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Journal of the Amateur Astronomers Association of New York February 2008 Volume 56 Number 2, ISSN 0146-7662

EYEPIECE

Will Dark Energy Become Less Mysterious?
By Lynn Darsh
Although cosmologists know little a b ou t d a r k energy, even though it takes up 70% of the expanding universe, that may change in the next 10 years.
That was a central point in a December 11 Hayden lecture by Dr. Adam Riess, professor of astronomy and physics at Johns Hopkins and a scientist at the Space Telescope and Science Institute, who actively uses the Hubble Space Telescope. He noted that dark energy has excited the interest of NASA, the Department of Energy and the European Space Agency because it lies at the crossroads of quantum mechanics and general relativity. The National Academy of Sciences has endorsed further evaluation of three concepts for Joint Dark Energy Missions for a possible new "Hubble-class" space telescope, Riess observed. The goal, he said, would be "to measure if dark energy is evolving and changing its strength...and if general relativity remains a valid description of the universe on the largest scales." Riess said the two great pillars of m od er n p h ysics are quantum mechanics, the rule book for the small scale, and general relativity, the rule book for the large scale. Until now, these sets of rules haven't been linked. He believes exploration of dark energy is central to a study of quantum mechanics, general relativity and string theory, and is likely to lead to "something interesting." "Understanding dark energy lies in the critical path to understanding gravity, and the fate and the origin of the universe." Meanwhile, Riess stated, "we still have the Hubble and the astronauts are due to visit Hubble during August where they will install two new instruments, repair two other ones, and add a complement of batteries and gyro-

scopes to bringing it to tip-top shape, the best it's ever been...and if this happens successfully this will allow us to continue our studies of dark energy with Hubble."
Riess noted that future research in t o d a r k en er gy will be carried out using not only ground-based telescopes and the refurbished Hubble, but possibly a new "Hubble-class" space telescope, planned for multinational Joint Dark Energy Missions. Discussing "Dark Energy and the Accelerating Universe," Riess said discovery of the accelerating universe will be viewed as the beginning of a new search for answers to fundamental questions about the fate, history and composition of the universe and the rules that shape its development. As principal investigator of the "High-z Team" formed to "measure the cosmic deceleration of the universe with Type Ia supernovae," Riess was the first person to use observational data to calculate a non-zero value for Einstein's cosmological constant. The results showed that something was causing the expansion of the universe to speed up during the last 7 billion years. This was the first evidence for the existence of dark energy. Riess described how, using the Hubble t o st u d y an additional 25 supernovae with redshifts greater than 1, scientists checked that Type Ia supernovae didn't appear fainter than expected due to factors such as the presence of dust or an intrinsic difference in brightness of supernovae formed in the early universe. Since the original Type Ia supernovae study was made public in 1998, a number of research findings have confirmed the existence of dark energy. Consensus

Dark Energy continued on page 14


What's Up
By Tony Hoffman The Sky for February 2008
Lunar Eclipse, I d on 't know if there's a perfect lunar eclipse, but the one that occurs on the night of February 20 will do until a real one comes along. Unlike last March's total lunar eclipse, which was already in progress as the sky darkened, and last August's, which was interrupted by dawn, this one happens in mid-evening for observers in the East. The Moon is also 10 degrees north of the celestial equator, so it's relatively high in the sky. It will be more than 30 degrees high in the East when the partial phase begins at 8:43 p.m. Totality starts at 10:01 p.m., reaches midpoint at 10:30 and ends at 10:52. This eclipse has a treat: The Moon lies between two bright orbs: Regulus, 3 degrees above the Moon, and Saturn, 4 degrees to the Moon's lower left. Annular Solar Eclipse. O n F eb r u a r y 7, t h er e will be an annular solar eclipse. The Earth is near its closest to the Sun, and the Moon, ranging outward in its orbit around Earth, is far enough away from us that the Moon's disk doesn't completely cover the Sun. Because of this, a little bit of sunlight shows as a bright ring around the dark disk of the Moon. This phenomenon, however, happens in Antarctica. Observers in Australia and New Zealand will see a partial eclipse. Planetary Fun. J u st t h r ee n igh t s a ft er it h elp s frame the Moon during the eclipse, Saturn reaches opposition. It's closest to Earth, at its brightest, and visible all night. Its rings are beginning to close, but they will give a nice view, revealing more of the planet's disk as they become thinner. Saturn's rings can be easily seen in even the smallest telescope. Meanwhile, Mars starts the month shining at magnitude -0.6, poised between the tips of the horns of Taurus. Observe it while you can; by month's end its disk will have shrunk to less than 10 arc-seconds in diameter, the minimum size for getting good views of its elusive surface in a small telescope. Mars will cross into Gemini late in the month. Morning skywatchers will h a ve a gr a n d view of the close conjunction of Venus and Jupiter February 1. Before dawn these worlds will stand barely half a degree apart, a bit greater than the diameter of the Full Moon.
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The Moon undergoes a total eclipse on February 20, when it's sandwiched between Saturn and Regulus. February 1 Venus lies half a degree from Jupiter; Moon lies near Antares. February 4 Moon passes Jupiter and Venus. February 6 New Moon at 10:44 p.m. February 7 Annular solar eclipse. February 13 Moon at perigee, 230,043 miles from Earth, 7:56 p.m.; first-quarter Moon at 10:33 p.m. February 16 Moon passes Mars and Beta Tauri. February 20 Moon passes Regulus; Full Moon at 10:30 p.m.; total lunar eclipse. February 21 Moon passes Saturn. February 24 Saturn at opposition, 5 a.m. February 28 Last-quarter Moon at 9:18 p.m.; Moon passes Antares.

