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Journal of the Amateur Astronomers Association of New York January 2010 Volume 58 Number 1, ISSN 0146-7662

EYEPIECE
farther away from us than the Moon. Type Ia supernovae demonstrate that the expansion of the universe is accelerating. This is the discovery of dark energy. Looking at Type Ia supernovae more deeply in space could measure evolution of that expansion rate for which general relativity provides predictions. "Isn't it amazing," he said, "that supernovas know the Balmer series? That hydrogen way back 3 billion years ago, emits a Balmer-series spectrum, just as hydrogen here today does?" This refers to the pattern of spectral lines, the electromagnetic waves that are stretched, or redshifted, into longer wavelengths while traveling through expanding space. The redder the light, the more expanding space they have traveled through--the farther away they are. So, analyzing data from supernovae 3 billion years ago provides you with the size of the universe. "What I love is that these used to be questions of religion or philosophy but today, it's an exact science." Edwin Hubble, kickstarting the field of cosmology as an exact science, observed galaxies and realized that fingerprint hydrogen spectral lines were redshifted far off towards the long-wavelength end of the spectrum. Thus, the interpretation of the expansion of the universe beat the steady-state model, in which the universe had been assumed as infinite and unchanging, not an unreasonable model considering that over most of the thouDark Energy continued on page 12

NASA, Energy Dept. Probing Dark Energy, AAA Hears
By Shana Tribiano
Dr. Charles Baltay is more than professor of astronomy and professor of physics at Yale. He is chairing a federal advisory panel for a joint NASA-Department of Energy (DOE) venture to find out more about the nature of dark energy. The panel had its first meetings on how to proceed last month. The Joint Dark Energy Mission (JDEM) marks the first time NASA and DOE have joint ventured. The two will seek to determine the best mission to undertake. Baltay, the AAA's December 4 lecturer at the AMNH, discussed the venture in his talk and in conversation afterwards. Against the backdrop of the search for dark energy and dark matter, Baltay noted that DOE has traditionally funded projects utilizing scientists, while NASA's focus is engineers. Put another way, the DOE tends towards particle physics and is experiment-driven, while NASA is more used to developing facilities for general purposes. DOE designs experiments to answer a question, while NASA puts hardware up. All this underscores the novel cooperation represented by the new venture. One key will be to measure Type Ia supernovae via the Supernova Acceleration Probe (SNAP), due to launch in 2015. Noting that understanding dark energy will grow from continuing what we've done so far, Baltay said that looking at Type Ia supernovae nearby more carefully will refine understanding of these objects. That is the Palmoar-Quest Survey. Looking at them more deeply in space and measuring the expansion rate of the universe as a function of time will mean probing the nature of dark energy. This is SNAP. SNAP is a proposed two-meter space-based observatory, sensitive to visible through infrared light, that will orbit at Earth's L2 Lagrangian point, about eight times

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What's Up
By Tony Hoffman The Sky for January 2010
Mars at its Finest. Even a relatively poor opposition of Mars, which occurs when the planet is near aphelion (farthest from the Sun)--as is the case this year--is cause for excitement among amateur astronomers. When opposite the Sun on January 29, Mars will blaze with a reddish glow at magnitude -1.3, a tad fainter than Sirius. Its disk will measure 14 arc-seconds, more than enough to reveal features such as the bright north polar cap and dusky markings to observers with relatively small telescopes. Mars starts the month in Leo and moves into Cancer by midmonth. At opposition, it's visible all night. Although it will then lie 61.7 million miles from Earth, nearly as far as the maximum possible separation at opposition of about 63 million miles, it will still put on a fine show, aided by its relatively high altitude in the sky. January's Constellations. Even as Mars climbs into the crisp January sky, Jupiter is preparing to depart. As the year begins, the solar system's largest planet lies in the southwestern evening sky among the dim stars of Capricornus, setting four hours after the Sun. By month's end, Jupiter will be in Aquarius, setting during late twilight. Pegasus swings westward as the sky darkens, while the Andromeda Galaxy is nearly overhead. Vega is low in the northwest as the sky darkens, trailed by Cygnus. The Swan appears to be plunging headfirst towards the horizon. Orion and Taurus are approaching the meridian, and Auriga is high in the east. This is a good time to monitor Epsilon Aurigae in its two-year-long eclipse. Gemini is high in the east. Mars stands well below Castor. Procyon, to Mars' upper left, forms a nearequilateral triangle with Mars and Castor. As the evening progresses, Regulus in Leo will rise; it can by found by extending a line downward from Castor through Mars. Last but not least is Sirius. The Dog Star culminates at midnight on New Year's Eve. It outshines the other fixed stars, and its blue-white brilliance, which flickers other colors of the spectrum (especially when Sirius is low), provides a contrast to steady, untwinkling red Mars. January 1 Moon at perigee, 222,875 miles from Earth, 3:33 p.m. January 4 Earth at perihelion, 91.4 million miles from
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the Sun, 7 p.m. January 3 Moon lies near Mars; Quadrantid meteor shower peaks. January 6 Moon lies near Saturn. January 7 Last-quarter Moon at 5:39 a.m. January 11 Moon lies near Antares. January 15 Mew Moon at 2:11 a.m.; annular solar eclipse visible from Africa, India and Southeast Asia. January 18 Moon lies near Jupiter. January 23 First-quarter Moon at 5:53 a.m.; Mercury at greatest elongation in morning sky. January 27 Mars closest to Earth. January 29 Mars at opposition. January 30 Full Moon at 1:18 a.m.; Moon at perigee.

