomers have argued how planets have formed. How do large boulders manage to stick together and bind into asteroid-size planetesimals before being pulverized by other objects within a protoplanetary disk? Dr. Mordecai-Mark Mac Low, associate curator and chair of the department of astrophysics at the American Museum of Natural History, believes he has a pretty good idea. He elaborated at the kickoff lecture of the AAA`s 2008-09 lecture series October 3 at the museum. Recent modeling developed by Low and other astrophysicists from the museum and the Max Planck Institute for Astronomy in Heidelberg, Germany (as well as astrophysicists from a number of other universities) has shed new light on this fundamental part of the planet-forming process. Earth is made of rock which isn`t a very common thing in the universe (or matter for that matter). There is one atom for every 10 to the 27th cubic meters of space. Low went on to explain about the discoveries of planetary star systems by other astronomers such as San Francisco State University`s Dr. Geoffrey Marcy. As of October 2008, 313 extrasolar planets, or exoplanets, have been detected and confirmed, and of these, the lowest mass is five times more massive than Earth. He mentioned Dr. Ben Oppenheimer and other colleagues at the museum and their trailblazing work to develop new technologies for telescopes capable of seeing planets around stars. Such work is paving the way for a new generation of space probes such as the Terrestrial Planet Finder.


What's Up
By Tony Hoffman The Sky for November 2008
Venus, Meet Jupiter. Even as Jupiter has been slipping into the southwest in the early evening sky, Venus has been ever so slowly creeping out of the solar glare. At the end of the month, these two brilliant planets meet in eastern Sagittarius. On November 30, Venus will pass two degrees south of Jupiter, when they should both be visible in a low-power eyepiece. Venus, although about 6 times brighter than Jupiter, is only half the apparent diameter of that giant world. (As an inner world, Venus receives and reflects much more light than distant Jupiter.) Venus` small disk will appear gibbous, about twothirds illuminated, while Jupiter--as usual--will be full, and appear slightly squashed at the poles. Its retinue of four bright moons should be visible as well. Cowardly Leonids and Torrid Taurids? In most years, the Leonids are the best November meteor shower, but the Leonid meteor storms around the turn of the millennium are over, and this year a right gibbous Moon will hamper viewing on the morning of November 17. Still, dedicated meteor watchers will want to observe in the predawn hours that day, just in case. Meanwhile, the lesser-known Southern Taurids, remnants of Comet Encke, have the potential to put on an impressive show. This shower, which radiates from western Taurus to the right of the Hyades star cluster, lasts from late October to early November, peaking around November 5. On at least three occasions, most recently in 2005, the Southern Taurids have experienced outbursts, notable for their slow-moving fireballs. (I believe I observed the 2005 outburst from Harriman State Park with several AAA members.) The Moon is largely out of the way during the peak period this year. November's Constellations. Summer stars are slowly departing, with Vega swinging down into the northwest, Aquila low in the west and Cygnus in its headfirst plunge toward the horizon. The Great Square of Pegasus stands near the zenith, with Andromeda trailing it out of the northeast. The Milky Way spans the northern sky from east to west. Fomalhaut twinkles low in the south, while Cetus climbs in the southeast and Aries in the east. Perseus and Cassiopeia are high in the northeast. Auriga,
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marked by brilliant Capella, rises in the northeast, with Taurus well to its right. Orion and Gemini rise a few hours after sunset, and Sirius and Procyon join the show before midnight. November 1 Moon lies near Venus. November 3 Moon lies near Jupiter. November 5 Southern Taurid meteor shower peaks; First-quarter Moon at 11:03 p.m. November 13 Full Moon at 11:17 a.m. November 14 Moon at perigee. November 17 Leonid meteor shower peaks. November 19 Last-quarter Moon at 4:31 p.m. November 21 Moon lies near Saturn. November 27 New Moon at 11:55 a.m. November 30 Venus lies 2 degrees from Jupiter.

Saturn Returns to the Morning Sky
By Joseph A. Fedrick
Saturn was approximately 5 degrees east of Regulus in Leo when I saw it approximately one-quarter degree from Mars on July 10 at in the same field of view at 50x with a wide-field-view eyepiece in my 60mm refractor. When I next saw Saturn after it emerged from the solar glare in the morning sky in October, it was 15 degrees east of Regulus. I first saw Saturn in autumn on the morning of October 2 around 6:10 a. m. By October 4 at 6:10 a. m., the rings were more nearly edge-on than I have seen them since the mid 1990s. I could barely perceive them as a ringlike structure at 100x in my 60mm refractor and the Cassini division wasn`t discernible at all. The dull outer A ring and brighter inner B ring were barely discernible as separate structures. The ring system, as a whole, appeared dimmer than in recent years when the visible face of the rings was tilted more into the sunlight. Very faint brownish cloud belts in both hemispheres of Saturn were barely visible against the dull yellow disk of the planet in less than optimal seeing as Saturn was still within 25 degrees of the horizon. The coming weeks promise dramatic changes in the appearance of the ring system as it will be even more nearly edge-on during November.


