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Journal of the Amateur Astronomers Association of New York October 2012
By Evan Schneider
MARS - NASA has embarked on its most ambitious journey, crossing the surface of Mars in search of microbial organisms, the stepping stone to life as we know it here on Earth. Scanning Gale Crater for organic compounds could one day lead to this historic discover y. It is "really a rover on steroids," said Colleen Hartman, assistant associate administrator for science at NASA. "It's an order of magnitude more capable than anything we have ever launched to any planet in the solar system." The "Red Planet," as it has been affectionately called, is a 2025 target for human exploration. Astronaut and astrophysicist John Grunsfeld, associate administrator for NASA's Science Mission Directorate, recently specified a potential 2033 manned mission to Mars, calling it "...a good year to launch to Mars just because of orbital mechanics." But there's more... Sending astronauts to the surface means developing protection against radiation, so Curiosity is also tasked with intricate measurements to gauge what scientists will need to engineer into environmental suits and human habitats. And let's not forget the weather. Although we won't be bringing umbrellas, the rover's weather station will measure temperature, wind and humidity. In all, Curiosity carries with it 10 science instruments with a total mass 15 times as large as the science payloads on Mars rovers Spirit and Opportunity. Some tools, like the laser fired instrument used to determine rocks' elemental composition at a distance, are the first of its kind on Mars. No mission would be complete without the prerequisite robotic arm, complete with drill and scoop, to gather soil, sample powdered rock interiors, and deliver them to the rover's analytical laboratory instruments. The Mars Reconnaissance Orbiter has identified clay and sulfite minerals in the lower layers of Gale Crater, indicating a wet past. Curiosity will confirm these assumptions firsthand. Getting started was a slow, calculated process. After traveling 352 million miles over an eight and a half month period, NASA engineers took a deep breath and started putting Curiosit y through its paces one at a time. Like an athlete stretching before a big race, equipment was turned on and exercised before moving forward across the terrain. And then it was time to go exploring. But "baby steps" was still the mandate. A first trip of 52 feet was ordered, and the rover carefully moved awa y from Bradbury Landing, named in honor of science fiction author Ray Bradbury. "This drive really begins our journey toward the first major driving destination, Glenelg, and it's nice to see some Martian soil on our wheels," said mission manager Arthur Amador of NASA's Jet Propulsion Laboratory (JPL). "The drive went beautifully, just as our rover planners designed it." Glenelg is a location where three t ypes of terrain intersect. Curiosity's science team chose it as a likely place t o find a first rock target for drilling and analysis. Several days later, it was time to deploy the robotic arm in the first of 6-10 consecutive da ys of planned activities to test the 7-foot arm and the tools it manipulates.
Mars Rover Curiosity- continued on Page 2

EYEPIECE

Volume 61 Number 10 ISSN 0146-7662

Mars Rover Curiosity Journeys On


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Mars Rover Curiosity - continued from Page 1

October 2012

The arm was put through a range of motions, placing it at important 'teach points' established during Earth testing, such as the positions for putting sample material into the inlet ports for analytical instrument. These activities are important to get a better understanding for how the arm functions after the long cruise to Mars and in the different temperature and gravity of Mars, compared to earlier testing on Earth.

M ars Reconnaissance Or biter watches over C uriosity , pinpointing its locations and target r esear ch areas
Photo Credit: NASA/JPL-Caltech/Univ. of Arizona

Despite billions of dollars and years of planning, operating the rover in an alien environment is still a challenging experience. "We're still learning how to use the rover. It's such a complex machine -- the learning curve is steep," said JPL's Joy Crisp, deputy project scientist for the MSL Project, which built and operates Curiosity. The rover performs differently when operating in the Martian atmosphere and gravity. Every da y is a new adventure. Each day, NASA releases updates on Curiosity's progress as it periodically moves down the 1,300 ft. path towards Glenelg, the natural intersection of three kinds of terrain, ideal for its investigative work. NASA feels that this area presents the rover with ample targets - terrain suitable for drilling, small craters that may represent older or harder surfaces, and an area similar to Bradbury Landing. After its scientific study of Glenelg, Curiosity will travel to the base of Mount Sharp.