Observing at the High Line
By Joseph A. Fedrick
The first part of the night of Tuesday, November 24 was clear for observers in downtown Manhattan. The Observers' Group (OG) met at club headquarters to look at some so-called Galileo scopes, plastic replicas of scopes similar to what Galileo would have used. The scopes weren't very user-friendly and at least one was missing a vital part so it couldn't be focused at all. It's remarkable that Galileo was able to show anything to people using those scopes. The meeting closed early so we could go to the High Line. This is an abandoned elevated railroad, part of which was converted into a landscaped promenade with good views of the Hudson River to the west, and southern and eastern skies. Michael O'Gara brought a 4-inch achromatic refractor. Someone else brought a 5-inch Schmidt-Cassegrain and two people brought Astroscans-short focal-length Newtonian reflectors. Michael's scope was pointed at the Moon and revealed sharp, contrasting views of many lunar craters and of earthshine on the dark side of the Moon. The Moon was near first-quarter phase. The SchmidtCassegrain was pointed at Jupiter and at 50x mag revealed two brownish equatorial belts and dusky gray polar regions as well as Jupiter's four Galilean moons. The image of Jupiter was disturbed by turbulent unstable air near the southwest horizon as Jupiter was rather low at around 9 p. m. when we were viewing. High Line continued on page 10


A Message from AAA President Richard Rosenberg
Hello, members: The AAA's fall class concluded with a trip to Ward Pound Reservation in Westchester County. The sky was as beautiful as the weather was cold. Shana Tribiano did a wonderful job teaching the class. We're debating what topics will be covered in the spring class. We may go into more detail in a few areas, or perhaps have a series of two-week mini-classes on different subjects with different instructors. If you're thinking of attending the class, I'd be interested in your ideas. Jason Kendall now chairs our seminar on recent events in astronomy. He succeeds Mary Carlson, who's done a superb job for the last several years. Mary will continue to attend and contribute. Even in the dead of winter we have observing. At 6:30 on Thursday, January 21, you're invited to be at the Charles Dana Discovery Center in Central Park (take the 2 or 3 train to 110th Street and Lenox Avenue). I'll give a short talk, followed by observing. We can always use more telescopes at these gatherings. Mars will be at opposition on Friday, January 29, and we'll probably do something special around that date. Check aaa.org. for the latest. As he does every month, Rik Davis will host solar observing in Central Park on January 30. I want to thank all of you who have renewed your membership. If you haven't done so, please do it now before you forget. Make use of the stamped, addressed envelope we've sent. These are obviously difficult economic times, but if you can manage a donation it will be put to good use. We still have copies of the Observers' Handbook 2010 available for only $17.45. I'll bring a few to the January 8 lecture at the AMNH. If you're interested but can't make the lecture, send me an e-mail or give me a call. Let me take this opportunity to wish you, your family and your friends a happy and healthy new year. To quote an old saying, may the wind be always at your back. Rich Rosenberg, AAA President, president @aaa.org, (718) 522-5014

AAA Lecture January 8: Best Astronomy Pictures of 2009
Dr. Jerry T. Bonnell, a scientist at NASA's Goddard Space Flight Center who co-founded the popular website Astronomy Picture of the Day (APOD), will present a selection of images featured on the site in 2009 when he addresses the AAA Friday, January 8 on "Skyscapes 2009". The free public lecture is at 6:15 p. m. in the Kaufmann Theater of the AMNH. APOD was originated and has been written, coordinated and edited since 1995 by Bonnell and Robert Nemiroff, a professor at Michigan Technological University. Its archive is one of the largest collections of annotated astronomical images on the Internet. It receives about 700,000 hits a day and goes out in 16 languages. Bonnell has worked on a variety of astrophysical satellite projects at Goddard. He currently works on the Fermi Gamma-ray Space Telescope project. Other lectures in the AAA's 2009-10 lecture series are: February 5: Arlin Crotts, Columbia University, "Liquid Mirror Telescopes Are Looking Up"; March 5: John Gianforte, Blue Sky Observatory, "In the Footsteps of the Master: Discovering the Contributions of Galileo"; April 9: Glynnis Farrar, NYU, "High-Energy Astrophysics with a Neutrino Telescope in New York City"; May 7: Ruben Kier, Advanced Radiology Consultants, "Best Targets for Amateur Astrophotography and What They Reveal About Our Universe."
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Interstellar Boundary Explorer Provides Useful Data
By Mary Carlson
Chair, AAA Recent Advances Seminar

