Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.aaa.org/EyepieceFiles/aaa/2014_12_December_Eyepiece.pdf Дата изменения: Wed Oct 14 23:25:36 2015 Дата индексирования: Sun Apr 10 03:47:22 2016 Кодировка: Поисковые слова: universe

ESA Rosetta for OSIRIS Team

Philae, imaged upon release from the Rosetta spacecraft on Nov 12, had a bumpy landing on Comet 67P, but the probe has already found organics!

Journal of the Amateur Astronomers Association of New York
December 2014
Volume 62 Number 12; ISSN 0146-7662

Hubble: The Living Legend We Nearly Lost
AAA 2014 LECTURE SERIES By Leo Genn On November 14. former AAA Member David Gaynes discussed the making of his film Saving Hubble for the second lecture in AAA's free Friday NASA The Hubble Space Telescope, deployed by night series at the Kaufman Auditorium Space Shuttle Discovery in 1990. of the American Museum of Natural History. In his "Hubble Lives!" presentation, he admitted that his film is not really about Hubble or even astronomy, but rather, it is a portrait of America ­ a film about the American people at a particular moment in history. "Hubble was a metaphor for something," Ga ynes sa id cr yptically, "I just didn't k now w hat that som ething w as." In 2004, a launch to the Hubble Space Telescope was scheduled to install replacement parts, including the Wide Field Camera 3. Without the parts, Hubble could cease operating in 2006. Hubble had been serviced four times before, but in the wake of the Columbia Space Shuttle disaster of 2003, NASA Administrator Sean O'Keefe cancelled the mission, rather than risk the lives of astronauts. The cancellation sparked an outcry from scientists and the public and prompted debate in Congress. Gaynes had never seen any of Hubble's images when he heard the rescue mission was cancelled, so he looked them up. Iconic images like the Pillars of Creation in the Eagle Nebula (M16) blew him away. Inspired NASA, ESA, STScl, J. Hester and P. Scowen by the images, and by the Images like this of Pillars of Creation in gonzo style journalism of the Eagle Nebula (M16) taken by Hubble inspired Gaynes and others to fight Hunter S. Thompson, as to save the space telescope. portrayed by Johnny
AAA Lecture (cont'd on Page 4)

Photographing Exoplanets: Star Light, Too Bright!
ASTRO TALKS Richard Brounstein Bright and beautiful stars wonderfully illuminate the universe. However, their brilliant light gets in the way when trying to photograph exoplanets outside of the Solar System. T h e K ep ler sp a ce ob ser va t or y h a s d et ect ed thousands of planets, large and small, orbiting bright stars in our galaxy. We know they exist, and we know their masses and dimensions, but we have only been able to image a few. Space and groundbased telescopes have been able to observe very large extrasolar gas giants. The first direct image taken of an exoplanet was made in 2005. Orbiting a brown dwarf host star at a distance 9 times greater than Neptune's distance from the Sun, the planet was so large, it was like imaging ESO Brown dwarf 2M1207 and its giant another star. co panion the But in the search for planetary vermmaged, ­akenfirst texoplanet e i t by he Earth-like planets, it is dif- European Southern Observatory's Very Large Telescope in Chile ficult to photograph small rocky worlds that orbit close to their host stars in the habitable zone. The intense starlight of their suns overexpose any image. A star is billions of times brighter than the light reflected by even the largest gas giants that may orbit it. Imaging smaller worlds is like trying to photograph a firefly next to a search light. The challenge is daunting. Enter the starshade. Developed at NASA's Jet Propulsion Laboratory for the Exoplanet Exploration Program, the starshade is designed to launch with a companion telescope. It is made of an extremely thin, lightweight metal shield that opens up like a blossoming flower. Once deployed, the starshade blocks out the excessive light of a star and allows the space telescope to image an orbiting planet. Dr. Sara Seager chairs the Science and Technology Definition Team (STDT) for starshade, one of two teams formed in 2013 to study mission concepts for the direct detection of extrasolar planets. Members of AAA were invited
Starshade (cont'd on Page 5)

THIS MONTH: AAA Lecture on Dec 5 and Winter Skies Telescope Party on Dec 15.