A Message from AAA President Richard Rosenberg
Hello, members: Good news! We are about to sign an agreement with the Solaria condominium in tory with an 8-inch Meade telescope. We`ll provide staffing for observing sessions hood schools and help design the children`s playroom with an astronomical theme return, residents in each of the 65 units will become AAA members. Credit for this dent Michael O`Gara. Riverdale. It has a rooftop observaand lectures, outreach to neighbor(are there any artists out there?). In win -win deal goes to former presi-

Our next AAA lecture takes place on Friday, November 21. Note the late date; the Kaufmann Theater was unavailable the two previous Fridays. The speaker is Capt. Daniel Burbank of the U. S. Coast Guard, who served as a specialist on the STS-106 and STS-115 missions to service the International Space Station in 2000 and 2006. Capt. Burbank will fully detail what was involved in servicing the ISS. It should be exciting to meet an astronaut. At the next two meetings of our Observers` Group, Bruce Kamiat and Julian Parks will give presentations on asteroids. On November 22, Bruce will talk about families of asteroids, believed to form from collisions. He`ll point out some craters on Earth thought to be impacts of these bodies and will bring a few actual meteorites. Julian, who will speak at the following meeting December 20, will describe the mineralogy and classification of asteroids. He`ll also show how to find the brightest asteroid, Vesta, which can now be spotted using binoculars. The Observers` Group meets from 1 to 4 p. m. at AAA headquarters, 1010 Park Avenue. A beautiful celestial event is coming. Venus and Jupiter approach each other throughout November. After the Moon, they`re the two brightest bodies in the night sky. On November 30 and December 1, they`ll be closest to each other, only 2 degrees apart (the width of two fingers held at arm`s length). The Moon is to the right on the first night, but the next day joins the two planets in a tight, beautiful gathering. On the first of these two nights, Sunday, November 30, we have an event scheduled in conjunction with the Central Park Conservancy. Join us at 5 p. m. at the northern end of the Great Lawn to see the planets. At 6, we`ll head to Belvedere Castle, where I`ll give a talk, followed by observing of the early winter sky in the plaza. We`ll also probably do something the second night. When we decide, we`ll post it on our website (www.aaa.org). If you`re not connected to the Internet, call me. Rich Rosenberg, AAA President, president @aaa.org, (718) 522-5014