NASA's Interstellar Boundary Explorer (IBEX) was a focal point of last month's Recent Advances in Astronomy Seminar. The project enables scientists to assemble the first comprehensive sky map of the solar system and its location in the Milky Way. Launched in 2008 and equipped with two particle-imaging cameras, it continually explores the nature of the interaction of solar winds and the interstellar medium at the solar system's edge. The unique view determines how researchers study interactive forces between the galaxy and the Sun. Six months of collections by IBEX's two detectors have provided data that have measured and counted energetic neutral atoms. These atoms were created in the interstellar boundary system caused by the clash between galactic material and ionized solar particles. The heliosphere, a protective bubble in space, shields the solar system from much of the lethal cosmic radiation surrounding it. NASA's recent findings include a narrow ribbon of bright emissions completing a nearly full circle across the sky. The density of neutral atoms in the band measures two to three times that in adjacent regions. The edge of the solar system, it seems, is quite different from previous predictions. Observations of that same area from Cassini, in its Saturnian orbit, find the band to be much broader than viewed by IBEX. No explanation has been offered. The ribbon as recorded by IBEX is 100-125 AUs from the Sun and runs perpendicular to the galaxy's magnetic field at the interstellar boundary. One idea is that this galactic magnetism has a much more powerful effect on the Sun's environs than earlier estimated and that perhaps pressure from the galaxy's magnetic field has forced particles just inside the heliosphere to crowd together. For years, scientists thought the high-speed solar winds created the structure at the heliosphere's boundary. New evidence from IBEX suggests that the galaxy's magnetic field, lying just outside the heliosphere, could play a main role in sculpting the structure of this region. The permanence of the emissions ribbon itself remains a mystery, just as its enigmatic form prompts controversy.

Scientists had originally hypothesized that pressure from the solar winds compacted the heliosphere in the direction the solar system moves through the galaxy, creating a comet-like tail in the opposite direction, an idea that's been revised. Its galactic pathway seems far from uniform and its shape quite unpredictable. To assess the safety of human space flight, a clearer understanding of our heliosphere is a must: how it varies in size as it travels through the galaxy and how it encounters regions of space with different densities and varying magnetic fields. Accurate data on its ability to filter out lethal cosmic rays are essential if we are to find our way as true voyagers in the cosmos.

`Visions of the Cosmos' at Rubin Museum
A leaf from a medieval manuscript depicting man at the center of the universe; a 12th-century sandstone sculpture of Vishnu reclining on a bed of serpents, afloat on the cosmic ocean; and photographs of galaxies taken from the Hubble are among 75 works on view in "Visions of the Cosmos: From the Milky Ocean to an Evolving Universe," which opened at the Rubin Museum of Art in Manhattan last month and runs until May 10. "Visions of the Cosmos" spans history and geography, delves into traditions of East and West, and examines ideas from religion and science. It's the first time the Rubin Museum, an institution devoted to Himalayan art, has displayed examples of European art. For an Eastern perspective, the museum looked to deity-centered cosmologies of Buddhism, Hinduism and Jainism, which envision gods as primary protagonists in the universe. The Western perspective includes images reflecting the human-centered cosmology of Christianity in the Middle Ages and the heliocentric universe embraced during the Renaissance. The intricate cosmic construct of the Kabbalah is also considered. The exhibition ends with photos representing current astrophysical findings and virtual travel through the universe via a digital simulation created by the American Museum of Natural History.