Late NASA Press Release: Rover Finds Old Streambed on Martian Surface Sept 27 - PASADENA, Calif. -- NASA's Curiosity rove

r mission has found evidence of a stream that once ran vigorousl y across the area on Mars where the rover is driving. There is earlier evidence for the presence of water on Mars, but this evidence - images of rocks containing ancient streambed gravels - is the first of its kind. Scientists are studying the images of stones cemented 2

into a layer of conglomerate rock. The sizes and shapes of stones offer clues to the speed and distance of a long-ago stream's flow. "From the size of gravels it carried, we can interpret the water was moving about 3 feet per second, with a depth somewhere bet ween ankle and hip deep," said Curiosity science coinvestigator William Dietrich of the University of California, Berkeley. "Plenty of papers have been written about channels on Mars with many different hypotheses about the flows in them. This is the first time we're actually seeing water transported gravel on Mars. This is a transition from speculation about the size of streambed material to direct observation of it." The finding site lies between the north rim of Gale Crater and the base of Mount Sharp, a mountain inside the crater. Earlier imaging of the region from Mars orbit allows for additional interpretation of the gravel-bearing conglomerate. The imagery shows an alluvial fan of material washed down from the rim, streaked by many apparent channels, sitting uphill of the new finds. The rounded shape of some stones in the conglomerate indicates long-distance transport from above the rim, where a channel named Peace Vallis feeds into the alluvial fan. The abundance of channels in the fan between the rim and conglomerate suggests flows continued or repeated over a long time, not just once or for a few years. The discover y comes from examining two outcrops, called "Hottah" and "Link" with Curiosity's mast telephoto camera. Those observations followed up on earlier hints from another outcrop, which was exposed by thruster exhaust as Curiosity touched down on the Martian surface. "Hottah looks like someone jack-hammered up a slab of city sidewalk, but it's really a tilted block of an ancient streambed," said Mars Science Laboratory project scientist John Grotzinger of the California Institute of Technology in Pasadena. The gravels in conglomerates at both outcrops range in size from a grain of sand to a golf ball. Some are angular, but many are rounded. "The shapes tell you they were transported and the sizes tell you they couldn't be transported by wind. They were transported by water flow," said Curiosity science co-investigator Rebecca Williams of Tucson's Planetary Science Institute. The science team may use Curiosity to learn the elemental composition of the material, which holds the conglomerate together, revealing more characteristics of the wet environment that formed these deposits. The stones in the conglomerate provide a sampling from above the crater rim, so the team may also learn about the broader regional geology. The slope of Mount Sharp in Gale Crater remains the rover's main destination. Clay and sulfate minerals detected there from orbit can be good preservers of carbon -based organic chemicals that are potential ingredients for life. "A long-flowing stream can be a habitable environment," said Grotzinger. "It is not our top choice as an environment for preservation of organics, though. We're still going to Mount Sharp, but this is insurance that we have already found our first potentially habitable environment."


EYEPIECE

October 2012

WHAT'S UP IN THE SKY
AAA Observer's September Guide By Richard Rosenberg

Astronomical Fact of the Month

October's Evening Planets : There's very little excitement
this month. Mercury is in the evening sky early in the month, but is visible only with binoculars or telescopes. The same applies to Saturn. The only naked-eye planet is Mars, who's speedy movement keeps it from falling into the Sun.

October' s Evening Stars : The Summer Triangle (Cygnus,

Lyra and Aquila) are still brilliant. To the south are Scorpius and Sagittarius. Autumn constellations entering the scene i nclude Pegasus, Andromeda and Perseus to the north, and fainter Capricornus and Aquarius.

October's Morning Planets : Jupiter rises about 10 PM on

October 1st and 8 PM on Halloween. It's in Taurus. Venus is still prominent, rising three-and-a-half hours before the Sun on the first of the month and 3 hours at its end. On the third it will be less than one degree from the bright star (Regulus). Venus moves from Leo into Virgo on October 23. well up in the east. These center around Orion, the Great Hunter, and include Taurus the Bull, Auriga the Charioteer, Gemini the Twins, Canis Major the Large Dog and Canis Minor the Small Dog.