AAA To Hear Ex-Astronaut Discuss 2006 ISS Mission
Coast Guard Capt. Daniel C. Burbank, who has served as an astronaut on two space-shuttle missions, will address the AAA Friday, November 21 to discuss STS115: An Assembly Mission to the International Space Station. The free public lecture begins at 6:15 p.m. in the Kaufmann Theater of the AMNH. This lecture will discuss the process of preparing and completing an International Space Station (ISS) assembly mission aboard the Space Shuttle Atlantis, from pre-flight training through wheel stop,` Burbank says. The audience will be taken through simulator training, launch, robotics assembly and the spacewalks required to install and activate a school-bus-sized electrical power module critical to completing assembly of the ISS. Burbank was an astronaut on the 2006 STS-115 mission, when he was flight engineer and lead shuttle robotics operator, part of the team that delivered and activated a truss/electric-power module to the ISS, and on mission STS-106 in 2000, when he brought equipment and supplies to the ISS and configured ISS systems for arrival of the first ISS Expedition Crew. Burbank was a missionspecialist astronaut working in support of space-shuttle and ISS programs at the Johnson Space Center from 1996 to 2006 and held Coast Guard posts before that. He is currently professor of engineering at the Coast Guard Lecture continued on page 11
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Annual Custer Jamboree Hears Dava Sobel on Galileo
By Tony Hoffman
On the eve of the International Year of Astronomy in 2009, the 400th anniversary of when Galileo first turned a telescope to the heavens, it was timely that Dava Sobel, author of Galileo`s Daughter and Longitude, spoke at the two-day 30th annual Custer Jamboree in Southold, L. I., last month on How Galileo and the Telescope Changed Everything. Galileo Galilei, a Tuscan mathematician, teacher and instrument maker, built a telescope from a description of one that Venice`s scientific advisor had been shown. The telescope (or looker) had been invented by eyeglass maker Hans Lippershey, who had sold the device to the Dutch army in 1608. When word got out, many inventors created their own. Although Galileo didn`t invent the telescope, he is credited with being the first to systematically study the night sky with one. In the fall of 1609, he trained his primitive scope on the Moon, and was astonished to find it uneven, rough, full of cavities and prominences. He observed the phases of Venus, realizing that our sister world orbits the Sun, a reinforcement of the Copernican theory that would later put him at odds with the Church. He viewed the rings of Saturn, which he wasn`t able to fully resolve, thinking them perhaps a pair of large moons, one to either side of the planet. He also discovered four stars near Jupiter, which he came to realize were in orbit around the planet. Sobel noted that he first called them the Cosmian Stars after his patron and former pupil Cosimo de Medici, the Grand Duke of Tuscany, and later the Medicean Stars. We now know them as the Galilean moons: Io, Europa, Ganymede, and Callisto. Sobel also related a tale of Galileo and Kepler. Galileo announced his discoveries in the form of Latin ciphers. Kepler was one of the few who made serious attempts to translate them. His translations, though wrong, were strangely prescient. He took the one announcing the phases of Venus to mean that there was a red spot on Jupiter--the Great Red Spot wasn`t discovered until 50 years later-- and the announcement of Saturn`s rings to mean that Mars had two moons; it does, but they weren`t discovered until 1877.
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Two other speakers were Dan Davis and Guy Consolmagno, co-authors of Turn Left at Orion, a book to help amateurs with small telescopes find celestial objects. Davis, a professor at SUNY Stony Brook, discussed the creation of the book and his long friendship with his co-author. He and Consolmagno, now a Jesuit brother working at the Vatican Observatory, met in the geology department at MIT. Since the fourth edition of the book will soon be printed, the authors solicited opinions from the audience on several ideas they had: extending the guide to cover the full southern sky, adding fainter objects within range of modest Dobs, and spiral binding and laminating the book for outdoor use were among them. Consolmagno also spoke on Latest News from the Asteroid Belt: Fluffy Asteroids in Sculpted Orbits. When he was assigned to the Vatican, he became curator of its observatory`s meteorite collection. He measured the density and porosity of these bodies, and compared these characteristics with what we know about the asteroids from which many of them originated, to gain insight into how small bodies in the solar system formed and evolved, as well as the origins and evolution of the solar system as a whole. He also discussed what we know of characteristics of planets orbiting other stars. Consolmagno splits his time between the Vatican observatory in Arizona and the one at Castel Gandolfo in Italy. In a talk titled Promise Them the Stars, Yale astronomy professor Dr. Michael Fairston spoke about the unique role astronomy can play to inspire both children and adults to care about science. Dr. Mike Inglis, astronomy professor at Suffolk County Community College, gave a well-illustrated talk, How Many Ways Can Black Holes Kill You? The short answer: many. I did some observing through Custer`s large, domed refractor. In back is a shed with an imaging telescope used to seek exoplanets. Custer also hosts small, domed observatories for two Long Island clubs: the Amateur Observers` Society of New York and Astronomical Society of Long Island. The Institute is working on automating its telescopes so they can be remotely controlled.


Club President Discusses Diverse Subjects in Radio Interview
By Richard Rosenberg
I had the good fortune to be interviewed by George Bodarky for his show Cityscape, a weekly feature on WFUV (90.7 FM), Fordham University`s radio station. I met George at his studio on the Fordham campus in the Bronx on October 14 and spent almost an hour answering his questions about amateur astronomy. The show was broadcast October 18. Of course, the absurdity of being an amateur astronomer in New York City came up. I explained to George that the Moon and bright planets can be enjoyed as much from the city as from a dark site. For example, on December 1, the Moon, Venus and Jupiter will form a tight grouping that will be a delight to the naked eye. But if you want to see galaxies or other faint celestial wonders, head about 100 miles away. When observing in the city, find an open area with a view of most of the sky. Avoid nearby lighting if possible. Look for parks and locations along the waterfront. Needless to say, New York City is plagued by light pollution. I explained that replacing current lighting fixtures so that all light is directed downward where it`s needed would result in a tremendous improvement and save energy at the same time. I pointed out many people interested in the skies buy or receive as gifts poorly-designed telescopes. As a rule, when shopping for telescopes or binoculars, stay away from department stores. Look for a place with knowledgeable employes. Camera stores usually fit the bill. George inquired about the danger of an asteroid hitting Earth. I mentioned the chance of a major catastrophe is small but an unknown object could destroy a city or create a tsunami. As a result, astronomers have been active in observing programs dedicated to discover as many of these minor planets as possible. Another topic was travel to the stars. I pointed out the nearest star other than the Sun is a little over 4 light years, or 25 trillion miles away! But if our descendents figure out a way to travel at near-light speed (when, relativity says, time slows down), it may be feasible. To hear the entire 20-minute broadcast, go to the WFUV website at http://wfuv.streamguys.us/cgi-bin/ colinker.cgi?colink=100818466840758.

Observers' Handbook
The 2009 Observers' Handbook from the Royal Astronomical Society of Canada is available to club members at a discounted price of $17.95. The club has purchased 25 copies for distribution on a first come, first served basis. Contact president@aaa.org. The handbook (www.rasc.ca/handbook/) has been published since 1907 and is regarded as the standard North American reference for data on the sky. Its two main sections are Upcoming Astronomical Events and Astronomical Reference Information. The latter includes new sections on the electromagnetic spectrum and sky phenomena.