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AMNH Plays Role in Discovery of a Big Dipper Star
Next time you spy the Big Dipper, take a closer look at Alcor, one of the stars that makes the bend in the ladle's handle. It's been discovered that it has a smaller red -dwarf companion that you can't see. Alcor B orbits its larger sibling, caught in the act with an innovative technique called common parallactic motion by an international team that includes AMNH astrophysicists. "We used a brand-new technique for determining that an object orbits a nearby star, a technique that's a nice nod to Galileo," says AMNH astrophysicist Ben R. Oppenheimer. "Galileo showed tremendous foresight. Four hundred years ago, he realized that if Copernicus was right--that the Earth orbits the Sun--they could show it by observing the `parallactic motion' of the nearest stars. Incredibly, Galileo tried to use Alcor to see it but didn't have the necessary precision." If Galileo had been able to see change over time in Alcor's position, he would have had conclusive evidence that Copernicus was right. Parallactic motion is the way nearby stars appear to move in an annual, repeatable pattern relative to much more distant stars, simply because the observer on Earth is circling the Sun and seeing these stars from different places over the year. Alcor is a relatively young star twice the mass of the Sun. Stars this massive are relatively rare (less than a few percent of all stars), short-lived and bright. Alcor and its cousins in the Big Dipper formed from the same cloud of matter about 500 million years ago, something unusual for a constellation since most of these patterns in the sky are composed of unrelated stars. Alcor shares a position in the Big Dipper with another star, Mizar. In fact, both stars were used as a common test of eyesight among ancient people. One of Galileo's colleagues observed that Mizar is a double, the first binary system resolved by a telescope. Many years later, Mizar A and B were determined to be tightly orbiting binaries, altogether forming a quadruple system. Now Alcor, which is near the four stars of the Mizar system, also has a companion. In March, members of the team attached their coronagraph and adaptive optics to the 200-inch Hale Telescope at Palomar and pointed to Alcor. "Right away I spotted a faint point of light next to the star," says Neil Zimmerman, a Columbia grad student doing his Ph.D dissertation at the museum. "No one had reported this object before, and it was very close to Alcor, so...it was probably an unknown companion star." The team returned months later and reimaged the star, hoping to prove the two stars are companions by mapping the tiny movement of both in relation to very distant background stars as the Earth moves around the Sun--parallactic motion. If the proposed companion were a background star, it wouldn't move with Alcor. "We didn't have to wait a whole year to get the results," Oppenheimer recalls. "We went back 103 days later and found the companion had the same motion as Alcor. Our technique is powerful and much faster than the usual way of confirming that objects in the sky are physically related." The more typical method involves observing a pair of objects over much longer periods of time, even years, to demonstrate that the two move together. Alcor and its newly found companion are about 80 light-years away and orbit each other every 90 years or more. In one year, the pair moves in an ellipse on the sky about 0.08 arc seconds in width because of the Earth's orbit around the Sun. This amount of motion, 0.08 arc sec, is about 1, 000 times smaller than the eye can discern. A fraction of this motion was easily measured by the scientists. The team was also able to determine the color, brightness and even rough composition of Alcor B because the novel method of observation that the team uses records images at many colors simultaneously. The team determined that Alcor B is a common type of Mdwarf star or red dwarf that is about 250 times the mass of Jupiter, or roughly a quarter of the mass of our Sun. The companion is much smaller and cooler than Alcor A. "Red dwarfs aren't commonly reported around the brighter higher-mass type of star that Alcor is, but we believe they're fairly common," Oppenheimer says. The team plans to use parallactic motion again, hoping to check that other objects it finds, such as exoplanets, are truly bound to their host stars.
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Will We Outlast the Search for Other Civilizations?
By Frank Schmidt
If, by some remarkable chance, an alien society--or their descendant self-replicating robots--makes contact with us, what will they think of us? What might we think of them? They may seem vile, or more compromising and considerate. What of their philosophy or religion, liberally objective or an uncompromising medieval "burn at the stake" mentality? Think of an advanced civilization tens of thousands of light-years away in a far corner of our galaxy or from a nearby galaxy a few million light-years away. Assume it's analyzing us with equipment far beyond anything we can imagine. They would, in fact, be detecting our planet thousands of years in the past, possibly millions. They wouldn't hear our transmissions or see us in our current form. If they waited for our current time to reach them, they may have long since vanished. Likewise, if we had technology to detect distant civilizations, we'd be looking way into the past. The primary question is this: How long might we or other technological civilizations continue to exist, a critical factor for correspondence between alien societies? The universe is estimated to be 13.7 billion years old. Stars and planets have come and gone. Our solar system is a relative newcomer. Time and space are so vast, and with life on other worlds likely arising randomly, the probability of advanced groups coexisting seems very remote indeed. Take Earth. Our civilization has been around for a tiny moment in cosmic time. If you represent the age of Earth, some 4.5 billion years, as a 24-hour clock, the last minute before midnight would be 3 million years, the time since we started to walk primarily on two legs. And the period since the rise of technology would represent only about 1/10,000th of a second. If we keep doing what we've been doing, this means other spacefaring societies would have little time to detect us or we to detect them. What have we been doing? As time went on, we sacked, burned and killed our kind. We polluted land, air and water. We produced garbage until we can't find
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places to put it. We made weapons so powerful as to completely destroy the cities we built. And we continue to expand our numbers exponentially with little regard for our planet, or the welfare of other species. We're causing extinctions on a profound scale. Fred Hoyle once said, "The more advanced a society becomes the more it may lead to its own destruction." If we're typical of advanced civilizations, this may not bode well for communication across the cosmos. With our intelligence, shouldn't we take the high ground, to be kinder and more considerate to ourselves and other life? We claim to have morality. If so, we may have more then a fleeting existence. The future is in our hands. The big question is whether we will survive for more than the blink of an eye in cosmic time. Astronomers have been searching for extra-intelligent civilizations. We may be alone now. Maybe we've been searched for many times, and maybe we'll be listened for numerous times in the future, perhaps so long from now that we may have long since turned to stone. Let's take a more probable scenario for coexistence: a hypothetical stellar system having the rare fortune of two or more Earth-like terrestrial planets in or near the habitable area around a star. What are the chances of higher life forms developing on two of them at the same time? Take Earth as a possibly typical example for human development. For most of Earth's geological history, life was bacterial. Only much later did complex organisms come about, probably from random extreme environmental changes. What other sporadic rolls of the dice may have transpired to bring humans to the scene? Similar events as on Earth could occur on other terrestrial planets. Each planet, though, is unique, even relatively similar ones. Random geologic events would likely occur during vastly different time scales on these planets. So even if advanced societies would have evolved on more than one planet in this star system, coexistence would still seem improbable.