October's Morning Stars: The great constellations are now

Albert Einstein's general theory of relativity has led astronomers to now use gravitational lensing to look for dark matter and the imprint of dark energy, two of the greatest modern scientific mysteries. Dark energy, which acts in opposition to gravity, is the dominant force in the universe. "We can't see dark energy directly by any means, but we're looking for how it has sculpted the matter distribution of the universe over the past few billion years, since it's been the dominant factor, and also how it has affected the rate at which the universe is expanding," explained Dr. Evalyn Gates, Director of the Cleveland Museum of Natural History and author of "Einstein's Telescope" (W.W. Norton & Co., 2009, $25.95) Gravitational lensing is currently the only method astronomers have for tracing out the web of dark matter that pervades the universe, and determining how dark energy has impacted the evolution of this web. Like dark energy, dark matter is invisible. It accounts for most of the matter in the universe, but exactly what it is remains unknown. Scientists only know that dark matter differs significantly from normal matter that dominates everyda y life.
Nebula of the Month: Pencil (NGC2736)

October's "Skylights"
October 3 October 4 October 5 October 6 October 8 October 12 October 14 October 15 October 16 October 18 October 20 October 21 October 25 October 29 Venus less than 1 degree south of star Regulus Jupiter is stationary (beginning retrograde m o t i o n ) Jupiter is 5.7 degrees east of the Moon Mercury is 3 degrees f rom Saturn in the twilight sky. Binoculars or telescopes required Draconid meteors peek Last Quarter Moon at 3:33 a.m. (EDT) Venus is 6.5 degrees north of the Moon. The crescent Moon is v ery low 45 minutes bef ore sunrise New Moon at 8:03 a.m. (EDT) The crescent Moon is low in the west shortly af ter sunset Mars is 4.8 degrees southwest of the Moon Mars is 3.1 degrees north of Antares Orionid meteors peak First Quarter Moon at 11:32 p.m. (EDT) Saturn is in conjunction with the Sun, entering the morning sky Full Moon at 3:49 p.m. (EDT)

In Chile's high Atacama Desert, the European Southern Observator y's La Silla Observatory trains its Wide Field Imager on a distant nebula, 11,000 light -years away in the southern constellation Vela. The Pencil Nebula comes into view, its flowing hair -like filaments travelling through the interstellar medium at 403,000 mph. The nebula contains the remains of a centuries old colossal supernova explosi on that blasted gas and dust out in many directions.
The Vela supernova remnant is an expanding shell of gas that originated from the supernova explosion. Initially the shock wa ve was moving at millions of kilometers per hour, but as it expanded through space it plowed through the gas bet ween the stars, which has slowed it considerabl y and created strangely shaped folds of nebulosPhoto Credit: ESO ity. The Pencil Nebula is the brightest part of this huge shell. The nebula's luminous appearance comes f rom dense gas regions that have been struck by the supernov a shock wav e. As the shock wav e trav els through space, it rams into the interstellar material. At first, the gas was heated to millions of degrees, but it then subsequently cooled down and is st ill giving off the f aint glow that was captured in this extraordinary new image. 3

For additional information visit: www.aaa.org/month1210


EYEPIECE

October 2012

WHY WE EXPLORE

Spotlight on NASA Missions: Our Human Desire to Explore By Amy Wagner

"To reach for new heights and reveal the unknown, so that what we do and learn will benefit all humankind." The NASA Vision