Federal Lighting Specs
Specifications calling for the full shielding of solidstate luminaire street lights will be included in proposed criteria for the federal efficiency program Energy Star. If passed, the pending requirements will have a major impact on the design and marketability of future streetlights. These criteria are the result of input from a series of Energy Department-sponsored workshops in July. International Dark-Sky Association technical advisor Pete Strasser informed DOE of the necessity of such a design. In fully shielded outdoor luminaires for outdoor pole/ arm outdoor street and public lighting, the guidelines propose that the "luminaire shall deliver 100% of total lumens within the 0°-90° zone, with a maximum of 10% of total lumens delivered within the 80°-90° zone." In lay terms, these are standards for total dark-sky compliance. Energy Star's consideration of this standard signals official recognition of the environmentally positive capabilities of fully shielded light fixtures and helps ensure that future public fixtures will be energy-efficient and darksky friendly.
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New Global Steps Are Advocated on NEO Protection
After a two-year study involving a cast of international experts in government and science, the Association of Space Explorers Committee on Near-Earth Objects (NEOs) has completed a proposal, Asteroid Threats: A Call for Global Response, to encourage the international community to set up procedures to protect the Earth from asteroid impacts. The study recommends that a global, coordinated response by the United Nations to the NEO hazard should e ns ur e t ha t t hr e e func t i ons a r e pe r f or me d: 1. An information, analysis and warning network should be established. This network would operate a global system of ground- and/or space-based telescopes to detect and track potentially hazardous NEOs. The network, using existing or new research institutions, should analyze NEO orbits to identify potential impacts. It should establish criteria for issuing impact warnings. 2. A mission planning and operations group, drawing on the expertise of spacefaring nations, should be established and mandated to outline the most likely options for NEO deflection missions. It should assess the current, global capacity to deflect hazardous NEOs by gathering necessary NEO information, identifying required technologies and surveying NEO-related capabilities of interested space agencies. In response to a specific warning, the group should use these mission plans to prepare for a deflection campaign. 3. The United Nations should exercise oversight of the above functions through an intergovernmental NEO threat oversight group. This group would develop policies and guidelines that represent the international will to respond to the global impact hazard. The group should establish impact-risk thresholds and criteria to determine when to execute a NEO deflection campaign. It would submit recommendations to the Security Council. Two of the three elements needed to respond to the impact hazard, involving surveys and development of deflection technologies, are underway at some level. The emphasis is thus on the third element, an global decisionmaking process to manage complex political-technical issues of how to respond to impact threats.

Watching an Eclipse--and More--from a Rain Forest
By George Hripcsak
My family traveled to Monteverde, Costa Rica for February vacation, visiting some friends. Their children's school, the Monteverde Friends School, put on a star party for the lunar eclipse with my Pronto 60mm telescope as the main attraction. Monteverde is a cloud forest, high in the air, lush and wet. It boasts monkeys, exotic birds, snakes, frogs, butterflies, scorpions (in the bedroom), army ants, and some unrecognizable animals. Even though it was dry season, most of the week was cloudy and misty, not surprisingly for a cloud forest. On the night of the eclipse, somehow we had clear skies. A number of children and their families showed up for the event. We started off in the bright light of the full moon. Attendees noticed how quickly the Earth's shadow seemed to cover the Moon. The orange color of the shadow was obvious fairly early, and the fully eclipsed Moon appeared quite bright. As totality approached, the sky darkened and many stars appeared. The hazy horizon
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obscured the Large Magellanic Cloud, but I could see stars just above it in Carina, Pictor, Puppis and Vela. Despite the eclipse, the big hit was Saturn. Attendees couldn`t believe it was real. Mars was just a disk, but it had its own appeal. M42 was pretty, and the Pleiades were great in the wide-field Pronto. The crowd left about mid-totality, and I hopped around the sky until the Moon returned.

Contacting the AAA
If you want to join, volunteer, participate in events, have a question or change your address, e-mail members @aaa.org, or leave a message at AAA hq: (212) 5352922. Also, visit us on the web at www.aaa.org. If you want to write an article for Eyepiece, contact editor Dan Harrison at editor@aaa.org or (914) 762-0358.