Review: Astronomical Influences on Life on Earth
By John Delaney
For the past decade, dangers from space have been the rage in movies, documentaries and books. Announcements from asteroid-seeking observatories and amateurs about the trajectories of near-Earth objects quickly become fodder for animators and doomsday speculators. But while asteroids, Tunguska events and gamma-ray bursts usually serve as attention grabbers for book authors (evidenced by the alarmist title of Phil Plait's recent "Death From the Skies"), the number of cosmic influences on the Earth--specifically on the history of life-include forces both extreme and subtle. Jeff Kanipe's "The Cosmic Connection: How Astronomical Events Impact Life on Earth" (Prometheus, $27.95), presents treatments of objects and forces that have guided, and occasionally threatened, life. His writing is brief and deep, no doubt honed from years as a science writer and an editor for Astronomy magazine. Kanipe begins at a glacial pace, appropriately, with the beginnings of glaciology as expounded by researchers such as Louis Agassiz, who discovered glaciers move and created the concept of the ice ages. The debate about what caused them to advance and recede soon included theories of astronomical factors influencing Earth's climate. Ultimately, it was the theories of Milutin Milankovitch, formulated in the early 20th Century and based on mathematical proofs, which eventually found favor with the scientific community. Milankovitch explained how factors of the Earth's shifting orbit, wobble and changing angle with respect to the Sun could potentially produce Ice Ages. In addition to a solid description of the Milankovitch Cycles and their soft-spoken creator, Kanipe carefully notes that many problems with the theories still obstruct their complete acceptance. The author devotes two chapters to the Sun. In "An Imperfect Sun," Kanipe examines several lines of evidence linking sunspots, solar output and events such as the Little Ice Age. He also cites the hardships and benefits of this cold period on human history, from the frozen waterways of New York Harbor and the Thames River, to the acoustically superior wood of Stradivarius violins (shorter summers begat evenly spaced growth rings in spruce trees, and fantastic wood instruments, the theory goes). In "A Temperamental Sun," Kanipe reveals our star for what it is, an occasionally dangerous body given to coronal mass ejections capable of knocking out power grids and disabling satellites. And ultimately, he warns, the Sun will work against life on Earth, with temperatures reaching 100 degrees Celsius in 1.2 billion years. "And you thought global warming was bad!" he quips. Exploding stars and the risk they pose to us form another chapter. In fact, sterilizing radiation from a "nearby" supernova has been suggested as the cause for massive events such as the Permo-Triassic Extinction. Are there any stars to be wary of today? Kanipe focuses on Eta Carinae, one of the Milky Way's largest stars. It's also a potential hypernova candidate, which could produce gamma rays lethal to any life-sustaining planets as far as 10,000 light-years away, some studies suggest; Eta Carinae is 7,600 light-years away. Kanipe's book is well-researched, and he has a knack for smoothly utilizing first-person accounts of locations relevant to the topic at hand. For the section on the search for intelligent life, Kanipe cleverly incorporates his visit to a sand pit in Horsell Common in the U. K., the former home of H.G. Wells and landing point of the alien invasion in "The War of the Worlds." He writes: "The notorious landing site of Wells' Martian vanguard force was neither deep nor sinister. It was a mudhole." Along with thorough descriptions of famous impacts and their aftermaths, such as the Chicxulub Crater and the late Cretaceous Period extinction event, Kanipe incorporates some worst-case hypothetical scenarios of large asteroids plunging into the Atlantic near North America. "New York City? Destroyed by tsunami. No survivors." How about Lincoln, Nebraska? "Ground shocks would awaken the Yellowstone volcano, the largest in North America, creating a catastrophic eruption that would spew forth lava, ash and a variety of gases including sulfur dioxide into the atmosphere...nuclear winter conditions in the Northern Hemisphere." Frightening? Yes, but for the disaster-movie director demanding both spectacle and scientific accuracy, it doesn't get any better.
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Briefs: Water-Rich Planet Found Close to Our Solar System
A rocky and water-rich planet, not much heftier than our own, has been discovered so close to our solar system that astronomers one day may be able to study its atmosphere. Although astronomers are pretty certain water exists, they don't know its state, with speculations ranging from liquid to ice to an exotic state called a superfluid. The planet, GJ 1214b, about 40 light-years away, orbits a red dwarf. It's the only known "SuperEarth" exoplanet--worlds that have masses between Earth and Neptune---with a confirmed atmosphere. The planet is about three times the size of Earth and about 6.5 times as massive. It's the second smallest planet discovered outside of our solar system. GJ 1214b is rare among known rocky exoplanets because it partially eclipses, or transits, its star as seen from Earth. This alignment allows astronomers to calculate the size and density of the planet, so it's believed it's likely a water world with a solid center. The planet has a thick surrounding atmosphere of hydrogen and helium. Normally, a planet at that distance from this particular type of star would be so hot that any water on its surface would be vapor. But scientists think the thick atmosphere creates a high-pressure environment that keeps surface water liquid. There are downsides to having such a thick atmosphere: First, the pressure is crushing, making life as we know it difficult. Second, the thick atmosphere blocks light from the feeble star from reaching the planet. GJ 1214b doesn't orbit within the star's habitable zone. The planet was discovered using a suite of small, ground-based telescopes. New evidence suggests the earliest, most massive black holes could have originated inside giant cocoonlike stars. This idea is at odds with the prevailing thinking that large black holes form by the clumping together of smaller black holes. New data indicate the behemoths likely formed in the middle of even larger supermassive stars that could have held tens of millions of times the mass of our Sun. The monster stars probably started forming within a few hundred million years after the Big Bang. When the cores of these giant stars burned all their hydrogen, they would have collapsed, forming dense black holes. Meanwhile outside gas layers of the stars remained as a shroud. Eventually, the black holes would have swallowed the remaining stellar matter within their reach, ballooning rapidly to staggering weights, new data suggest.
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Astronomers have taken the first direct image of a planet-like object orbiting a star much like our Sun. The newly identified object, GJ 758b, orbits a parent star about 50 light-years away, comparable in mass and temperature to the Sun. Scientists aren't sure if the object is a large planet or a brown dwarf. They estimate its mass at 10-40 times Jupiter's. Brown-dwarf companions to solar-type stars are extremely rare. The planet-like object is at least 29 times as far from its star as the Earth is from the Sun, or about the distance between the Sun and Neptune. The fact that such a large planet-like object might orbit at this location defies traditional thinking on how planets form. Astronomers think most large planets form either closer to or farther away from stars, but not where GJ 758 B is. Astronomers have long wondered which came first, a black hole or the galaxy around it. The leading theory says the two co-evolve, starting small and building over time. But colossal black holes may zap galaxies into existence from scratch, new observations suggest. Astronomers recently observed a peculiar large black hole that didn't belong to a surrounding galaxy as expected. Until now, scientists thought the galaxy was merely shrouded in dust. The black hole, HE0450-2958, is about 5 billion light-years away. Astronomers think the black hole is powering star formation in the nearby galaxy by spraying its jets of high-energy particles toward it. As time goes on, the neighboring galaxy will likely grow to encompass the black hole. Astronomers have spotted a new type of extremely bright cosmic explosion they think originates from an exceptionally massive star. Like all supernovas, the blast is thought to have marked the end of a star's life. But in this case, that star may have started out with 200 times the mass of the Sun. The supernova, SN2007bi, was observed in 2007 in a nearby dwarf galaxy. It was 50 to 100 times brighter than a typical supernova. After analyzing its signature, astronomers confirmed it matches theoretical predictions of a so-called pair-instability supernova. There were severe doubts that stars that massive could ever form. Now scientists seem very sure there was a star with 200 solar masses. In a pairinstability supernova, the star has neared the end of its life and exhausted its main supplies of hydrogen and helium, leaving it a core of mostly oxygen. In smaller stars, Continued on page 9