The Year of the Solar System Comes to an End

October 2010 through August 2012 marked a period of an unprecedented flurry of launches, flybys, and orbital insertions which NASA dubs "The Year of the Solar System" (YSS) ­ a Martian year (23 months), that is. "History will remember the period...as a golden age of planetary exploration," says Jim Green, Director of Planetary Sci ence at NASA headquarters, "There hasn't been anything quite like it in the history of the Space Age." During YSS, Deep Impact/EPOXI and Stardust NExT studied the comets Hartley 2 and Tempel 1; the shoebox -size O/OREOS ("Organism/ORganic Exposure to Orbital Stresses") launched to perform experiments on the durabilit y of life in space, the experimental solar sail, NanoSail D, launched and created the first "solar sail flares," while MESSENGER began its orbit around Mercury. The second half of 2011 saw more activity than entire decades of the Space Age with Dawn's orbit around asteroid Vesta, spacecraft Juno beginning its journey to Jupiter, the launch of two GRAIL spacecraft to map the gravitational field of the Moon, and the launch of NASA's roving, nuclear-powered Mars Science Lab Curiosit y. In 2012, the Mars rover Opportunity completed an epic long distance run across the planet's surface, Dawn fired up its engines to depart Vesta for the dwarf planet Ceres, and New Horizons continued on its way to study Pluto and the Kuiper Belt, the birthplace of comets. YSS concluded in August with the challenging and successful landing of Curiosity on Mars, dubbed the "Seven Minutes of Terror." "So the end," says Green, "is just the beginning. These missions will keep us busy long after YSS is history." The NASA website "E yes on the Solar System" provides an engaging, interactive 3D tour of all the scientific spacecraft currently operating throughout our solar system - http:// eyes.nasa.gov/.
Solar Exploration at 50
This year is a milestone year for space exploration - more specifi cally, for NASA's missions in planetary science and its efforts to expand its presence across the solar syst em. Since the 1960s, NASA has broadened its reach with increasingl y sophisticated missions launched to a host of nearby planets, moons, comets and asteroids. This summer, NASA celebrated the 50th anniversary of its first successful planetary mission. Launched on August 27, 1962, Mariner 2 was sent on a flight to Venus (a month earlier, a range safet y officer blew up Mariner 1 five minutes into its flight when the spacecraft's rocket went off-course during launch). Mariner missions were designed to be the first U.S. spacecraft to visit other planets, specificall y Venus and Mars. Mariner 2 measured for the first time the solar wind ­ a constant stream of charged particles flowing outward from the Sun ­ and its infrared and microwave radiometers revealed that Venus has cool clouds and an extremely hot surface. Mariner 4

NA SA render ing of M ariner 2

2's signal was tracked until January 3, 1963, and the spacecraft remains in orbit today around the Sun. NASA's Science Mission Directorate (SMD) seeks to understand the origins, evolution, and destiny of the universe, and to understand the nature of the strange phenomena that shape it. SMD sponsors scientific research and develops/ deploys satellites and probes in collaboration with its international partners to answer fundamental questions. Of primary interest to the SMD Planetary Science Di vision is: "How do planets and life originate?" By focusing on the small bodies and objects in our inner and outer solar syst em, PSD is engaged in one of the oldest scientific pursuits of discover y. The stunning work of NASA's Planetary Science missions are revealing answers to questions about the origins of planets and minor bodies, the evolution of the solar system into its current diverse state, the evolution of life on Earth, and the possibility of life evol ving elsewhere in the solar system. Planetary exploration missions are conducted by some of the most sophisticated robots ever built, allowing scientists to extend their observations to the farthest reaches of the solar system and into remote and hostile environments.

Discovery at 15 ­ Dawn of the Asteroid Age
As a complement to its larger "flagship" planetary science missions, NASA created the Discover y Program in 1992. Its main objective - t o enhance our understanding of the solar system by exploring planets, their moons, and small bodies such as comets and asteroids. Discovery's goal is to launch many, smaller, cost-capped missions that use fewer resources and require shorter devel opment times. The program was a breakthrough in the wa y NASA explores space. For the first time, scientists and engineers were asked to design highly focused planetary science investigations that would deepen our knowledge about our solar system. Discover y was also among the first NASA programs to require education and outreach
Why We Explore - continued on Page 14


EYEPIECE

October 2012

"The 4% Universe" Reveals a Great Mystery of Science By Edward Fox

We may not be part of the Occupy Wall Street's "1%," but we and everything else in the observable universe are part of the "4%"­ you, me, every star, every planet ­ everything. The other 96% is unknown to us all ­ in fact, a mystery. Richard Panek tells the story of how scientists came to this conclusion and their hunt for this unknown in his book, The 4% Universe ­ Dark Matter, Dark Energy and the Race to Discover the Rest of Reality (Houghton Mifflin Harcourt, $26.00). A recipient of the Guggenheim fellowship in science writing, Panek tells the back-story of how scientists reached their conclusion after discovering that the universe is expanding and galaxies are spinning at unexplained rates. He sets the historic stage and presents the various interrelated stories of the key participants and the competing teams of scientists. There are stories of bitter rivalries ­ the physicists versus the astronomers ­ in the quest to solve this mystery. Panek describes team interrelationships ­ the collaborations and backbiting, in the quest for the answers, and glory that will fall to the winners ­ the coveted Noble Prize. The individuals and their personalities are the backbone of this story. Family circumstances and backgrounds provide a rich tapestry for understanding how they all became to be a part of this intense competition. Noted American astronomer Vera Rubin's childhood interest in astronomy was her start. The story takes the reader through her education, marriage and growing family, all while carrying out her life's work studying galaxies and their motion. Rubin's professional progression, including her published work and the reactions of her peers, provide an insight into how hard it is to lead the field in an uncharted area of science. When Rubin and her colleagues found that the rotational profiles of galaxies they studied could only be explained if the galaxies were surrounded by a massive halo of invisible matter, the discover y of dark matter could not be far behind. Her personal difficulties during pregnancy had Rubin routinel y squeezing through a tight passagewa y to get to her less than glamorous workspace. But motivation was ever prevalent, as witnessed by her tradition of mounting a picture of the Andromeda Galaxy, the subject of her early work on the galaxy's rotation, on her various office ceilings. The core of this story is about two competing teams trying to determine whether the universe would continue to expand for-