Review: A Team Effort Got the Hubble Up and Running
By Lynn Darsh
In "The Universe in a Mirror: The Saga of the Hubble Space Telescope and the Visionaries Who Built It, (Princeton University Press: $29.95), science writer Robert Zimmerman has written a well-researched, clear and absorbing history about the dogged efforts of the Hubble`s creators to get their vision realized. He tells a compelling story of the politics and the personalities, the career aspirations and the sacrifices of the astronomers who got the Hubble funded and operational. It has been over 60 years since Lyman Spitzer envisioned a large space telescope in his 1946 paper, Astronomical Advantages of an Extra-terrestrial Observatory. Enough time has passed for Zimmerman to evaluate the successes and failures of key scientists and engineers, the impact on their careers of the Hubble experience, and the rewards and sometimes undeserving sidelining of key contributors. Spitzer turned down the opportunity to be project scientist in 1971, and instead recommended Robert O`Dell, chairman of the University of Chicago`s astronomy department, to design and construct the telescope structure. O`Dell`s determination was matched by the Institute for Advanced Studies` John Bahcall`s splendid and time consuming advocacy of the Hubble. Together they undertook a years-long effort to lobby Congress for funding, energizing legions of astronomers in the process. Zimmerman recounts the generosity, vision and determination of Hubble team members. After O`Dell is forced out and loses the valuable perk of Hubble telescope time, each original observing team gives him some observing time so he has a fair share for research. O`Dell, in turn, splits his time with Spitzer, who backed an old technology in competition with new CCD cameras and so never became part of a research team. The result is an engrossing tale of how the space telescope got built and how astronomy became a national priority. This thoughtful history offers a balanced look at NASA`s flawed project management and assesses its serious problems and spectacular successes. Zimmerman identifies budgetary finagling, byzantine governmental bureaucracy and human fallibility of administrators and technicians that led to initial optical problems with the Hubble`s primary mirror. He describes a Perkin-Elmer technician`s improvised placement of three household washers in a bracket holding a lens in the null corrector (mirror tester) to take up 1.3 millimeters of unexpected slack. No one from NASA is around--they were busy fighting over budgets. No one looked into why the null corrector showed a lot more material needed to be ground off the outer regions of the primary mirror. Once Hubble was launched, and particularly after a servicing mission compensated for the mirror`s flaws, Everywhere scientists pointed Hubble it revealed a universe that was as beautiful as it was astonishing. Zimmerman is excellent on the impact of Hubble research. Photographs of Eta Carinae pre-Hubble and by Hubble underscore how clear, detailed imaging of a distant object makes leaps in knowledge possible for the researcher and accessible to the amateur. He asserts the greatest scientific impact of Hubble has been on cosmology, since the size and age of the universe have been measured and its accelerating expansion discovered. Zimmerman evaluates other legacies of Hubble. The way astronomical research is done has changed as universities have developed huge research consortiums. Telescopic data have become more standardized, as specialists staff telescopes and prepare electronic data streams for all researchers, who no longer need to be expert on an individual telescope`s instruments. Technological developments have impacted photography since CCDs have proliferated in commercial applications. The combination of human spaceflight and robotic technology were essential to the success of the Hubble and should be remembered by future space pioneers. Any doubts about Hubble`s appeal were dispelled by the outcry that followed announcement of plans to scrap it. In the end, the undeniable appeal of Hubble, the compelling nature of the unknown that it promised to unveil, was what finally won out, beating back every form of opposition or skepticism from untold naysayers while simultaneously compelling its supporters to make sacrifices surprising even to themselves.
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Briefs: Engineers Work to Get Hubble Back on Track
A week after two events caused a snag in NASA's attempt to revive the Hubble, it was nearly back up and running, with science operations set to resume towards the end of last month. The control systems were running but the instruments were still in safe mode. The new glitches cropped up while engineers attempted to switch to a backup data-relay channel in the Hubble`s science instrument control and data-handling system after the primary channel failed September 27. The data-relay channels allow the Hubble to send images back to Earth. The switch to the backup channel was a tricky maneuver that required the activation of five other backup systems that had been in hibernation since Hubble launched in 1990. The glitches postponed the October 14 launch of the space shuttle for its last Hubble repair mission until early 2009. NASA's MESSENGER probe began beaming back stunning new images from its successful second flyby of Mercury last month, capturing never-before-seen views. One image shows large patterns of ray-like lines extending southward across much of the surface from a young, newly-imaged crater. The previously-imaged Kuiper crater and other craters also have similar webs of lines radiating outward. Another picture is the highest-resolution color image ever taken of Mercury's surface. Details include a large impact basin with an 83-mile diameter. The first Mercury flyby in January looked at a different side of the planet. The Phoenix Mars Lander weathered its first dust storm last month, though the dust lowered the lander's solar power and put the brakes on some planned activities. The nearly 23,000 square-mile storm moved west to east around the northern arctic plains, and weakened considerably by the time it reached the lander October 11. After passing through Phoenix's landing site, the storm gradually decreased and power levels rebounded. Phoenix is already generating less energy than earlier in the mission because the Sun is dipping lower in the Martian sky as winter nears. The Phoenix Mars Lander spotted snow falling. Clouds and fog form each night as the air gets colder. A laser instrument detected snow 2.5 miles above the landing site. The snow vaporizes before reaching the ground.
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Scientists already knew it snows on Mars, but they`d never seen it happen from the ground. Meanwhile, scientists plan to fill the instrument's four remaining ovens with Martian dirt and ice samples. They want to get a pure-ice or ice-rich sample. Phoenix will also look for signs of organics in samples. The lander will scrutinize different isotopes in ice and water vapor in the Martian air to see if the two water sources interact. Phoenix will also try to sample dirt underneath a rock that it moved. Images have shown color differences in the dirt under the rock. Several minerals have been identified that suggest the surface there has interacted with water in the past. Instruments have shown the pH of soil near Phoenix is about 8.3, almost exactly the pH of oceans on Earth. NASA's Mars Odyssey probe received a two-year extension through September 2010. The longest-serving of six spacecraft orbiting Mars first reached the planet in 2001. Its extended mission requires changing orbit to gain a better vantage point for doing infrared mapping of Martian minerals. An orbital adjustment should allow Odyssey to look down at sites in mid-afternoon rather than late afternoon. The craft's thermal camera could then be better able to detect infrared radiation from warmer rocks. Scientists studying the Martian landscape say rivers ran through it. The planet also seems to have experienced rain. The rivers may have cut deep valleys in the Martian highlands near the equator, and left calling cards elsewhere. Three Mars spacecraft spotted signs of valleys with fan-shaped river deltas inside ancient craters. Researchers focused on possible ancient river valleys crisscrossing the Xanthe Terra highland region. One 3-milewide crater contains possible proof in the form of a fanshaped delta, where the Nanedi River flows into the crater from the south. Researchers also counted the number of craters to roughly determine the age of planetary surface in the area. Their crater count revealed water flowed through the valleys 3.8 billion-4 billion years ago. Crater sediment deposits formed in no less than a few hundred thousand years. Valleys flowing into and out of craters have allowed researchers to be reasonably certain there were lakes on Mars. Continued on page 9