Mars: A Challenge to Observe
By Joseph A. Fedrick
Frequently cloudy skies continued to hamper viewing of Mars this year. Even when skies were clear, poor turbulent viewing hindered viewing, and smeared out and distorted views of Mars. Others, including Tony Hoffman and Tom Haeberle, have found viewing Mars difficult this year. Apparently the proximity of the jet stream has produced constant storms and turbulent air. I managed to view a large dusky triangular area on Mars, Syrtis Major, on December 17 around 7 p. m. and on December 24 around 11 p. m, as it crossed Mars' meridian. I was using my 60mm, f/15 refractor at 100x. A view of Mars on December 15 around 9 p. m. revealed Fedrick continued on page 13


A Message from AAA President Richard Rosenberg
Hello, members: February begins with a special planetary event. At dawn on February 1 Venus and Jupiter, the two brightest planets, will be less than a degree apart! Look for them blazing in the southeast. Naked eyes are all you will need, although binoculars will improve the view. However, the big event this month is a lunar eclipse the evening of February 20. Like last year, we 'll gather at Carl Schurz Park in Manhattan. Head east on 86th Street as far as you can go. The Moon will be in Leo as it was last March, but will be picturesquely placed between the bright star Regulus and the ringed planet Saturn. Watch the Moon move away from Regulus and toward Saturn during the evening. The action begins with a partial eclipse starting at 8:43 p. m. Total eclipse starts at 10 and lasts for 52 minutes, followed by another partial eclipse which ends at 12:09 a. m. Join us for one of the fun events of the year. We'll return to Riverside Park on Saturday, May 10. In conjunction with the Riverside Park Fund, we 'll meet at West 96th Street and the Hudson River. The location right at the river's edge is gorgeous and dark (by NYC standards). A crescent Moon, Mars, Saturn and even Mercury will be available for viewing. As of mid-January, two-thirds of for your support. Soon we'll send you us a donation, additional thanks; we'll n't renewed yet, we hope to hear from our membership have already renewed. If you're among that group, thank you (and new club members) our brochure and a membership card. If you've given include a letter allowing you to deduct the amount from your taxes. If you haveyou soon.

Rich Rosenberg, AAA President, pr esident @a a a .or g, (718) 522-5014

MIT Prof Will Address AAA Feb. 1 on Gravitational Waves
Nergis Mavalvala, a ssocia t e p r ofessor of p h ysics, and Cecil and Ida Green career development professor at MIT, will address the AAA Friday, February 1 on "Detecting Gravitational Waves: LIGO and the Search for the Elusive Wave." The free public lecture is at 6:15 p. m. in the Kaufmann Theater of the AMNH. Mavalvala will begin with an introduction to gravitational waves: what they are, what kinds of sources emit them and how we might measure them. She will then take a virtual tour of the Laser Interferometer Gravitational-wave Observatory (LIGO) and describe key ingredients to make a sensitive gravitational-wave detector. Then she'll take a look at what we can learn about the universe using recent results from operational gravitational wave detectors. "Gravitational waves a r e b elieved t o b e em it t ed by massive objects in space, and can carry very different information about their source than light waves," Mavalvala notes. "In some cases, gravitational waves may be the only `messenger' to reach us from the source. Studying gravitational waves and light from an object such as a neutron star or black hole is analogous to learning about it using both sight and sound; we form a much richer picture than with sight only." A graduate of Wellesley College with a degree in physics and astronomy and holder of a Ph.D. in physics from MIT, Mavalvala did her doctoral work with Prof. Rainer Weiss, one of the founding fathers of LIGO and the worldwide effort to detect gravitational waves using laser interferometers. She has worked on gravitational Lecture continued on page 7
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Amateurs Play Increased Role in Astrophotography
By Katherine Avakian
Amateur astronomers have become so a d ep t a t astrophotography that about half of the images on the Astronomy Picture of the Day (APOD) website last year were from amateurs, Dr. Jerry T. Bonnell, co-founder of the site, told an AAA lecture audience January 4. Bonnell's talk, viewing of some of Bonnell, a scientist also noted that digit increased quality of "Skyscapes in 2007," accompanied a last year's best images from the site. at the Goddard Space Flight Center, al astrophotography has underpinned astronomy photos. A 20-frame mosaic measuring 12 degrees across showed the northern part of Cygnus. Bright red emission clouds could be seen throughout this "very complex image" as well as the dark Northern Coal Sack Nebula and numerous other nebulae and star clusters. The brilliant supergiant Deneb, Cygnus' alpha star, forms the top of the Northern Cross and is also a part of the Summer Triangle. Bonnell noted dark matter in the constellation is not detectable on any wavelength. Saturn's moon Iapetus wa s a p ict u r e in con trasts: "one really bright side and one really dark side." It looks as if some dark material was thrown onto its surface and scattered. Website information on this material says, "Infrared spectra indicate that it possibly contains some dark form of carbon...."Whether Iapetus' colors are the result of unusual episodes of internal volcanism or external splattering remains unknown." The moon also shows a 450-kilometer impact crater on top of an older crater. A picture showing space shuttle Atlantis docked at the ISS was taken by two amateur astronomers. The shuttle had delivered a set of 250-foot solar arrays which were installed on the space station. Subsequently, as Atlantis pulled away to return to Earth, its crew took a picture of the space station with its array of solar panels in place. The ISS can be viewed as it streaks across the sky if you know its transit time, Bonnell noted. After two years exploring M a r s' surface, the Opportunity rover arrived at Victoria Crater. The 750-meter impact crater is the largest yet visited. Bonnell showed an orbital view of the crater. Another image showed Victoria's expansive terrain with Opportunity perched on its rim, waiting for instructions on taking a safe path down its steep 70-meter slope. APOD began in 1995 and has been run since by Bonnell and Robert Nemiroff, a professor at Michigan Technological University. Its archive contains the largest collection of annotated astronomical images on the Internet. The website receives half a million hits a day and is translated into 16 languages. APOD is at http://