ever, or if the expansion would stop and the universe collapse upon itself in a Big Crunch. Supernova Cosmology Project and the High-z Team ("z" being astronomical shorthand for redshift) searched for supernovae in distant galaxies and used them to calibrate their distances. Both groups found that not only was the universe continuing to expand, but also that the expansion is accelerating. This expansion required a force ­ dark energy, as it is now known. Panek tells this very technical story in vivid descriptive detail. He does not have to rely on formulae, diagrams or pictures. It is a story that the lay person can understand. Unlike most myster y stories of fi ction or non -fiction, this story is not wrapped up in its final chapter, explaining everything in a neat package. According to Panek, "The astronomers who set out to write the final chapter in the history of the universe had to content themselves instead with a more modest conclusion: To be continued." I, for one, am looking forward to Panek's sequel in this mystery stor y of the universe! Eyepiece Staff - October Issue Editor Evan B. Schneider Writing Staff: Richard Brounstein, Joseph Fedrick, Ed Fox, Stan Honda, Amy Wagner Special Sections: Marcelo Cabrera, Joshua Erich, Edward Fox, Bernie Kleinman, Richard Rosenberg

AAA Members - Eyepiece Staff Openings
Interested in joining our growing team of AAA Eyepiece staff members? Enjoy researching, writing and editing? If so, we would like to hear from you. The world of astronomy is vast and amazing. Every day new discoveries bring scientists and astronomers closer to understanding the origins and composition of our universe. NASA/JPL, the European Space Agency, the Japanese Space Agency, ground -based telescope arrays around the world and in space, all of these entities and others challenge our minds. We need you to report their ground-breaking work to our members.

Come be a part of something out of this world... Evan B. Schneider, Editor Email me at: editor@aaa.org

Kleegor's Universe
By Joshua M. Eric h, www.pixelatedparchm ent.com

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EYEPIECE

October 2012

A Message from AAA President Marcelo Cabrera
Hello Members: It's going to get cold soon, so take advantage of our many AAA observing sessions around NYC. We have one more trip to North-South Lake scheduled for this month. Take advantage of the superb dark skies relatively close to the city. October brings us to the annual AAA Urban Starfest, our most popular stargazing event. Scopes and activity tables will be set up in Central Park's Sheep Meadow on Saturday, October 20 (rain date Sunday, October 21). Organized in conjunction with the NYC Urban Park Rangers, this year's honored guests include David Eicher (editor in chief) and Richard Talcott (senior editor) from Astronomy magazine, and Tele Vue founder and chief optical designer, Al Nagler. Joining the event as well will be Michael Peoples from Adorama Camera, a longtime friend and supporter of AAA. There will be free gifts, raffles, and special prizes (make sure you participate early and stay for the drawings). Don't miss David Eicher's special talk about the objects in the sky. It promises to be enlightening. For more details, visit the AAA website at www.aaa.org/starfest. Get ready for the start of our lecture series at the AMNH. We kick off on October 19 with Michael Paul from Penn State on "The Google Lunar X PRIZE: The Launch of Private Exploration of the Solar System." This season's schedule is available at www.aaa.org/lectures1213. Clear Skies!