Briefs: Saturn's Rings May be Older than Thought
Continued from page 8 Parts of ancient Mars may have been wet for 1 billion years longer than scientists previously thought, a new study suggests. Previous studies suggested water runoff had ceased after the first billion years of Mars' history. But now scientists think rains and floods persisted into more recent geologic periods. They examined images of the plains surrounding the Valles Marineris canyon system, and noticed light-toned layered deposits in the plains around Valles Marineris had different features from those inside. This suggested water continued to flow on a tangible scale in these plains from one epoch into another until approximately 3.7 billion to 3 billion years ago. For the first time, scientists have discovered a giant cyclone on Saturn's north pole, and observed a similar storm on the south pole with 10 times greater detail than before. The storms are hundreds of times stronger than giant hurricanes on Earth. Dozens of puffy, convectively formed cumulus clouds swirl around both poles, betraying giant thunderstorms beneath. Researchers think the cyclones are powered by heat released from condensing water in the thunderstorms. Unlike Earth's hurricanes, Saturn's cyclones have no body of water at their bases. Time-lapse movies of the clouds circling the north pole show the cyclone there is rotating at 325 mph, more than twice as fast as the highest winds measured in cyclones on Earth. Saturn's rings may be much older and more massive than previously thought. Computer simulation showed how the rings could date back billions of years to the early solar system, rather than 100 million years ago, as previous observations suggested. The calculations are consistent with recent ring observations by Cassini­ Huygens. Scientists modeled how meteorites smash into the rings, shattering ring particles and coating each in a layer of ice and dust. Before, scientists had assumed this shattering led to eventual dissipation of the rings, but a new simulation shows that after breaking up, the particles could clump together in a perpetual recycling process. Previously, researchers had thought the rings were relatively young because they appeared bright and pristine, not covered with the detritus of billions of years of meteorites smashing into them. But the new calculations show that if the effect of this clumping and re-clumping is taken into account, the dust would also be recycled through the rings and wouldn't appear as dark as might be expected. A very small asteroid streaked into the skies over Sudan October 7, burning up in the atmosphere and creating a show. This was the first time an asteroid impact has been predicted with near certainty. The space rock, about 6 feet in diameter, posed no risk to those on the ground. The fiery entry appeared like a very bright shooting star. It was visible from eastern Africa traveling rapidly across the sky from northeast to southwest. The effect of the atmospheric impact was the release of about 1 kiloton of energy. Astronomers have confirmed the weight of the most massive star in the galaxy: roughly 116 times the mass of the Sun, dwarfing most other stars in the Milky Way. The next most massive star is about 89 solar masses, gravitationally bound to the record setter. The next most massive is 83 solar masses. Theory says stars can be up to about 150 solar masses. The new measurements are rough, and the stars might be considerably heavier or lighter. The larger weighs 116 plus-or-minus 30 solar masses; the smaller weighs 89 plus-or-minus 15 solar masses. Astronomers hope to refine these calculations with future observations. The binaries are in the star cluster NGC 3603 in the Carina spiral arm of the Milky Way, around 20,000 light-years from our solar system. The two stars are thought be Wolf-Rayet stars, very hot, heavy and evolved stars that appear to be losing much mass in a stellar wind, similar to our Sun's solar wind, but stronger. Astronomers have sighted a very dense planet-sized object that orbits its parent star in just four days and six hours. COROT-exo-3b fits into the category of a brown dwarf, but scientists haven`t ruled out that it`s a planet. The object`s mass is 20 times Jupiter`s but it`s roughly the same size. It`s outside the range of planets and stars discovered to date, with the largest planets having 12 times Jupiter`s mass and the smallest stars 70 times the Continued on page 10
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Briefs: `Dark Flow' May Explain Movement of Some Matter
Continued from page 9 mass of Jupiter. The dwarf planet previously known as 2003 EL61 is now Haumea, after the Hawaiian goddess of childbirth and fertility. Discovery of football-shaped Haumea was announced in 2005. Haumea also represents stone, and observations found it to be composed almost entirely of rock with a pure ice crust. Haumea has the same diameter as Pluto but is 32% of Pluto's mass. Scientists suggest Haumea's long, narrow shape arose from its rapid spin; it rotates about once every four hours. Haumea is now 50 times as far from the Sun as Earth is, but its orbit can swing it as close as 35 times. It`s part of the transNeptunian class of cold and rocky objects in the outer solar system. Two small companion objects, thought to have been knocked off Haumea's body by impacts, keep the dwarf planet company. The moons are now called Hi'iaka and Namaka, after the two children born to Haumea. A new 3-D view has demystified some of Venus` powerful winds. The European Space Agency's Venus Express tracked hidden cloud movements within the southern hemisphere, and scoped out hurricane-like vortexes over the poles. Tracking them for long periods provided a precise idea of the wind speeds that make clouds move and of wind variation. Scientists followed 625 clouds at a 41-mile altitude, 662 clouds at a 38-mile altitude and 932 clouds at 28-29 miles. The team also discovered that wind speed could deviate from approximately 230 mph at the 41-mile altitude to 130 mph at 2829 miles. NASA Administrator Michael D. Griffin defended his agency's plan to establish a lunar colony before embarking on a manned Mars mission, arguing that those who prefer to focus only on Mars are overestimating what`s known about the Moon and underestimating the difficulties of going to Mars. Griffin said the Apollo program spent just 27 working days on the Moon, which he said is as big as Africa and merits substantially more exploration. Griffin wondered whether those who are strongly advocating efforts oriented towards Mars are fully cognizant of the difficulties sending astronauts to Mars and the amount of preparation needed before a mis10