Briefs: Hubble Spies Possible Oldest, Most Distant Galaxy
Continued from page 8 the core continues to burn until eventually it is all iron, then collapses in a Type II supernova, leaving behind a remnant black hole or neutron star. But in the case of an extremely massive star, while its core is still made of oxygen, it releases photons that are so energetic, they create pairs of electrons and their anti-matter opposites, positrons. When the matter and antimatter meet, they annihilate each other. This reaction reduces the star's pressure, and it collapses, igniting the oxygen core in a runaway nuclear explosion that eats up the whole star. The discovery of this rare type of supernova suggests that a few stars actually can grow into such large behemoths -- which has long been a topic of debate. The revamped Hubble has spied what might be the oldest, most distant galaxy yet seen. The faintest and reddest objects in new Hubble images are galaxies that formed 600 million years after the theoretical Big Bang, which occurred 13.7 billion years ago. UK astronomers took images of galaxies in the early universe with Hubble's brand new Wide Field Camera 3, which can take highly sensitive measurements in the infrared. Infrared light is light invisible to the human eye, with wavelengths about twice as long as visible light. The new image includes the Hubble Ultra Deep Field. Another recent survey found 22 of the earliest galaxies to form in the universe. A recent Hubble image reveals the perfect dust laboratory in the sky and could help astronomers pin down the raw ingredients needed to give birth to baby stars. The photo is a composite of four images taken by Hubble's Advanced Camera for Surveys. The resulting closeup reveals the northwest region of the Iris Nebula, or NGC 7023. The nebula is a region of star formation that lies about 1,400 light-years away in Cepheus. The image shows billowing mounds of cosmic dust. Scientists were particularly interested in parts of the nebula that appeared redder than expected. Considered a reflection nebula, NGC 7023 scatters light from a massive nearby star, HD 200775, that's 10 times the Sun's mass. Typically, reflection nebulae appear blue, because dust grains scatter blue light more efficiently than red. Some hydrocarbon-based compound must be causing these dusty filaments to take on the red tinge. Astronomers also used Hubble's Near Infrared Camera and MultiObject Spectrometer to try to determine the chemical makeup of the nebula. The world's largest picture of the Milky Way, taken by Spitzer, was unveiled last month at the Adler Planetarium in Chicago. The new image covers an area 120 feet long, 3 feet tall at its sides and 6 feet tall in the middle, where the galaxy's central bulge is depicted. The panorama represents the effort of two Spitzer survey teams, who used two of the telescope's onboard instruments, the Infrared Array Camera and the Multiband Imaging Photometer. The image was made from stitching together 800,000 pictures taken by Spitzer, for a total of 2.5 billion infrared pixels. It covers about half of the entire galaxy and is the highest-resolution, most sensitive infrared picture of the Milky Way. Scientists have found evidence that magnetic fields are behind gamma-ray bursts. Theorists had predicted magnetic fields could explain how gamma-ray bursts produce jets of bright radiation that shoot into the universe. But no one observed the presence of a magnetic field in a gamma-ray burst until a year ago. On January 2, 2009, a gamma-ray burst erupted and was quickly detected. It was reported immediately to telescopes around the world, and one robotic scope automatically began observing it. The telescope was fitted with a filter that detects polarized light, or light electrically and magnetically aligned in a certain direction. The observatory found polarized light in the gamma-ray burst signature, which indicated the light originated in a magnetic field. Cassini cameras have captured images of a mysterious hexagon-shaped cloud formation likely formed by the path of a jet stream flowing around Saturn's north pole. The hexagon encircles Saturn with an estimated diameter wider than two Earths. The associated jet stream likely whips along the hexagon at 220 miles per hour. The last visible-light images of the hexagon were captured by Voyager nearly 30 years ago, the last time spring began on Saturn. For the next 15 years, the north pole was shrouded in winter darkness, which hid the hexagon from Cassini's visible-light cameras. During Continued on page 10
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Continued from page 9 this time, the craft's infrared instruments detected the shape using heat patterns, with resulting images showing the hexagon is nearly stationary and extends deep into the atmosphere. Saturn's eccentric orbit might be the cause of the uneven distribution of ethane and methane lakes on Titan. Cassini images reveal liquid methane and ethane lakes in Titan's northern high latitudes cover 20 times more area than lakes in the southern high latitudes. Data also show significantly more partially filled and nowempty lakes in the north. Why Titan shows these north-to -south differences isn't known. A possible explanation is related to eccentricity of the orbit of Saturn, and hence of Titan, around the Sun. In this configuration, the difference between evaporation and precipitation isn't equal in opposite seasons, which means there's a net transport of methane from south to north. Over scales of tens of thousands of years, Saturn's orbital parameters vary, at times causing Titan to be closer to the Sun during its northern summer and farther away in southern summers. This should produce a reverse in the net transport of methane and lead to a buildup of the methane and ethane, and an abundance of lakes, in the southern hemisphere. Astronomers have accurately measured the distance between Earth and a black hole for the first time. They determined V404 Cygni is 7,800 light-years away, slightly more than half the distance previously assumed. The measurement will enable scientists to better gauge how black holes evolve. They hope to determine whether there's a difference between black holes that evolve from the collapse of a star without a supernova and black holes that evolve via a supernova and a temporary intermediate star. The distance to V404 Cygni was determined by measuring radio emissions from the black hole and its associated dying star. Using radio telescopes, a team measured the parallax shift of the black-hole system. This involves measuring annual movement in the sky of the black-hole system as a consequence of Earth's orbit around the Sun. Previous overestimation of V404 Cygni's distance was due to underestimation of the absorption and diffraction of interstellar dust, which can give an error margin of about 50%. Error margin of the new measurement is under 6%. An orbiting X-ray observatory has found the larg10