A magnitude -2 image of Comet McNaught arcing across the Australian sky just after sunset was taken by its discoverer, Robert McNaught. The brilliant comet's 150-million kilometer tail showed striations throughout, and Bonnell noted its three-dimensional aspect projected against the darkening sky. Visible in 2006, the comet reached perihelion in early 2007, coming within the orbit of Mercury. Thereafter it dimmed as it moved into the solar system. Bonnell explained the structure of the tail by saying, "Solar radiant pressure, the pressure of sunlight, actually drives the dust away from the nucleus... Particles of different sizes coming off the nucleus account for the structure of the tail." A wide-angle image of C a lifor n ia 's Death Valley at night showed a sky filled with stars. Bonnell said it's "one of the darkest skies in the continental United States." Another nightscape pictured the Alborz Mountains in northern Iran illuminated by a first-quarter moon. Overhead, Orion and Canis Major stood out among a multitude of stars. This picture was taken by a member of The World at Night, an organization of astronomers around the world who specialize in landscapes. Their goal is to "share and enjoy the world's sky at night." Two views of the Pleiades revealed different aspects of dust in its system. The image in visible light showed dust reflecting the starlight of its hot blue stars. The infrared image, by Spitzer, shows the dust to be glowing in the cluster. "Dust scatters blue light very efficiently and transmits red light," Bonnell said. These very fine dust particles are what's left over from formation of the stars.
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The Largest Binoculars in the World!
By Edward J. Fox
At 10,500 feet a t t h e M ou n t G r a h a m I n t er n a tional Observatory in southeastern Arizona, the largest binoculars in the world are nearing completion. The Large Binocular Telescope (LBT), built for $120 million by an international consortium, is the first of a new generation of extremely large telescopes. It will be the world's most powerful telescope until a bigger, better telescope is built somewhere else. lar to a gun turret on a battleship. Weighing 600 tons, the instrument floats on a film of oil pumped to a pressure of 1,800 psi and uses four 3-horsepower motors on each axis and a balance system which shifts water in and out of counter-weight ballast tanks to balance the telescope. When one of the two p r im a r y m ir r or s is t ilt ed , there are slight but measurable changes in its shape. Various controls are programmed to restore the shape. Likewise, the effects of temperature are monitored to keep the mirror as close to ambient temperature as possible, by ventilating a honeycomb pattern on the back. Temperature specifications require a gradient of less than 0.1 degree C. across the entire surface of the mirror. The adaptive-optics system relies on a central element, a very thin deformable mirror, which can modify the incoming light pattern to remove variations in the waves caused by the atmosphere. The corrective mirror changes shape about 1,000 times a second through the control of 672 magnets glued to its back. The resultant light waves are restored to near-perfect focus. The LBT is designed with real-time computing technology to maximize pointing precision and image stability. Dr. John Little, LBT lead engineer, states, "With digital feeding, the mirrors can be positioned to resolve one-thousandth of an arc-second, or roughly a BB at 32 and one-half miles." The LBT will have two pairs of wide-field spectrographs, one for optical, the other for the near infrared. A key use of the LBT will b e wit h in t er fer om et er s that combine the signals from the two telescopes, almost as if they were coming from a single telescope. Using this principle, waves with the same phase of the same amplitudes can be combined or those with opposite phase can cancel each other. In the former case, light beams can be combined to coherence for a genuine field of view, giving the LBT a resolution 10 times greater than the Hubble. It's thought the LBT will image remnant disks of gas and dust in the vicinity of newly formed solar systems and detect gaps
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The LBT relies on two 27.6-foot primary mirrors and will have a light-collecting area equivalent to a 39foot circular aperture. Combined light beams from the two primary mirrors will give the resolution of a 75-foot telescope. The completed telescope will have a resolution unmatched anywhere, even by the Hubble.
The complete complement of instrumentation won't be operational until 2009. But the first of the two telescopes, the left, achieved "first light" in October 2005. Each mirror was built in a fa cilit y u n d er t h e University of Arizona football stadium, where a furnace heated 20 tons of glass, spinning them into a parabolic shape at 2,130 degrees. It was then annealed by gradually reducing the heat of the furnace The process took three months. Each mirror was then polished to an accuracy of 3,000 times thinner than a human hair. No point across the surface of the mirror varies from the desired shape by more than 25 nanometers--a millionth of an inch. The mirrors are designed be used in tandem or individually. For example, optical images can be captured by both, or an optical image by one at precisely the same time an infrared image is collected by the other. The observatory building's t op 10 st or ies a r e rotated independently of the telescope, but in synchronization with it, to within +/- 1.5 degrees. To achieve the required stiffness, in wind conditions up to 50 mph, the base of the structure is a massive concrete pier 66 feet or 11 stories high and 46 feet in diameter, on mountain bedrock. The telescope is of an altitude-azimuth design, simi-