sion is pursued. Patches of matter in the universe seem to be moving at very high speeds and in a uniform direction that can't be explained by any known gravitational force in the observable universe. Astronomers call the phenomenon dark flow. Whatever is pulling this matter must be outside the observable universe. Scientists discovered the flow by studying giant galaxy clusters. By observing the interaction of X-rays with the cosmic microwave background (CMB)--leftover radiation from the Big Bang-scientists can study the movement of clusters. The X rays scatter photons in the CMB, shifting its temperature. This effect hadn`t been observed in galaxy clusters before, but a team of researchers found it when they studied a catalog of 700 clusters, reaching up to 6 billion light-years. They compared this catalog to the map of the CMB taken by the Wilkinson Microwave Anisotropy Probe (WMAP) satellite and discovered the clusters were moving nearly 2 million mph toward a region between Centaurus and Vela. This motion is different from outward expansion of the universe, which is accelerated by dark energy. Around a distant star, two planets similar to Earth collided and were destroyed. The speculative scenario is based on a ring of debris around the star that includes 1 million times more dust than circles our Sun. Apparently, major collisions can take place in a fully mature planetary system. Researchers had assumed it was a young star, just a few hundred million years old, and the debris was left over from planet formation. But earlier this year, another study showed the star was actually a binary pair, and the stars were billions of years old. So why all the debris? The dust is about the same distance from the stellar pair as Earth is from the Sun, and given theories of planet formation, that debris should have been swept up into planets by now or pushed away by stellar radiation. A colossal collision must have created the dust sometime in the past few hundred thousand years and perhaps much more recently. If life was on either planet, the massive collision would have wiped out everything in minutes. A massive disk of infrared-emitting dust circling the star provides testimony to this sad fate. But two questions need to be answered: How do planetary orbits become stabilized in such an old, mature system, and could such a collision occur in our solar system?