est known reservoir of rare heavy metals in the universe. Chromium and manganese were detected from observing the central region of the Perseus cluster 225 million light -years away. The metallic atoms are part of the hot gas, or intergalactic medium, between 190 galaxies within the cluster. This is the first detection of chromium and manganese from intergalactic space. Supernovas forge these heavy elements and also create vast outflows called superwinds. These galactic gusts transport heavy elements into the intergalactic void.

Moche Guide in 7th Edition
"Astronomy: A Self-Teaching Guide" by AAA member Dinah Moche has gone into its seventh edition (Wiley, paper, $19.95). It's been completely revised and updated, with more than 100 new photos, including a full -color insert, and diagrams that clarify basic concepts without mathematics. Website addresses throughout link to astronomy resources online. Designed to make astronomy accessible and fun for general readers, the guide includes material on life in space. An interactive format with learning objectives, reviews, self-tests and answers help readers learn fast. The book can be used on its own as a self-teaching guide, a supplement to astronomy course materials or as a handy reference.

High Line continued from page 2 One of the Astroscans pointed at the Pleiades and showed a spectacular view of that cluster, revealing more than 20 stars. Many people showed up despite cool, windy weather. A cloudbank hovered to the east, but didn't obscure the sky until after we left. This was the last meeting at the High Line for the season, so unfortunately we didn't see Mars. I had to go home to the Bronx to view Mars in my 60mm refractor as it cleared the trees to my east at 11 p. m. on November 28. Syrtis Major, a dusky gray triangular area, was visible on the coral pink Martian disk in the 60mm refractor at 100x. Hopefully we'll have opportunities to see Mars at other observing sessions at other sites in 2010.