Alien Life Forms May Not Fit Into Our Way of Thinking
By Katherine Avakian
"We are alone in the universe or we a r e n ot . Bot h possibilities are equally profound and equally exciting," said Chris Impey, distinguished professor and deputy head of the astronomy department at the University of Arizona, in his December 3 AMNH lecture and book, "The Living Cosmos" (Random House, $27.95). He said its subject, astrobiology, was speculative due to its "almost complete absence of data." Yet his talk was mind-opening about life on Earth and its possibilities elsewhere, perhaps in form and function so unusual as to be unrecognizable. Biology may be common to the universe because organic molecules form easily and naturally, Impey noted. There's evidence life formed early in Earth's history, and organisms can survive in such extreme environments as pure acid or deep on the ocean floor at temperatures of 700 degrees and pressures of 700 atmospheres. He said the cosmic cycle is tied to recycling of elements "forged in the cauldrons in the centers of massive stars" and flung into interstellar space upon their violent deaths. "If stars were selfish and hoarded their cauldrons, there would be no life in the universe. Every star would be a tomb, keeping its heavy elements inside." Life on Earth has existed wit h in cer t a in p a r a m eters. For 85% of its history, life was microscopic, and Earth remains "overwhelmingly microbial. It is a microbial planet." Although life formed easily, it was selective and developed into diverse evolutionary niches. Impey said most species become extinct, and intelligence on Earth is rare. "Evolution is not deterministic, and many random influences will play out differently," Impey said. He noted that 25 million years ago, whales and dolphins experienced a surge in brain growth, which then stabilized and was overtaken by the brain mass of humans and apes. But if whales and dolphins should undergo another evolutionary surge, they'd probably surpass humans. Impey pointed out different forms intelligence can take. He said the brain of an octopus is a descriptive one,
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and its architecture completely different from ours. Its skin is its brain, built like a network computer with several billion receptors which can change color and texture 10 times a second, providing camouflage and protection from predators. More than 250 extrasolar planets a r e k n own , and the Milky Way is thought to harbor 1 billion habitable worlds. Criteria for habitability are the presence of elements including the carbon atom, which is the basis for life as we know it, water and the amount of warmth from the parent star. Impey acknowledged the difficulty of detecting life on extrasolar planets, but said in 10-20 years, the Terrestrial Planet Finder and other NASA missions will detect the atmospheres of exoplanets and look for modifications by temperature, oxygen and ozone, water vapor and other molecules which might reveal traces of life. But he warned that alien life forms and intelligence may not fit neatly into our anthropomorphic way of thinking. Life elsewhere might manifest itself as noncellular, without a containing membrane for genetic material. There could also be gene swapping, or organism swapping, "exchanging genetic material at a much higher level." Or the genetic material can operate on a planetwide scale, "essentially using geo-engineering as its way of making use of energy." Impey said all this may sound like science fiction, but its rudiments lie in the biology we know. However, Impey spelled out a st a r t lin g scen a r io. While noting our technological advances in computer capabilities, which can create video games and increasingly sophisticated artificial realities, he spoke about an idea from philosophers called "simulation hypothesis." It claims a highly advanced civilization could easily create simulated creatures like us on a planet-wide scale, and could "create the entire history of the thought processes of human civilization, and we wouldn't know the difference." It's certainly unsettling to think you might exist only within the computerized reality of an alien entity.


Our Intrepid Member's100 SOHO Comets--and Counting
By Tony Hoffman
On December 10, a ft er m or e t h a n six yea r s of searching images taken by the SOHO (Solar and Heliospheric Observatory) spacecraft, I found my 100th SOHO comet. It was faint yet distinct as seen by SOHO's wide-field LASCO C3 camera, and brighter in the narrow-field C2 images. (LASCO instruments create an artificial solar eclipse to reveal the Sun's corona, as well as any stars, planets or comets in the vicinity.) It quickly faded as it approached the Sun and was vaporized, the fate of all Kreutz sungrazing comets found in SOHO's images. I first heard about SOHO comets with the finding of 1998 J1 (SOHO), the only comet discovered in LASCO images be easily visible in the night sky. When in 1999 Terry Lovejoy, an amateur, found two comets in SOHO's online images, I was intrigued. I'd been fascinated by sungrazing comets since reading a N ational Geographic a r ticle a bout 1965's Comet Ikeya-Seki, which was easily seen without optical aid in broad daylight when near the Sun. The computer I had in 1999 wasn't up to the task of hunting for SOHO comets. I'd make do by hiding the Sun behind a building on clear days and looking in its vicinity in the insane hope that a sungrazer would be visible to my unaided eyes. In June 2001, a r m ed wit h a n ew com p u t er , I b egan my search for Ikeya-Seki's tiny brethren in SOHO's images. Based on the prodigious totals some SOHO hunters were racking up (Michael Oates had found more than 130) and my experience as an observer, I figured I could find one in short order, and 100 wouldn't be out of reach. I soon found it was harder than it seemed. The tricky thing is to learn to spot the comets quickly enough to report them before other hunters. Competition is intense, and includes many skilled observers, three of whom have discovered comets in the night sky that bear their names. (SOHO comets are named for the spacecraft rather than the people who find them, who get their names on the discovery bulletin instead.). It took me seven months to find my first. By the end of 2002, I'd found two more, and by late 2003, after 2-1/2 years of hunting, my count was up to 10. In 2004, all my practice and hard work really bore fruit, as I led all SOHO hunters with 33 finds. Since then, I've averaged about 20 comets a year. I figured when I reached 100, I'd greatly curtail my efforts. Two days later, though, I was lucky to find one of the year's brightest comets. With no pressure to reach a milestone, I can monitor the Sun's vicinity at leisure. As Forrest Gump would say, "You never know what you're gonna get."