Sincerely, Contacting AAA
Membership: members@aaa.org Eyepiece: editor@aaa.org General Club Matters and Observing: president@aaa.org

Marcelo Cabrera President, AAA

Telephone: 212-535-2922

Website: www.aaa.org

NASA to Teachers: Come Fly With Me Teachers from six NASA Explorer Sc

hools (NES) have been selected to receive the 2012 School Recognition Award for their contributions to science, technology, engineering and mathematics (STEM) education. The winners included the team from Mountview Road School, Morris Plains, N.J, which was featured in a November, 2011 Eyepiece article. In April, 2013, three teachers from each school will travel to NASA's Johnson Space Center. There they will have the opportunity to fl y aboard a reduced gravity aircraft and conduct experiments designed by their students. The experiments will examine the acceleration and inertia of objects, how fluids with different vi scosi ties behave in microg r a v i t y, and how the absence of gravity affects mass and
NA SA's two- engine tur bofan air craft C-9B ascends

Floating in zero gravity in the test ar ea

weight. "Congratulations to the NES teachers selected for this innovative NASA experience. The reduced gravity flights allow teachers to conduct scientific investigations in a microgravity environment, similar to how experiments are conducted on the ISS," said Cecelia Fletcher, acting program manager for primary and secondary education at NASA headquarters. "This experiential learning opportunity helps to spread the excitement of STEM education throughout the NASA Explorer School network." NASA reviewed many applications before selecting six schools for their exemplary classroom practices and innovative uses of NES resources to engage a broad school population. The schools were chosen from more than 470 registered participants in NES, the classroom -based gatewa y for students in grades 4-12 that focuses on stimulating STEM education using agency content and themes.

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EYEPIECE

October 2012

WHAT IF???

Robot Scientists
By Richard Brounstein

As I write this, I'm still so very proud of NASA days or light-weeks away. Even the speed of light becomes inconvenient for communication over distance. When we fifor their successful landing of the Mars Curiosity rover, exnally send a probe to another solar system, that probe will be ploring Gale Crater as you read this column. I don't know years out of communication without changing the physi cs of what rover will be our next visitor to Mars, but eventually we signal travel (worm hole, anyone?). Currently, there is no wa y hope to send human scientists to the Red Planet. We have to. for NASA to control such a mission, so their probes need to For all its advancements, Curiosity is still just a programmable get smart. robot with lots of tools - in a wa y, not much different than those employed in manufacturing plants. The equipment folWhat elements of reason must be instilled in a future lows carefull y planned instructions. The real "curiosity" and probe? It will need to follow the same logic as human explordecision making happens here on Earth, by humans. The misers. It needs to look at the big picture and decide what is most sion team tells it to look at the surrounding landscape. The y interesting to analyze. Then it needs to perform the analysis, direct it to a location and send commands to use a laser, drill, gather the results and provide a comprehensive report for misshovel, or whatever tools are needed to collect information and sion scientists, however long it takes to communicate. samples. When tests are run, earthbound scientists analyze the Consider a probe fl ying through a remote solar sysresults and decide its next steps. tem. It will need to set an efficient trajector y to perform a This may work well for probes on Mars, but someda y fl yby of each planet. It will know of most of the planets beour electronic ambassadors need to get smarter. They must fore it gets there, thanks to the extra-solar planet research bedecide how to run their own missions without micromanageing performed by powerful telescopes on Earth and in space, ment. Eventually, let's send a "Commander Data" (from Star but it will certainly discover several more planets and moons Trek: TNG) on exploration missions, and not a well -tooled that we can't see. The probe will need to calculate how to factor y worker. navigate to each new body and analyze them. We want the probe to determine Transporting humans to Mars if it is just some interesting rock like won't happen for many years, given the Earth's moon or if there might be liquid enormous problems that must be solved water on or under its surface. We want before positioning assets on the surface. it to be smart enough to modify its traBut putting astrogeol ogists on the planet jector y to do several fl ybys of that most could potentially accomplish in weeks interesting world(s) and acquire detailed what the combined efforts of Viking, photographs and other analyses with its Sojourner, Spirit, Opportunity and cameras and detectors. When this probe Phoenix have taken years to achieve. "phones home," it is sending to Earth Yes, in just a few weeks. the most useful results, just as if we sent So let's go there. They'll need an astronaut scientist on this journey. some mobile ground transportation, Rob nau R2 f s ort ­ is h next an geol ogical instruments, and a laboratory ous oobott,2d­ veloor dhhrough ta e pace genergtrioemdexter- While interstellar robotic exploration r e pe t S Act A e ent by may still be many years off, artificial (oh, also lots of coffee or full acclimaNASA and GM intelligence is much closer to reality. tion to the Martian Sol). Clearly, havWhile we are sending probes to within light-minutes of Earth, ing a human mind personally exploring a planet is far superior now is the time to make our probes smarter while we can still to remotely controlled equipment. monitor the quality of their work. Future probes to Mars or But will putting humans on an alien world always be other local worlds should not only go farther with better tools, the case? I hope not. There will always be places where we but will hopefull y be much smarter. We want the probe to cannot go, but machines can. High risk exposure to radiation, survey a site and then decide which features are the most interhostile deep space environments, and the sheer issue of a huesting. It should decide which rocks should be sampled and man lifespan vs. robotic l ongevity speak to the need for a senwhich experiments need to be run each sample. This is a great tient artificial intelligence in our space program. If past exwa y to test the intelligence of our robots and prepare us for the ploration is any indication of the future, robot explorers will time when they need to do more thinking on its own. one day travel to worlds farther and farther away from their Eventually, our intelligent robots ma y choose their human creators. They will need to get smarter to do their jobs. own landing sites and which experiments they should run. We Currently, most of our space probes are close enough even want our robot scientist to understand a concept such as to Earth for effective communication at the speed of light. But "organic life" and alien intelligence, so it knows t o get excited in the future, we will send probes t o distances where human if and when it stumbles on evidence of life. interaction will take weeks, months or even years ( Voyager I, Eventually, a future rover on Mars must not just be at the edge of our solar system, takes 16 light -hours to transmit). Imagine delays controlling a rover on Titan (2.6 light curious...but be a brilliant observer as well. hours roundtrip) or on Pluto (10.6 light -hours roundtrip). Richard Brouns tein's m onthly colum n, "WHAT I F," explores what today Probes in the Kuiper Belt or the Oort Cloud would be light seem s im probable or impossible. Stay tuned for m ore fascinating concepts.
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EYEPIECE