December 2014

WHAT'S UP IN THE SKY
AAA Observers' December Guide
By Tony Faddoul

Coming in for a Landing
On November 12, the European Space Agency's Rosetta spacecraft deployed the lander Philae to 67P/Chury umov Gerasimenko, ma kin g it th e fir st ma n -made object to land on a comet. Now seems like a good time to review other places where humans have made their mark. Here is a list of successful landings made on six bodies in our Solar System. Moons Earth's Moon: On January 31, 1966, unmanned Soviet spacecraft Luna 9 landed successfully on the moon, marking the first soft-landing on an object in space. That mission was followed by more unmanned landings. On July 20, 1969, NASA's Apollo 11 reached the lunar surface for the first human landing on any extra-terrestrial body. Saturn's Moon Titan: On January 14, 2005, the Huygens probe successfully landed on Titan, part of the Cassini Huygens joint effort between the U.S., Europe, and Italy. Unmanned Orbiter Cassini left Earth on October 15, 1997 and it is still active today after two mission extensions in 2008 and 2010. Planets Venus: On December 15, 1970, Venera 7, a Soviet spacecraft, became the first spacecraft to land on another planet. Previous missions had failed to reach Venus's surface or stopped transmitting data before impact. Venera 7 and subsequent successful landers ­ the last in 1985 ­ transmitted for only a matter of minutes, ultimately succumbing to the extremely high pressure and temperatures on Venus. Mars: On July 20, 1976, NASA's Viking 1 became the first spacecraft to successfully land on Mars. Launched in 1975, the lander operated until November 1982, surpassing its orbiter, which was powered down early in 1980. Prior to that, the Soviets came very close with the Mars 3 spacecraft. On December 2, 1971, the probe was released during a huge sandstorm; Mars 3 successfully landed, but transmitted for less than 20 seconds before it failed. Today, active landers on Mars include NASA's Opportunity and Curiosity rovers; the Spirit rover lost contact in 2010. Near-Earth Asteroids 433 Eros: Or igin a lly design ed a s a n or biter , NASA's NEAR Shoemaker probe made an improvised landing on February 12, 2001, becoming the first object to touch down on an asteroid. It stayed active for about 16 days. 25143 Itokawa: On November 20, 2005, the Japanese sample-return probe Hayabusa landed on the asteroid, but it was unable to collect samples. A detachable mini -lander MINERVA failed to reach the surface the week before. Five days later, Hayabusa tried again and successfully activated sampling. Its sample capsule returned to Earth on June 13, 2010 with the first dust ever collected from an asteroid.
Sources: earthsky.org; nasa.gov; global.jaxa.jp; braeunig.us; planetary.org.

December's Evening Planets: Mars will be up until 8:00 PM in Capricornus the Sea-goat. Blue Neptune can be found in Aquarius the Water Bearer until 11:00 PM, setting earlier every night until 9:00 PM by the end of the month. Uranus will be in Pisces the Fish all night long. Jupiter rises between Cancer the Crab and Leo the Lion around 10:00 PM in early December. It rises earlier each day until 8:00 PM by the end of December. Mercury and Venus will be visible for an hour after sunset in Sagittarius the Archer during the second half of December, and dwarf Pluto will be up all month for an hour after sunset in that constellation.

December's Evening Stars: Spot The Winter Triangle
this month starting at 8:00 PM: Sirius, the brightest star viewed from Earth is in Canis Major the Great Dog, Betelgeuse is in Orion the Hunter, and Procyon is in Canis Minor the Small Dog. Also find the stars Deneb in Cygnus the Swan, Aldeberan in Taurus the Bull, and Capella in Auriga the Charioteer. See the stars of constellations Andromeda, Cassiopeia, Perseus, Cepheus, Draco, Pegasus, Aquarius, Aries, Taurus, Pisces, Capricornus, and the two Dippers.

December's Morning Planets: Uranus will linger
until around 2:00 AM at at midnight by the end of Cancer the Crab and Leo t visible in Libra the Scales the beginning December, setting the month. Jupiter is up between he Lion until sunrise, and Saturn is for an hour before sunrise.

December's Morning Stars: The Winter Triangle of
Sirius, Betelgeuse, and Procyon will be up until morning throughout December. Spot Capella in Auriga the Charioteer, Arcturus in Bootes the Herdsman, and Aldeberan in Taurus the Bull, along with the stars of constellations Leo, Gemini, Orion, Andromeda, Cassiopeia, Cepheus, Draco, Perseus, and the two Dippers.

December "Skylights"
Dec Dec Dec Dec Dec 6 9 11 12 14 Full Moon at 7:27 AM Jupiter stationary at 2:00 AM Moon 5° south of Jupiter Moon at apogee (251,390 miles from Earth) Geminid meteor shower peaks Last Quarter Moon at 7:51 AM Moon is 1.5° north of Saturn Winter solstice 6:00 PM New Moon at 8:36 PM Uranus stationary at 1:00 AM Moon at perigee (226,670 miles from Earth) First Quarter Moon at 1:31 AM
Times given in EDT.