SOHO has revealed a n u n seen r ea lm of m a ssive solar storms releasing high-energy plasmas through which comets move, subjected to intense heat and tidal forces. Three new comet groups have been found in SOHO images, and SOHO's trove of tiny comets has helped scientists understand cometary fragmentation and the evolution of the Kreutz comet group (to which the great daylight sungrazers such as Ikeya-Seki, as well as more than 1,000 comets found in SOHO, belong).
I'm grateful that I could participate in this hunt, and that SOHO makes its images available online. I still find it amazing that I can sit in my Queens apartment and peruse near-real-time images of the Sun's vicinity taken from a spacecraft, even when it's night on the East Coast. To add to that surreal touch, I found my most recent SOHO comet (No. 103) during an ice storm. Lecture continued from page 3 waves ever since. After receiving her doctorate, Mavalvala was a post-doc at Caltech, during which she worked directly on LIGO detectors as they were being constructed and made to work with high sensitivity. She joined the physics faculty at MIT in 2002. The 2007-08 AAA lecture series fea t u r es t h ese other speakers: March 7: E r ic G ot t h elf, C olu m b ia Un iver sit y, "Juvenile Neutron Stars and their Outbursts"; April 11: Eric Myers, LIGO Hanford Observatory, "Searching for Ripples in Space-Time with your Home Computer"; May 2: Ar lin C r ot t s, C olu m b ia Un iver sit y, "Liquid Mirror Telescopes Are Looking Up."
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Review:
By Terrell Kent Holmes
Michael J. Neufeld, chairman of the space history division at the Smithsonian's National Air & Space Museum, has written an excellent and engrossing biography of Wernher von Braun, one of the most important, controversial and divisive men in the history of science. "Von Braun: Dreamer of Space, Engineer of War" (Alfred A. Knopf, $35) explores what sacrifices are acceptable, moral or otherwise, for the greater good of scientific and human advancement. Von Braun (1912-1977) grew up at the dawn of the space age in Germany. As an engineering student, he cultivated the single-minded drive, intelligence and charisma that would serve him throughout his life. Von Braun worked for the German Army to build liquid-fuel rockets that would become the dreaded V-2. His work in rocket engineering helped him rise within the Nazi military hierarchy, where he attained the rank of captain. Hitler made development of the V-2 rocket a top priority for the war, thus rushing von Braun and his team into unrealistic production quotas. This led to construction of the V-2 by POWs in concentration camps. Prisoners performing slave labor in the tunnels at Mittelwark were tortured and literally worked to death because of Hitler's production demands. The V-2 was finally fired at London and other European cities in September, 1944, wreaking havoc in the final months of World War II. Soon thereafter, von Braun was detained for allegedly making treasonous remarks. He narrowly escaped the concentration camps and eventually surrendered to the U.S. Army. He sought to fulfill his dream of space exploration in America, and tried to downplay the influence or reach the Nazi Party had on him and his project, denying any direct complicity in atrocities in Mittlewerk. Initially the move to America wasn't as fruitful as von Braun had hoped. That changed in 1952, von Braun's watershed year. Through speeches, magazine articles and television appearances, he inflamed the American public's imagination about space exploration. Von Braun became a celebrity overnight due to his charm, intelligence, enthusiasm and handsomeness. This burst of popularity brought his war history to light, and
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although questions about his Nazi past always faded away, he wasn't spared from other forms of harsh scrutiny. Comedian Mort Sahl remarked that the fawning 1960 von Braun biopic "I Aim at the Stars" should have been subtitled "But I Sometimes Hit London." The launch of Sputnik in 1957 alarmed America into accelerating its participation in the arms and space races. With the Kennedy Administration, von Braun's lifelong dream of putting a man on the Moon became a priority, and he and others raced to meet JFK's end-ofdecade deadline. Ironically, the 1969 Moon landing marked the end of von Braun's influence. Once the Moon was conquered, the space program became a decreasing priority. Von Braun eventually left the space program for the private sector, after helping lead NASA to a summit that seemed unreachable a few years before. Neufeld's dissatisfaction with previous biographies of von Braun inspired him to want to write the definitive work. His research is impressive, and while the many technical explanations of rocket technology are sometimes overwhelming, they don't hinder the book's readability; anything less would have been a disservice to both subject and reader. Moreover, Neufeld's thoroughness allows for reasonable speculation on events where evidence is scant or nonexistent. Neufeld weaves the Faust legend throughout the book to the point where it's almost a secondary subject, from the perfect opening epigram on a castle on a hill, a framed quotation on a wall, an article in L ook magazine. But the moral dilemma von Braun faced is the central theme. The moments where Neufeld tries to understand the context of von Braun's Nazi participation are often tempered by his censure of von Braun's lies, convenient half-truths and self-aggrandizing lack of conscience. Wernher von Braun was a visionary who gained his reputation and notoriety as a brilliant scientist. He also helped drive the mechanism of one of the most grotesque killing machines in human history. He earned that status in the darkness, changing the world while casting his Faustian shadow out toward the stars and down into the cauldron of genocide.