October 2012

AAA BRIEFS IN ASTRONOMY
NASA Sees the Light

With the combined power of NASA's Spitzer and Hubble space telescopes, as well as a cosmic magnification effect, astronomers have spotted what could be the most distant galaxy ever seen. Light from the young galaxy captured by the orbiting observatories first shone when our 13.7 -billionyear-old universe was just 500 million years old. Over time, the universe transitioned from a dark, starless expanse to a recognizable cosmos full of galaxies. The discover y of t his faint, small galaxy, MACS 1149-JD, opens a window onto the deepest, remotest epochs of cosmic history. "This galaxy is the most distant object we have ever observed with high confidence," said Wei Zheng, a principal research scientist in the department of ph ysics and astronomy at Johns Hopkins and lead author of a new paper appearing in Nature. "Future work involving this galaxy, as well as others like it that we hope to find, will allow us to study the universe's earliest objects and how the dark ages ended." Light from the primordial galaxy traveled approximately 13.2 billion light-years before reaching NASA's telescopes. Objects at these extreme distances are mostly beyond the detection sensitivity of t oda y's largest telescopes. To catch sight of these early, distant galaxies, astronomers rely on gravitational lensing. The gravity of foreground objects warps and magnifies the light from background objects. A massive galaxy cluster situated bet ween our galaxy and the newfound galaxy magnified the newfound galaxy' s light, brightening the remote object some 15 times and bringing it into view.

gy outbursts due to the occasional capture of a passing star or gas cloud. This is in marked contrast to the 'active' galaxies of the early universe filled with various star types. Quasars and radio galaxies are prime examples: owing to their bright, ex-

Artist impression (ESA/NA SA/RUG/M arcelZinger

M ACS 1149-JD, is shown her e in three levels of detail.

otic radiation, these can be observed as far as the edge of the observable universe. The light of normal stars in their galaxies is extremely faint at such distances. Active galaxies are detected through luminous radio, ultraviolet or X-ray radiation, resulting from steady accretion onto their massive central black holes. The fact that three objects, as well as many others, emit strong far -infrared radiation, it indicates that vigorous star formation is taking place, creating hundreds of stars per year and lasting millions of years. Bright radio emissions impl y strong, simultaneous black hole accretion. While black holes expand, the host galaxies are growing rapidly as well. Herschel observations provide an explanation: more massive galaxies have more massive black holes. Astronomers have observed this scaling relationship since the 1990s: the fireworks in the early universe could well be responsible for this relationship. According to Barthel, "It is becoming clear that active galaxies are not only among the largest, most distant, most powerful and most spectacular objects in the universe, but also among the most important objects; many if not all massive normal galaxies must also have gone through similar phases of simultaneous black hole-driven activity and star formation."