Dec 19 Dec 21 Dec 22 Dec 24 Dec 28

Follow veteran sky watcher Tony Faddoul each month, as he points our eyes and our scopes toward the night sky.

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December 2014

Cleveland Rocks a Solar Eclipse
FOCUS ON THE UNIVERSE By Stan Honda October was "eclipse month" with two observable from North America. Here in New York, I was barely able to photograph the total lunar eclipse on Oct 8. The partial solar eclipse on Oct 23 threatened to be clouded out too. So, to capture that event I would have to think outside of the box ­ and outside of New York. A week or so before the solar eclipse, I consulted a map to see where within driving distance from my home it would be visible. Cleveland turned out to be the nearest spot. So, on the morning of the eclipse, I got up early and drove eight hours from New York City to downtown Cleveland. I had been in contact with the Cuyahoga Astronomical Association (CAA) and learned they were having public viewings of the event. In two parks, I discovered people holding compasses, charting the path of the sun ­ a sure sign of astronomers! That very clear afternoon, I set up in Voinovich Park on the Lake Erie waterfront. CAA Member Jay Reynolds welcomed me, astonished to learn I had driven all that way. CAA President Bill Murmann and Vice President Tim Campbell were also very accommodating. "Clev eland is closer to the Sun than New York," Tim joked, pr edicting I would get better pictures there than back home. In time for the 5:42 PM eclipse, the club set up about six or seven telescopes, including a beautiful, museum-quality 5inch Alvan Clark refractor, built in 1874. The scope is owned by Gary Kader, Director of the Burrell Observatory at Baldwin Wallace University. With his scope, he projected a large, sharp image of the sun on piece of white cardboard, which allowed park visitors to view the eclipse together. I first set up my large Bogen tripod with a Nikon 400mm f2.8 lens and 1.7x teleconverter, creating a 680mm on my Nikon D800. A Thousand Oaks Optical black polymer solar filter provided me with a safe view through the lens. I was treated to a great sight even before the eclipse began ­ Sunspot AR2192 was visible, even with the naked eye

Stan Honda

Time-lapse of setting sun during partial eclipse on Oct 23. Sun images shot 4 minutes apart. Nikon D4 camera on tripod with 70-200mm zoom lens at 135mm, Thousand Oaks Optical black polymer solar filter (for sun images). Exposure for sun- 1/1000 sec, f8, ISO 200, exposure for foreground scene (without filter): 1/1600 sec, f13, ISO 200.

through solar glasses. The maximum eclipse coverage was about 40%, and the sunspot remained visible throughout the event. I shot most of the eclipse with the long telephoto lens, even trying to get some dramatic shots as it descended into a low cloud bank on the horizon. For a second view, I set up a Nikon D4 on a tripod with a zoom lens set at 135mm and aimed through some trees in the park. I set an intervalometer to trigger the shutter every minute as the sun arced downwards for the 40 -minute eclipse. Back home, I selected 10 frames shot 4 minutes apart. Using Photoshop, I layered them with a foreground image I took after sunset. Shooting through the trees added a depth to the picture that is not typically found in eclipse sequences. Capturing that final image during this striking celestial event and experiencing the hospitality of the CAA made the long drive to Cleveland well worth it. With the holiday season upon us, you may be looking for the perfect gift for your astronomically -minded friends, or maybe you want to treat yourself. Here are a few ideas to get you started: The iOptron SkyTracker camera mount ($369-399) is one of the best accessories you can buy to improve your night sky photos. It's a small version of a tracking telescope mount and holds a small camera and wide angle or moderate telephoto lens. The SkyTracker lets you shoot long exposures of one minute or more without trailing stars. A landscape in the frame will be blurry, but a half-speed setting splits the difference between the land and the motion of the stars for exposures less than one minute. With the included polar scope, you can align with Polaris, and the SkyTracker will follow the stars all night long. It runs on just four AA batteries. The white model is $30 more, but it is easier to work with in the dark. You'll need a separate ball head to hold the camera: the 3Pod H1 Ball Head ($49.95) with quick release plate is about the right size. For solar photography, Thousand Oaks Optical sells black polymer solar filter sheets that protect your camera and eyes
A Cleveland Eclipse and Holiday Hints (cont'd on Page 4)

Stan Honda

Mid-eclipse with some clouds: Nikon D800 camera on tripod, 400mm lens with 1.7x teleconverter (=680mm), Thousand Oaks Optical black polymer solar filter. 1/500 sec, f8, ISO 800.