As Usual, AAS Annual Meeting Produces a Pile of News
Highlights from the annual meeting of the American Astronomical Society last month in Austin, Texas: Supermassive black holes spin a t sp eed s a p proaching the speed of light. Nine huge galaxies were found to contain furiously whirling black holes that pump out jets of gas. The overall effect makes gas spiral in toward the black hole and creates a magnetic field that shoots inflowing gas back out as a jet. Jets may drive the rotation of central black holes in galaxies. Observed jet power and accretion rates were huge: One black hole ate 10 Earth masses per month and, from its surroundings, spat out 50 times the Sun's annual energy per second. Our galaxy could be full of r ogu e b la ck h oles that devour anything that crosses their paths, computer simulations suggest. When black holes merge, energy produced may kick the newly merged black hole--a rogue black hole--out of its galaxy. Some mergers would also create gravitational waves, which could hurl the merged black hole up to 2,485 miles per second. Even if every globular cluster in our galaxy started out with an intermediate-sized black hole, only 30% would hold onto them through a merger. Astronomers have spotted sm a ll ga la xies n ea r the beginning of time that resemble ancestors of the Milky Way. They're one-tenth to one-twentieth the size of the Milky Way, with 40 times fewer stars. Light from ancient clusters was emitted 2 billion years after the Big Bang, the best evidence of precursors to larger, spiral structures. Bigger early-universe galaxies evolved into elliptical galaxies. A half-dozen hefty black holes h id e ou t wh er e they're least expected, in skinny galaxies, implying galaxies don't need bulges to harbor monstrous black holes. New observations show galactic obesity isn't the only path to black-hole generation. Dark matter might play a role in early development of supermassive black holes. Astronomers have turned up six supermassive black holes in thin galaxies with minimal bulges. Brilliant blue blobs weigh in g t en s of t h ou sa n d s of solar masses have been found in intergalactic space. They seem to be star clusters born in a galactic smashup 200 million years ago. The clusters are along a wispy bridge of gas between three colliding galaxies--M81, M82 and NGC 3077--12 million light-years away in Ursa Major. Many of the clusters' stars are an estimated 10 million years and younger. A moth-like structure wit h a 22-billion-mile wingspan is a massive dust disk surrounding a nearby, young star. Such disks are typically flat structures where planets can form. This shape, 100 light-years away, comes from starlight scattering off the dust. HD 61005 is apparently plowing through higher-density gas, causing material within its disk to be swept behind the star. A colossal cloud of ga s is r a cin g t owa r d a collision with our galaxy. The crash, in 20 million-40 million years, could trigger an intense burst of star formation. The cloud is 8,000 light-years from our galaxy's disk. Packed with enough hydrogen to make a million stars like the Sun, it's 11,000 light-years long and 2,500 lightyears wide. The cloud will likely strike a region farther from the galactic center than our solar system. A quartet of stars h a s b een d iscover ed swir lin g around each other. A gaseous disk might have pushed the stars into their tight orbits. The rare group is 166 lightyears away just south of Aquarius. Each star is half as massive as the Sun and older than 500 million years. When spotted, two stars orbited each other at 300,000 mph, taking under five days to complete an orbit. The other couple had orbit speed of 120,000 mph and takes 55 days for an orbit. The orbit radii are .06 and .26 AUs. An extrasolar planet m igh t h a ve for m ed fr om the merger of two planets. 2M1207B orbits a brown dwarf 170 light-years away towards Centaurus. In 2006, astronomers suggested a disk cloaked some of its light. Now, they propose 2M1207B is only the size of Saturn. The object's estimated radius is 31,000 miles with a mass 80 times Earth's. The most massive black hole in t h e u n iver se t ip s the scales at 18 billion times more massive than the Sun. Six times more massive than the previous record, it's orbited by a smaller black hole, which allowed measurement of the giant's mass. The binary black-hole system powers a quasar, OJ287, 3.5 billion light-years away in Cancer.
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Briefs: Odds Change, Asteroid-Mars Collision Ruled Out
The possibility of a collision b et ween M a r s a n d an approaching asteroid January 30 was ruled out. Tracking asteroid 2007 WD5 from four observatories so reduced uncertainties that the impact odds dropped to 1 in 10,000. The best estimate was for the asteroid to pass at 16,155 miles or, at worst, no closer than 2,485 miles. The asteroid was discovered in November. Initial observations lowered the odds of an impact to 1 in 25 before further refinements came in. The asteroid is big enough to have blasted a half-mile-wide crater. 2007 WD5 is a 164-foot-wide asteroid that circles the Sun on a path ranging from just outside Earth's orbit to the outer fringe of the asteroid belt between Mars and Jupiter. It's similar in size to the object that crashed into northern Arizona to form Meteor Crater 50,000 years ago. Astronomers discovered t h e you n gest p la n et t o date circling a Sun-like star. The planet's an estimated 8 million-10 million years old. No planet younger than 100 million years old had been detected. The planet's so infantile it's in the star's protoplanetary disk, showing planets can form before the disk is dissipated by stellar winds and radiation. At nearly 10 Jupiter masses, the planet circles .04 AUs from its host star, TW Hydrae, in Hydra. The gassy hot Jupiter orbits its star in 3.56 days. The host star is 180 light-years from Earth. The planet was discovered by measuring a wobble in the star due to gravitational tug from the planet. Saturn's poles h a ve su r p r isin g swir lin g h ot sp ot s that persist even through years of polar winter. They're areas in Saturn's gaseous atmosphere over its poles that are considerably warmer than surrounding air, about as warm as the atmosphere at Saturn's equator. Processes in the atmosphere, not solar irradiation, may create the hotspots since the North Pole faces away from the Sun. Air being sucked downward at the poles may cause the hotspots, while air moving upward may be creating a cold "collar" around the hotspots. As unusual as the hotspots is the warm hexagonal ring of air surrounding the cold collar of the northern-hemisphere hotspot. In the wee hours of our solar system, m a ssive explosions on the Sun might have sent gases whizzing so fast they embedded into tiny rock particles. These then went beyond Neptune and into a comet. New research reveals surprisingly large amounts of helium and neon in
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samples taken from comet Wild 2. Results suggest the gases came from a region very near the young Sun. A new solar cycle is u n d er wa y. T h e fir st su n sp ot of an 11-year cycle appeared in the Sun's northern hemisphere. The frequency of sunspots rises and falls during these cycles, and the start of a new cycle indicates they're likely to begin increasing. Sunspots can affect Earth by disrupting electrical grids, airline and military communications, GPS signals and cell phones.

Astronomers have observed a j et of m a t t er sp iraling from an infant star. The jet, which shoots out in two directions, from end to end extends 16,000 AUs. The protostar, Herbig-Haro 211, is 1,000 light-years away in Perseus. Scientists estimate it started gathering stellar material about 20,000 years ago. Ultimately it will grow into a star like the Sun, but now is 6% its mass.
Dust seeded formation of r ock y p la n et s su ch a s Earth. But where most dust came from was uncertain until now. Astronomers have found 10,000 Earth masses of dust surrounding Cassiopeia A, the remnants of a supernova 11,000 light-years away, with silicates, carbon, iron oxide, aluminum oxide and other dust-forming chemicals. Vivid eruptions of the Northern Lights ea r ly la st year broke speed and energy expectations, and provided info on the source of the storm's energy. On March 23, an auroral substorm erupted over Alaska and Canada, producing auroras for more than two hours. The auroras sped westward, crossing 15 degrees of longitude in less than a minute. Total energy of the event was estimated equal to a 5.5-mag quake. Satellites found evidence of magnetic ropes--twisted bundles of magnetic fields-connecting Earth's upper atmosphere to the Sun. Scientists believe solar-wind particles flow along these ropes, providing energy for geomagnetic storms and auroras. The 1908 Tunguska explosion in Sib er ia might have been caused by an impacting asteroid far smaller than previously thought, computer simulations suggest. Scientists earlier calculated the explosion as possibly 1020 megatons of TNT. In the last decade, researchers conBriefs continued on page 11