Events on the Horizon November 2008
M: members; P: open to the public; T: bring your telescopes, binoculars, etc.; C: cancelled if cloudy; HQ: at AAA headquarters, 1010 Park Avenue (between 84th and 85th streets); AMNH: For ticket information, call (212) 769-5200 For directions to AAA observing events, check the club's website at www.aaa.org. Saturday, November 1, dusk Observing at Great Kills Gateway National Park, Staten Island, P, T, C Wednesday, November 5, 8-11 p. m. Observing at Prospect Park, Brooklyn, P, T, C Friday, November 7, 8-10 p. m. Observing at Floyd Bennett Field, Brooklyn, P, T, C Next date: Dec. 5.
Monday, November 10, 7:30 p. m. Hayden Planetarium lecture, P, AMNH

Friday, November 21, 6:15 p. m. AAA lecture, P Coast Guard captain and ex-astronaut Daniel Burbank will discuss STS-115: An Assembly Mission to the International Space Station in the Kaufmann Theater of the American Museum of Natural History. Next lecture: Dec. 5. Saturday, November 22, 10 a. m.-noon Solar Observing, P, C Conservatory Waters, Central Park. Next date: Dec. 20. Saturday, November 22, 1-4 p. m. Observers' Group, M, HQ First of two presentations on asteroids, Things that Sometimes Hit Us. Next date: Dec. 20. Sunday, November 30, 5-9 p. m. Special Observing Session and Lecture, P, T In cooperation with the Central Park Conservancy, the AAA will present a special astronomy event for families. At 5 p. m., we will gather at the north end of the Great Lawn to see a gathering of Venus and Jupiter, with the crescent Moon nearby. An hour later, we will head for Belvedere Castle for a lecture on astronomy, followed by observing on the plaza outside the castle. University, "Astronomy Picture of the Day"; February 20: Joseph Patterson, Columbia, "The Center for Backyard Astrophysics"; March 13: Neil deGrasse Tyson, Hayden Planetarium, "The Rise and Fall of Pluto-Witness to Demotion" (John Marshall Memorial lecture); April 3: Rick Fienberg, Sky & Telescope and Phillips Academy, "The More Things Change"; May 1: Denton Ebel, AMNH, "The Stardust and Genesis Sample Return Missions."
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Michael Brooks, physics consultant to New Scientist magazine, will explain scientific anomalies in his latest book of that title. He will discuss how the most baffling mysteries, such as the contents of the grandest galaxies, have led to our most significant breakthroughs. Thursday, November 13, 6-8:30 p. m. Recent Advances in Astronomy Seminar, M NYU, 239 Greene St., Room 801. Next date: Dec. 11. Wednesday, November 19, 7 p. m. Quarterly AAA board meeting, M, HQ All members are invited to attend. Lecture continued from page 3 Academy, from which he graduated. He has a master`s degree from Embry-Riddle Aeronautical University. Other upcoming AAA lectures are: December 5: David Hogg, NYU, "Automated Calibration of Astronomical Imaging and the Open-Source Sky Survey; January 2: Robert Nemiroff, Michigan Technological


Planets continued from page 1 It may take 30 million years for rocks to become planets, and tens of millions of years to get rid of the gas disk that surrounds a young star. Sheer instability within the planetary disk caused by turbulence can cause newly formed planets to spiral in towards the parent star as they lose angular momentum to the disk. Migration will stop once the gaseous disk is gone. Proof of migration is exemplified by exoplanetary star systems. This raises questions to how typical our own solar system is in the galaxy and whether other planetary systems are as stable. Further observations of these star systems will be required. "Our work provides the first scenario that appears capable of answering this gap in our basic understanding of planet formation, a process first identified over 30 years ago, Low said. This work raises new questions about how planet formation occurs in protoplanetary disks. Still, he and his colleagues believe the fundamental properties of gas-boulder interactions will provide the ultimate solution to this longstanding problem. Low concluded, The puzzle isn`t solved, but we can at least see a direction to go forward. Give us 10 years [for further observations] to see if our solar system is typical or not.

Program on Telescope Pioneer
Before we went to the Moon, George Ellery Hale took us to the tary on PBS beginning November ings), viewers will learn about the America`s first journey into space. American astronomer stars. In a documen10 (check local listtelescope pioneer and

The Journey to Palomar looks at the life of Hale, who built the biggest telescopes of the 20th century. Hale laid the foundation for today`s marvels. The Journey to Palomar traces Hale`s struggles to build the great telescopes at the Yerkes Observatory near Chicago, the Mount Wilson Observatory above Los Angeles and finally the million-pound telescope on Palomar Mountain near San Diego, considered the moon shot of the 1930s and `40s. It was a struggle to invent the technology, and Hale repeatedly sought to persuade the richest men in America, such as Andrew Carnegie and John D. Rockefeller Jr., to contribute to his vision of American astronomy. Hale's observatories drove America`s growing preeminence in science and technology. His observatories enabled the greatest discoveries since Galileo and Copernicus, like Edwin Hubble`s 1929 discovery of the expansion of the universe.

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