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December 2014

AAA Lecture (cont'd from Page 1)

Depp in the film version of Fear and L oathing in L as V egas, Gaynes hit the road with his Director of Photography, Eric Budney. "Hubble is the m ost am az ing thing m ank ind has ever invented," he told Budney a t the time. Gaynes described his road trip and the people he met and interviewed along the way ­ scientists, astronauts, and regular Americans. Their sentiments toward Hubble and NASA reflect the mood of the country in the mid -2000s. Gaynes also described some of the realpolitik that ultimately prompted reinstatement of the Hubble rescue mission. He recounted a conversation with Steven Beckwith, former Director of the Space Telescope Institute. Over a period of about five months, Beckwith booked time with Hubble's Wide Field Camera 2, directing it toward the Fornax constellation at "the dullest, emptiest place in the sky," as it was later called by Neil DeGrasse Tyson. The long exposure of a one pixel-wide section of dark nothingness yielded an image of about 10,000 galaxies formed shortly after the Big Bang. In 2004, Beckwith released the image, now known as the Hubble Ultra-Deep Field, knowing its startling revelations would generate public pressure on politicians to save Hubble. In 2006, O'Keefe's successor at NASA, physicist and aerospace engineer Michael Griffin, reversed the decision to cancel the Hubble service mission. President George W. Bush's appointee O'Keefe, who had a reputation as a "bean counter" and no formal training in science or engineering, comes across as the villain in S av ing Hubble. "There is evidence to show he was the villain," sa id Ga ynes. O'Keefe approved 29 of 30 manned missions; Hubble was the only
A Cleveland Eclipse and Holiday Hints (cont'd from Page 3)

one scrapped. However, those approved were flights to the "safe haven" of the International Space Station, where people and resources could support astronauts ­ far less risky than visiting the lonely Hubble outpost, where they could be stranded. Stan d O'Keefe's decision was Filmmaker David Gaynes with AAA Honma Me supported by members ber Bruce Kamiat. Bruce appears in the of the Columbia Acci- film Saving Hubble. They reunited at the dent Investigation Board. AAA lecture "Hubble Lives!" on Nov 14. During the Q&A, an audience member asked if Gaynes felt that keeping Hubble running was worth putting human lives at risk. "I can't say that the m ission justif ied risk ing human life," r eplied Ga ynes, but it wa s clea r tha t the a str ona uts who went were fully aware of the risks and wanted to go. After several delays, the Hubble service mission finally launched in 2009. By that time, many vital repairs were needed. NOVA's "Hubble's Amazing Rescue" captures the exciting story of the difficult mission, while National Geographic's "Hubble's Amazing Universe" offers a look at the space telescope's crucial scientific contributions. The cancellation and revival of Hubble's service mission reveals a constant state of flux at NASA. Gaynes' film demonstrates that equally constant is Americans' shared human drive to explore and understand our universe.
Lookout for Leo's review of Saving Hubble in next month's Eyepiece.

trail shots. Most importantly, you can trigger your camera without any vibration. Some triggers are made for specific models, so make sure you pick the right one. Finally, you can never have enough memory!...cards, that is. Newer cameras have larger files, and very large RAW files are essential for night sky photos. Buy the biggest you can afford. Stay with the major brands like SanDisk and Lexar for quality. I prefer the fast versions by SanDisk Extreme Pro or Lexar Professional, since the camera will write faster and you will be able to download quicker. Happy holidays and happy imaging!

Stan Honda

Explore more night sky photography at

Sun setting in the clouds after partial solar eclipse on Oct 23: Nikon D800 camera on tripod, 400mm lens with 1.7x teleconverter (=680mm). 1/8000 sec, f40, ISO 50.

www.stanhonda.com.

before aiming at the sun. You can cut them to size; a 12" x 12" sheet ($25) is enough for several lenses. It seems like there are more shutter release triggers coming out every day, both wired and wireless, including the Vivitar LCD Digital Timer Shutter Release ($29 for selected Canon cameras), Seculine Twin1 ISR Interval Shutter Release ($49), Phottix Aion Wireless Timer and Shutter Release ($93), and Hahnel Giga T Pro 300' Wireless Shutter Release Timer Remote ($91). You can set very long exposures ­ over 30 seconds ­ and take multiple series for star 4

Submit your photography questions to

stanhonda@gmail.com.
Stan Honda is a professional photographer for Agence FrancePresse and covered the Space Shuttle program for five years. In his "Focus on the Universe" column, he shares his night sky landscapes and explores his passions for astronomy and photography.