Events on the Horizon January 2010
M: members; 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, January 2, 9, 16, 23, 30 8:30-10:30 p. m Observing, Inwood Hill Park, Manhattan, P, T, C Next dates: Saturdays in February. Friday, January 8, 6:15 p. m. AAA lecture, FREE, P Jerry T. Bonnell, scientist at NASA's Goddard Space Flight Center and co-founder of the Astronomy Picture of the Day website, will present "Skyscapes in 2008" in the Kaufmann Theater of the AMNH. Monday, January 11, 7:30 p. m. Hayden Planetarium lecture, P, AMNH In "The Medea Hypothesis," paleontologist Peter Ward proposes a vision of life's relationship with the biosphere, one that has frightening implications, yet offers hope. He argues that life might be its own worst enemy Thursday, January 14, 6:30-8:30 p. m. Recent Advances in Astronomy Seminar, M, HQ Pre-meeting dinner at 5:15 at the Gee Whiz Diner, Warren and Greenwich streets. Next date: February 11. Thursday, January 21, 6:30-8 p.m. Observing, Charles Dana Discovery Center P, T, C A short discussion of the winter sky followed by observing. The center is at 110th Street and Lenox Avenue. Tuesday, January 26, 6:30-8:30 p. m. Observers' Group, M, HQ Pre-meeting dinner at 5:15 at the Gee Whiz Diner, Warren and Greenwich streets. Next date: February 23. Saturday, January 30, 10-noon Solar Observing, Central Park, P, T, C At the Conservatory Waters. Next date: February 27.

Planetary Images, Holst's `The Planets' To Merge at Houston Symphony Concert
Music and science will merge at a Houston Symphony concert Thursday, January 28 when a film featuring the latest high-definition planetary images will be shown on a 24-foot screen above the stage during a performance of Gustav Holst's orchestral suite "The Planets." The concert, at 8 p. m. at Carnegie Hall's Stern Auditorium/Perelman Stage, will be led by music director Hans Graf. For the program, "The Planets--An HD Odyssey," the symphony collaborated with NASA, the Jet Propulsion Laboratory and producer/director Dr. Duncan Copp. Holst's suite contains seven movements attributed to each planet except Earth; Jupiter is the best known. Copp and his team worked with images from missions such as the Mars rover explorations, Cassini-Huygens, Voyager 1 and 2, Mariner 10, Magellan, Messenger and Galileo. The orchestra will also perform works by Stravinsky and Dutilleux. A pre-concert talk at 7 will feature Thomas Cabaniss, composer and faculty member at The Juilliard School. Info: carnegiehall.org or 212-247-7800.
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Contacting the AAA
If you want to have a question or @aaa.org, or leave visit us on the web join, volunteer, participate in events, change your address, e-mail members a message at: (212) 535-2922. Also, at www.aaa.org.


Dark Energy continued from page 1 sands of years of looking at the sky, the universe has appeared static. But today, telescopes describe something different and allow new questions to be asked. "Is the universe infinite? What is its future? What is it made of? How big is it?" Baltay asked. Almost all the universe is dark energy and dark matter, 72% and 27%, respectively. Although we don't know what either of those forms of energy is, their natures determine much of the universe's future dynamics. Physics has so far addressed only about 1% of the universe through visible matter--the stuff we're made of, elements of the periodic table and their quark foundations. Knowing only 1%, however, doesn't mean we're not in a golden age of cosmology, Baltay noted. We know a lot about the universe. It appears to be about 10 billion20 billion years old. It's lumpy locally and very smooth, on the largest scales, in all directions. Just look at the galaxies of stars nearby and then at the ancient cosmic background radiation light formed in the universe's infancy. It appears to be in a state of expansion, an aftermath of the Big Bang. Confidence in measurements of

the Hubble's constant has grown over many years and across careers of young and old scientists. Dark matter hopefully will be revealed by the Large Hadron Collider. Dark energy now seems to be unlike anything known, but general relativity provides testable predictions: The acceleration should be a deceleration at an earlier time. Therefore, stick with Type Ia supernova to delve into the dynamics of dark matter, Baltay asserted. The Palomar-Quest (PQ) Survey spearheads measurements of nearby supernovae beginning this year to better measure their intrinsic brightness and thereby calibrate the nearby portion of the Hubble diagram, which demonstrates the expansion. Using the Oshin Schmidt Telescope with a 1.2 meter mirror and a 10-square-degree detector comprised of 112 CCDs, objects are found by image subtraction across nights. More than 85% of the objects found are asteroids. Incidentally, astronomers also discovered Sedna, Orcus and Quaoar, in the Kuiper Belt, which played major roles in the International Astronomical Union's redefining the word planet. Oddly, none of the team's supernova work received nearly as much press.

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