Briefs: Tunguska Asteroid Maybe Smaller than Thought
Continued from page 10 jectured the event was triggered by an asteroid exploding in Earth's atmosphere that was 100 feet wide and 560,000 metric tons in mass. It's now thought it was three-four times smaller in mass and perhaps 65 feet in diameter. The explosion was more likely 3-5 megatons. NASA scientists discovered wh a t m igh t for m winding channels in Mars' surface. The features form in an area of the South Pole. New observations boost theories the patterns may be sculpted by springtime outbursts of carbon dioxide gas from underneath the frozen carbon dioxide polar ice cap. Some channels radiate from a center point. Others are like lace or scaly lizard skin. The U. N. General Assembly p r ocla im ed 2009 the International Year of Astronomy. It's an initiative of the IAU and UNESCO, celebrating the first astronomical use of the telescope by Galileo. IYA2009 will highlight global cooperation for peaceful purposes and the search for our cosmic origin. It aims to stimulate interest, especially among young people, in astronomy and science under the theme "The Universe, Yours to Discover." Collaborations between professional and amateur astronomers will be a key part of the effort. A cosmic explosion t h a t seem s t o h a ve com e ou t of nowhere, thousands of light-years from the nearest collection of stars and one of the brightest last year, was in Gemini. The explosion was a long-duration gammaray burst (GRB) 9.4 billion years ago, thought to be powered by death of a massive star. But images taken after the glow faded showed no galaxy at the location. The nearest galaxy is 88,000 light-years away and there's almost no gas lying between the burst and Earth. The burst's spectrum revealed no signs of gas and dust absorbing the light of the afterglow. Perhaps the star formed in the outskirts of an interacting galaxy. Saturn's rings may be as old a s t h e sola r syst em , debunking theories they formed during the dinosaur age. Astronomers had thought Saturn's rings likely formed 100 million years ago from leftovers of a meteoric collision with a moon, based on `70s Voyager data. New Cassini data suggest the rings existed as far back as 4.5 billion years. The probe also found ring particles constantly shattering and that rings may sini UV spect reflected from regrouping to form new rings. The notion be a permanent feature was based on Casrograph observations, which viewed light the rings and stars passing behind them.

The Milky Way has two distinct parts in it s ou t er reaches that rotate in opposite directions. It has a core where stars are tightly packed and orbit furiously around the central black hole. And there's a big flat disk with spiral arms, also orbiting the galactic center. The inner and outer halos probably formed in different ways at different times. The main galactic disk rotates at an average 500,000 mph. The inner halo orbits in the same direction at 50,000 mph. The outer halo, a sparsely populated region, spins in the opposite direction at 100,000 mph. Inner-halo stars have three times as many heavy atoms. Researchers believe a n cien t volca n oes cou ld h a ve released sulfur that warmed up Mars enough for liquidwater oceans. Evidence of liquid water 3.8 billion years ago implies Mars was once relatively warm. Scientists have often proposed the early atmosphere was rich in carbon dioxide, but past findings suggested carbon dioxide on its own couldn't get early Mars above water's freezing point. Also, a carbon dioxide-rich atmosphere would have led to massive deposits of limestone and other carbonate rocks, which are absent. Volcanic gases loaded with sulfur could help solve the puzzles of missing rocks and how Mars got warm enough for oceans. Astronomers have confirmed t h e exist en ce of a lopsided "doughnut" of electrified plasma surrounding Saturn. The electric phenomenon, extending 746,000 miles into space, rotates. Most of Saturn's ring current plasma, largely oxygen, comes from its ice-spewing moon Enceladus. Saturn drags heavy oxygen ions around the planet in a counter-clockwise direction. Experiments on sh u t t le At la n t is t o t h e test how exposure to radiation might change during a simulated Mars mission. Any Earth going to Mars might contaminate efforts to find of Martian life. Bacteria that can survive long on comets or interplanetary shards also provide that seeds of life are everywhere. I SS will bacteria bacteria evidence journeys evidence

Briefs continued on page 12
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Briefs: NASA Plans to X-ray the Moon's Insides
Continued from page 11 European Space Agency gover n m en t s will finance early work in 2008 on a $1.5-billion Mars rover mission that likely will have participation by the U. S. and Russia but won't be definitively approved by ESA governments until November. The decision to spend $117 million this year will preserve ESA's ability to launch the rover package in 2013 by permitting purchase of hardware needed now to meet the date. NASA will provide one instrument and a second working with ESA. NASA plans to X-ray in t er n a l lu n a r im p er fections to solve mysteries about the Moon's insides. Twin spacecraft will launch in 2011 and map the lunar gravity field for 90 days. The mission will measure gravity at different points, which should reveal differences as slight as 1 million times weaker than Earth's gravity. The data will be 1,000 times better than other gauges of lunar gravity. A new study finds organic compounds con t a in in g carbon and hydrogen could have formed early in the history of Mars. It indicates raw material for life should be easy to drum up on any cold, rocky world. Scientists reexamined the Allan Hills 84001 meteorite from Mars, believed by some scientists to contain direct signs of life on Mars. Scientists then looked at terrestrial rocks from Norway, created by volcanic eruptions 1 million years ago in conditions thought similar to ancient Mars. They found organic material occurs within tiny spheres of carbonate minerals in Martian and Earth rocks. In the Mars meteorite, organic material didn't originate from Martian life forms but from chemical reactions within the rock. Traces of an extrasolar planet's h a zy r ed su n set have been detected for the first time. Astronomers pointed the Hubble at HD 189733b, a gaseous Jupiter-like world 63 light-years away, as it passed in front of its parent star to catch a glimpse of the planet's atmosphere. Light traveling through the planet's atmosphere appeared red in front of its yellow star. Images taken by five spacecraft t h a t or b it ed t h e Moon in the '60s are proving invaluable in planning our return. In 1966 and 1967, Lunar Orbiter spacecraft returned more than 2,600 images and photographed 99%
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of the surface. Images will help select manned landing sites and earlier robotic landings. They might also help calculate how often the Moon gets hit by meteorites. Images will also aid in evaluating outpost architecture and designing preliminary routes across the surface. One of the fastest-moving stars ever is ch a llen ging theories to explain its speed. The star is racing out of the Milky Way at 3 million mph from the Puppis A supernova remnant, leftovers of a star that exploded 3,700 years ago. Other stars have been flung from the Milky Way but few this fast. The star has traveled 20 lightyears and will take millions of years to leave the galaxy. A rare new kind of star m a y h a ve b een d iscovered. It's much like the white dwarf our Sun will become save for a mysterious shroud of carbon ash. More than 97% of stars in our galaxy are expected to become white dwarfs. Until now, known white dwarfs had atmospheres rich in hydrogen or helium. Unexpectedly, scientists have found eight with skies primarily of carbon. As white dwarfs form, t h ey get a k ick t h a t p r op els them to thousands of miles per hour. Astronomers looked at distribution of white dwarfs in the ancient globular cluster NGC 6397. Because its stars were very massive before burning out as white dwarfs, and massive stars tend to gather at the cluster's core, astronomers assumed most of the new white dwarfs would dwell at NGC 6397's center. But they discovered young white dwarfs at the edge of the globular cluster. A project to build a p ion eer in g t elescop e in C h ile got a $30 million boost with donations from Microsoft chairman Bill Gates and former company executive Charles Simonyi. Simonyi is donating $20 million and Gates $10 million to pay for three major mirrors in the Large Synoptic Survey Telescope, a nearly $400 million project that will be able to survey the entire sky every three nights, something never done. Astronomers anticipate surveying the heavens for 10 years, with observations starting in 2015. The telescope will take an im-