December 2014

The Case for Oddball Earth or Why It's a Very Lucky Planet
BOOK REVIEW By Tom Haeberle "If we look at the rocks beneath our feet and the stars above our heads, the evidence they present points to the Earth being a very peculiar place," sa ys geophysicist Da vid Wa ltha m in his book Lucky Planet: Why Earth is Exceptional--and What That Means for Life in the Universe (Ba sic Books, 2014; $26.99). Also an astrobiologist, Waltham argues that Earth's climate stability is one of the primary factors that makes it able to support life; our four -billion-year stretch of "good weather" is statistically unusual, and chances are slim that we will ever discover intelligent life elsewhere in our universe. So, don't pin your hopes on an extraterrestrial encounter. In his prologue, Waltham tells a tale of two planets: Earth and "Nemesis." They both start off as similar, uninhabitable hellholes that over four billion years are transformed into oxygen -rich life-bearing planets with large plants and ferocious ani mals. Earth's dinosaurs and Nemesis's "dragons" would reign on their home planets' as the most complex organisms. But when the same disaster strikes both worlds, in the form of a giant asteroid, only one recovers ­ Earth. A planet has to be pretty weird for creatures like humans to evolve as quickly as 65 million years after an asteroid impact.
Lucky Planet Review (cont'd on Page 6) Starshade (cont'd from Page 1)

to meet her on November 4 and hear details about the project firsthand. The key to the starshade's design is its flower shape. If it were a solid disc, light would bend around it and interfere with observations. Such a disc would need to be much larger than the apparent radius of the star to adequately block its light, but then it would also block the light reflecting off of the orbiting planet. The unique shape of the starshade's "petals" overcomes this limitation. The 34-meter diameter starshade diffuses the light, blocking out only that from the luminous star while the lit planet can shine through. It is brilliant in its simplicity. However, the starshade concept is not without its engineering challenges. It requires extremely precise alignment between the telescope and star while taking into account orbital mechanics. The starshade must maneuver in perfect formation with the telescope to a distance, accurate to within one meter, that is many kilometers away from it. Meanwhile, the automatic unfurling the starshade's petals requires an even greater degree of accuracy ­ to within one millimeter. Maintaining that kind of accuracy over such large distances sounds like an impossible task, but the vacuum of space actually provides a stable environment. MaNASA neuvering the starinside a Artist's depiction of a deployed Star Shade. The shade flower petal shape is what diffuses light so effec- planet's atmostively to block the light of a distant star. phere would be much more diffi-

cult. Current spacecraft technology is capable of making micro-maneuvers to accomplish the intricate alignments. Unfortunately, the three-year lifespan of the proposed starshade mission limits the number of exoplanets it could help image. In the first 18 months, its companion telescope would study 55 stars where it can detect Jupiter -sized planets plus 22 stars where it could also image smaller Earth -sized planets. The last 18 months would be spent revisiting those stars to make more detailed observations. But, if starshade could help us image even just one Earth-like planet, it would be worth the endeavor. Direct images might reveal other habitable worlds in our galaxy, detailing geologic details like continents and oceans, while spectroscopic readings could find oxygen and ozone in their atmospheres. Even more remarkable, direct imaging could detect radiation on a planet or even atmospheric pollutants like carbon monoxide ­ evidence of intelligent, technologically advanced life. With a little flower power from starshade, we may one day discover that we are not alone in the universe.
Sources: nasa.gov; and eso.org.

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December 2014

Lucky Planet Review (cont'd from Page 5)

Aspiring Against Astronomical Odds
FILM REVIEW By Rori Baldari Sepideh is a 16year-old Iranian teenager who loves astronomy, much to the chagrin of her disapproving family. Shown as part of Radiator Film ApS the Margaret Mead Film Festival at the American Museum of Natural History in October, the documentary, S epideh--Reaching for the Stars, by Danish filmmaker Berit Madsen follows Sepideh over a period of three years. As one might imagine, astronomy and science are not among those interests considered necessary or suitable for girls in Iran. Sepideh's uncle actually threatens her life if she "does anything wrong." So, it is with sheer determination and defiance that she pursues her passion for the stars, toting an 8 -inch Dobsonian telescope around to go observe with her friends in the local astronomy club. In contrast to her family, Mr. Kabiri, a science teacher in charge of the club, encourages Sepideh to pursue astronomy. An avid amateur astronomer himself, Mr. Kabiri also faces obstacles in pursuing his dreams; he has run out of money for the small local observatory he has spent years building. A petition to town officials to fund its completion is rejected. Sepideh also finds a positive role model in Anousheh Ansari, the first Iranian astronaut. Ansari sponsored the first X Prize, the 2004 competition to build and launch a reusable manned spacecraft. Enthralled by videos of Ansari floating weightlessly inside the ISS, Sepideh imagines she will one day follow in her footsteps. But, family pressures begin to wear Sepideh down, and she becomes disheartened; we fear she will give up on her dream. Then, an unexpected phone call one day changes everything. It was a wonderful moment in the film to see tears of joy stream down Sepideh's cheeks as she spoke with her idol, Anousheh Ansari. Ansari vowed to aid Sepideh in her astronomy studies and help her to become an astronaut, if possible. The call inspired more complicated feelings from Mr. Kabiri; instead of being happy for Sepideh, he seemed disappointed and even betrayed that she may then leave the club to pursue her dream. After the screening, Madsen confessed she had contacted Ansari, hoping she would make a call to lift the shadow over Sepideh, and create a happy ending for the film. The Q&A panel following the film included AAA Member Shana Tribiano, who discussed her background and reasons for becoming an astronomy teacher. As the audience exited the museum, AAA Member Christina Pease treated them to views of Gamma Andromedae, with her telescope set up on the sidewalk outside. I would recommend this film for anyone. Stories of perseverance are always inspiring, but S epideh especially reminds amateur astronomers here how easily we may take for granted the pleasures of pursuing our passion.

Nemesis's more typical climate would be too chaotic, and humans could not evolve fast enough to keep up. Waltham describes a chronology of our thinking about Earth that comes full circle: it began as the center of the universe, then it was relegated by Copernicus to an ordinary planet orbiting a sun, and now, it reclaims its status as special. In 1999, Waltham witnessed a total solar eclipse and wondered if any planet with a moon big enough to obscure its sun would be more likely to give rise to intelligent life. Larger moons generate stronger ocean tides on a planet, directly affecting its life. Our Sun and Moon make a perfect match, when it comes to a solar eclipse. He claims that if our Moon's radius was 10 kilometers wider and the early Earth's day was 10 minutes longer, then modern Earth would be so unstable on its axis that it could not sustain higher life. After laying out his further arguments, Waltham concludes that we live in a universe where life like that which has emerged on Earth, intelligent or otherwise, is rare, but it is not vanishingly rare. "T he univ erse is m oderately habitable, and we shouldn't expect flying saucers on the White House lawn any time soon. Advanced civilizations are so far away that we would never be able to communicate with them or observe influences they may have on galactic neighborhoods." At best, we can hope to find very simple and lower forms of life in our own Solar System, perhaps on Mars or Jupiter's moon Europa. Lucky Planet is a well-written book, but its author comes across as a bit pompous at times. He presents himself as alone in his belief that life is rare in the universe, up against the entire scientific community. But, his theory is not a new. In 2000, Peter Ward and Donald Brownlee put forth the same idea that life, especially intelligent life, is exceedingly rare. Their book, R are Earth (Copernicus Books), also comes out to declare that we are likely alone in the universe ­ at least in our neck of the woods ­ and it is just as in-depth and "courageous" as Waltham purports his book to be. Surprisingly, Waltham hardly mentions these like -minded scientists, although he does suggest giving their book a read. Waltham closes his book with grim prediction that the good fortune of Earth's "good weather" will come to an end, due in part to runaway greenhouse gases. It would seem that life anywhere may be short-lived: "W e are part of an ex traordinary miracle and I, for one, feel very lucky."

NASA

Orion, NASA's new spacecraft for manned missions, waits for its Dec 4 test flight at Cape Canaveral, in the wake of two recent launch disasters: Orbital Sciences' Cygnus and Virgin Galactic's SpaceShipTwo. These tragedies created concern for human spaceflight. Meanwhile, three astronauts launched on Nov 23 without any issues and joined their team at the ISS.