age every 15 seconds nightly, and its camera--the world's largest and most powerful digital device-- will read out the image in 2 seconds. Scientists will be able to quickly find Earth-threatening asteroids and supernovas, and map out 100 billion galaxies.


Events on the Horizon February 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 Friday, February 1, 6:15 p. m. AAA lecture, P Nergis Mavalvala, associate professor of physics at MIT, will speak on "Detecting Gravitational Waves: LIGO and the Search for the Elusive Wave" in the Kaufmann Theater of the AMNH. Saturday, February 2, 5-6:30 p. m. Custer Institute and Observatory, Southold, N. Y., P AAA member Sam Storch of the department of physical sciences at Nassau Community College will speak on "To the Stars through Rugged Ways," an historical look at how our understanding of the universe evolved. Suggested donations. Info: CusterDonna@yahoo.com. Saturday, February 23, 1 to 4 p. m. Observers Group, M, HQ Next date: March 29. Monday, February 25, 7:30 p. m. Hayden Planetarium lecture, P, AMNH In "The First Copernican," Dennis Danielson of the University of British Columbia will discuss mathematician Georg Jochim Rheticus, without whom Copernicus' theory of a heliocentric universe may have been lost. Wednesday, February 27, 7 p. m. Quarterly AAA board meeting, M, HQ NOTE: Many AAA nighttime observing activities are on hiatus, with next dates as follows: Cadman Plaza, Brooklyn, April 8; Carl Schurz Park, Manhattan, April 25; Floyd Bennett Field, Brooklyn, March 14; Prospect Park, Brooklyn, TBD.

Saturday, February 9, dusk Stargazing, Great Kills, Staten Island, P, T, C Next date: March 8.
Thursday, February 14, 6:30 p. m. Recent Advances in Astronomy Seminar, M, HQ Next date: March 6. Wednesday, February 20 Lunar Eclipse Observing, P Observing of total lunar eclipse at Carl Schurz Park, Manhattan. Eclipse begins at 8:43 p. m., ends at 12:09. Saturday, February 23, 10 a. m. to noon Central Park solar observing, P, C At the Conservatory Waters. Next date: March 29.

Fedrick continued from page 2 Syrtis Major had crossed the Martian meridian. Dark Martian features such as Syrtis Major stood out against a pale coral pink disk. I could barely make out the north polar cap on December 25 and on New Year's Eve. The north polar cap was tilted once again toward us, affording our best view of it since the late '90s. Saturn began to rise over the trees to my east by around 11 p. m. on New Year's Eve and presented an eerie view of its pale yellow disk and thin rings tilted more nearly edge-on than in many years. By early January, Mars was already appearing noticeably dimmer than in early December, but by then Saturn was appearing in the late evening sky and Jupiter was about to return to the morning sky as a new season for observing the gas giants was about to begin.
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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're interested in writing for Ey epiece, contact editor Dan Harrison at editor@aaa.org or (914) 762-0358.


Dark Energy continued from page 1 among scientists indicates dark energy accelerates the expansion of the universe, makes up 70% of its energy mass and came to dominate around 5 billion years ago, though it had been around longer. (Riess spoke to the AAA earlier. See the Ey epiece archives at aaa.org for the December, 2005 issue.) During the first 7 billion years of t h e u n iver se's existence, dark matter dominated, and the universe was decelerating, Riess noted. "The universe is expanding about 20% faster than 5 billion years ago and the transition point when the universe transitioned from slowing to speeding up was about at that time." Riess made the analogy that "dark matter is like the rubber bands of space that hold back and try to retard the expansion and today the dark energy is being labeled as anti-gravity like the springiness of space that pushes against it." But Riess emphasized that "we're a long way from knowing what dark energy is....It may have been around from the inception of the universe but our measurements aren't good enough to tell us that."

vacuum energy of empty space, required by quantum mechanics? If so, another question arises: Will dark energy always be there? Or could dark energy be dynamical, more like an energy field such as electricity, magnetism or inflation? This leads to a different question: Can dark energy change strength as the universe evolves? Or a third possibility has been offered: Could dark energy be a part of a modified definition of gravity? "Maybe Einstein's theory isn't perfectly correct," Riess said. Riess stated that the physics of dark energy will determine the fate of the universe and asked the question, "Will it end in a big crunch, a big chill or a big rip?" Read more about dark energy a t h u b b lesit e.or g. Search for dark energy. Link from there to Riess's site, his articles and a video of the interview with him that appeared on The News Hour with Jim Lehrer February 27, 1998. Or read books Riess suggested: "The Extravagant Universe: Exploding Stars, Dark Energy and the Accelerating Cosmos" by Robert P. Kirshner or "The

Correction
Last month's ob it u a r y a r t icle on for m er AAA president Fred Hess, who died December 13, stated that his funeral was October 15. It was December 15.

Riess described cosmologists' three best guesses, in order, as to the nature of dark energy. Could it be a reimagination of Einstein's cosmological constant, the

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