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December 2014

Positively Positronic!
Making a Case for Dark Matter
UNDERSTANDING OUR UNIVERSE By Alan Rude Last year, researchers led by Nobel Laureate Samuel Ting of MIT announced that the Alpha Magnetic Spectrometer (AMS), a particle detector operating onboard the NASA International Space Station, had counted more than 400,000 positrons, the anti -matter The Alpha Magnetic Spectrometer (AMS) counterpart of electrons, during 25 billion cosmic ray events. Although the proportion aboard the International Space Station searches for proof of the existence of dark matter. of positrons in the cosmic ray mix seems small, the number detected is actually quite large, considering the nature of these particles. In September, with 41 billion cosmic ray events analyzed and 10 million el ectrons and positrons identified, Ting reported that the number of positrons actually appeared to increase at energy levels wh ere they should be decreasing. Something is creating an excess of positrons. The findings sent shock waves throughout the scien tific community: "It could be a sign of dark m atter," said Ting. Cosmic rays are abundant, but their source remains mysterious. Most originate outside our Solar System. Cosmic rays are made of high-energy particles that do have mass. These particles pass through our bodies and can damage DNA. Long term exposure increases the risk of getting cancer, a major concern for astronauts during spaceflight. For those of us on the groun d, we have an atmosphere to protect us. Earth's magnetic field deflects most cosmic rays. When their particles do collide with mo lecules in the atmosphere, they create an "air shower" of secondary radiation that is less dangerous. The average dose, however, increases with altitude: airline crews are exposed to more radiation than anyone, even nuclear power plant workers. Cosmic rays are comprised 90% by hydrogen nuclei (protons), 9% by helium nuclei (alpha particles of two protons and two neutrons), and a very small amount by the nuclei of the heavier elements lithium, beryllium, and boron. Solitary electrons make up about 1% of cosmic rays. Now, the AMS has found that cosmic rays also contain a minute yet significant amount of antimatter particles--antiprotons and antielectrons (positrons). B ut, CDMS why are they there at all? Positively charged positrons should be destroyed by their negatively charged electron counterparts, because antimatter and matter annihilate each other on contact. As those particles collide, energy rises, and the number of positrons relative to e lectrons in cosmic rays should decrease. The AMS found that positrons decrease overall, but it is happening too slowly. There are mo re positrons than there should be. In fact, at certain energy levels (reaching a peak at 275 GeV), the number of positrons actu ally appears to be increasing. Positrons are being replenished and brand new positrons are being formed. B ut, w hat is their source? The excess positrons found by the AMS may come from dark matter. Scientists believe dark matter is made of hypothetical weakly interacting massive particles, or WIMPs. When two WIMPs collide, they annihilate each other and give rise to other particles, including positrons. "T hese results are consistent w ith the positrons originating f rom the annihilation of dark m atter particles in space," sa id Ting, " but not yet sufficiently conclusive to rule out other explanations." An exotic and sexy hypothesis, dark matter has generated far more excitement than competing theories for the positron excess. Another leading candidate is pulsars. Pulsars are strongly-magnetized neutron stars formed in the aftermath of supernova explosions. They spin on their axes thousands of times a second, flinging particles into space. Among these particles are pairs of electrons and positrons. Meanwhile, a model built by Mattia Di Mauro's team at the University of Turin, Italy, has been able to recreate the AMS results without resorting to dark matter. However, "It is still possible to v ary the astrophy sical param eters to include a dark-matter contribution and be compatible with observations," she noted. Michael Turner at the University of Chicago calls the AMS results "beautiful," a nd a gr ees tha t WIMP collisions fit the da ta , "but as Carl Sagan taught, extraordinary claims require extraordinary evidence, and we are not there yet." He a dmits tha t the positr on excess might be due "to astrophysics we don't yet understand, rather than dark matter annihilations." Despite the uncertainty, the results mark a triumph for Ting, who all but willed AMS into orbit. Ready to launch after its assembly at CERN, the AMS nearly found itself permanently grounded following the Space Shuttle Columbia disaster in 2003. Ting worked tirelessly for years to promote the project, and in 2008, he secured a congressional mandate for an AMS launch. But during that time, the AMS costs MS ao n ballooned to $2 billion. That giant price tag still has some shaking their heads. ATheColliobofratiositrons to combined positrons and rat po Gregory TarlИ, a physicist at the University of Michigan, is glad to have the AMS electrons - (red circles) over increasing energy data, but says, "I'm not happy it cost $2 billion, not to m ention the cost of the ex tra levels, as measured by the AMS and compared p for ordinary cos ray collishuttle flight." The contr over sy a r ound AMS is sur e to continue. Hopefully, its find- swith .the exnectat.ion he positron fractmic increases ions (gree line) T ion ings will ultimately justify the expense. quickly above 8 GeV of energy. The increase
Sources: Physics Review; CERN Courier; NASA Science; MIT News.
indicates there must be new sources of positrons.

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December 2014

AAA Events on the Horizon
DECEMBER 2014
FRI, Dec 5 @ 6:15 pm Next: Jan 9 AAA Lecture at the American Museum of Natural History, M "How Many Earth-like planets are there in our Galaxy?" with NYU's David Hogg in the Kaufmann Theater. (Enter 77th St) FRI, Dec 5 @ 7 pm Columbia University Stargazing & Lecture at Pupin Hall, P "Holiday R eading f rom the Univ erse" Panel Discussion
(Observing at 7:30pm , C)

A Message from AAA President Marcelo Cabrera
Hello AAA Members, In November, 2014-2015 AAA's Lecture Series hosted David Gaynes, who discussed the making of his film Saving Hubble. The series will continue on December 3 with NYU's David Hogg presenting "How Many Earth like Planets are there in our Galaxy?" Find the schedule for all lectures at http://www.aaa.org/lectures1415. This month, Board Member Jason Kendall's AAA course "Introduction to Astronomy" finishes its six-week exploration of the critical elements of amateur astronomy. Be sure to look out for more classes from AAA in the future; tuition is always discounted for members. As we head into winter, there are still a few AAA observing sessions on the calendar. Dates, locations, and directions to the sites can be found at www.aaa.org/observing. The AAA calendar of events updates often, so be sure to check it frequently at www.aaa.org/calendar.

MON, Dec 8 @ 7:30 pm (See AAA Discount Below) AMNH Frontiers Lecture at the Hayden Planetarium, P "In S earch of the T rue Univ erse - The Tools, Shaping, and Cost of Cosmological Thought" with Ma r tin Ha r wit. The a wa r d-winning author discusses his new book, which looks at how our knowledge of the working universe and its evolution grew. (Enter 81st St) FRI, Dec 12 @ 7:30 - 9:30 pm Observing at Floyd Bennett Field - Brooklyn, PTC MON, Dec 15 @ 6:30 pm (See AAA Discount Below) AAA & AMNH Winter Skies Telescope Party at the Hayden Planetarium, PTC Join astronomers Steve Beyer, Joe Rao, and Ted Williams for a peak at the nebulae and open cluster that will be visible this winter and learn how to observe the night sky from inside the planetarium with its state-of-the-art Zeiss IX projector. Then, bundle up, grab a hot chocolate, and head outside to the Ross Terrace to observe celestial objects with the AAA. (Enter 81st St) TUES, Dec 30 @ 6:30 pm (See AAA Discount Below) AMNH Astronomy Live at the Hayden Planetarium, P "E arth , A s S een f rom S pace" with Ca r ter E mma r t, Dir ector of Astrovisualization at AMNH. Drift over the blue planet and witness the unparalleled beauty of the most diverse and necessary planetary system that we call home. See it faithfully visualized with satellite data accompanied by a live ambient soundscape. (Enter 81st St)
C: Cancelled if cloudy; M: Members only; P: Public event; T: Bring telescopes, binoculars.

Happy Holidays and Happy New Year!
Marcelo Cabrera President, AAA

The Amateur Astronomers' Association of New York
Info, E vents, and Obser ving: president@aaa. org or 2 12 -535-2922 Membership: members@aaa. org Eyepiece: editor@aaa.org

Visit us online at www.aaa.org. Around the AAA
OSIRIS/REx, NASA's first asteroid sample-return mission, is going to Bennu, and AAA Board Member Evan Schneider will be there! Rather, his name will -- thanks to a contest from the Planetary Society. Launching in 2016, the spacecraft will visit the asteroid 1999 RQ36, which very likely contains the same organic molecules that may have seeded life on our planet. Ironically, Bennu is potentially hazardous to life on Earth; it has a one-in-1,800 chance of impacting the planet in 2182. Studying the asteroid will be critical to helping future scientists prevent an impact. Meanwhile, studying Bennu's natural resources of water, organics, and precious metals could spur future space exploration and economic development for commercial space activities. OSIRIS/Rex will return to Earth in 2023, bringing asteroid samples and Evan's name NASA/Goddard/University of Arizona back with it. AM W Sources: planetary.org; asteroidmission.org.

For location & cancellation information visit www.aaa.org/calendar.

AAA Member Discount 2014 Hayden Events
American Museum of Natural History

Purchase at the Door - $12.00
(Regularly $15.00)

Good for Fr ont ier s L ect ur es, Astronomy Live, Telescope Parties, and other special events at the Hayden Planetarium.

To Reserve Tickets: 212-769-5200 ($2.00 reservation fee applies). This AAA coupon must be shown at the box office (81 st Street entrance).

Eyepiece Staff
December Issue

Editor in Chief: Amy M. Wagner
Copy Editor: Rich a r d Br ou n stein
Staff Writers: R ich ar d B r ou n st ein , T on y Fad d ou l, Joe Fedrick, Leo Genn, Stan Honda, Alan Rude, Evan B. Schneider Contributing Writers: M ar celo C ab r er a, R or i B ald ar i Administrative Support: J oe Delf au sse Printing made possible by McVicker & Higginbotham

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