Ancient Galaxies - Better Mothers
axies in the early universe grew fast by rapidly making new stars. Such prodigious star formation episodes, characterized by the intense radiation of newborn stars, were often accompanied by extreme energy bursts caused by the massive central black hole accretion. The discover y was made by a group of astronomers led by Peter Barthel of the Kapteyn Institute in the Netherlands. Our Milky Wa y galaxy forms stars at a slow, steady pace. On average, one new star a year is born. Since the Milky Wa y contains about a hundred billion stars, the actual changes are slight. Ours is an extremely quiet galaxy; its central black hole is inactive, with only weak ener 8

Vesta's "Ring Around the Collar"

Gal

NASA's Dawn spacecraft has revealed that the giant asteroid Vesta has its own version of ring around the collar. Two new papers based on observations from the low-altitude mapping orbit of the Dawn mission show that volatile, or easily evaporated materials, have colored Vesta's surface in a broad swath around its equator. Pothole-like features mark some of the asteroid's surface where the volatiles, likely water, released from hydrated minerals boiled off. While Dawn did not find actual water ice at Vesta, there are signs of hydrated minerals delivered by meteorites and dust evident in the giant asteroid's chemistry and geology. The findings appear in the journal Science. Briefs - continued on Page 9


EYEPIECE

October 2012

AAA BRIEFS IN ASTRONOMY
Make it so, Number One

The biggest challenge in mounting a space mission to another star may not be technology, but people, experts say. Scientists, engineers, philosophers, psychologists and leaders in many other fields gathered in Houston last week for the 100 Year Starship Symposium, a meeting to discuss launching an interstellar voyage within 100 years. "It seems like it would be so hard, and the biggest obstacle is ourselves. Once we get out of our wa y, once we commit to this, then it's a done deal," said former "Star Trek: The Next Generation" actor LeVar Burton,

Starship USS Enterprise warps though space (Credit: P ar amount/Viacom)

who is serving on the advisory committee of the 100 Year Starship project. The initiative hopes to spur the development of new propulsion technologies, life support systems, starship and habitat designs, as well as m yriad other necessary innovations, to send a vehicle beyond our solar system - where no manmade object has yet traveled - and then to another star. As the closest stars to the Sun are still light -years awa y, such a feat will be daunting. "I think the greatest challenges are going to be what the greatest challenges in anything are, and that's the people piece," said former NASA astronaut Mae Jemison, the first African-American woman to travel to space. Jemison is heading the new 100 Year Starship organization, which was founded with seed money from the Defense Advanced Research Projects Agency (DARPA).

rocks, evidence of a wet environment on early Mars. Concretions result when minerals precipitate out of water to become hard masses inside sedimentary rocks. Many of the Kirkwood spheres are broken and eroded by the wind. Where wind has partially etched them away, a concentric structure is evident. Opportunity used the microscopic imager on its arm to look closel y at Kirkwood. Researchers checked the spheres' composition by using the Alpha Particle X-Ra y Spectrometer on Opportunity's arm. "They seem to be crunchy on the outside, and softer in the middle," Squyres said. "They are different in concentration. They are different in structure. They are different in composition. They are different in distribution. So, we have a wonderful geological puzzle in front of us. We have multiple working hypotheses, and we have no fa vorite hypothesis at this time. It's going to take a while to work this out, so the thing to do now is keep an open mind and let the rocks do the talking." Just past Kirkwood lies another science target area for Opportunity. The location is an extensive pale-toned outcrop in an area of Cape York where observations from orbit have detected signs of cla y minerals. That may be the rover's next study site. Four years ago, Opportunity departed Victoria Crater, which it had investigated for two years, to reach different types of geol ogical evidence at the rim of the much larger Endeavour Crater. "The rover is in very good health, considering its 8-1/2 years of hard work on the surface of Mars," said Mars Exploration Rover Project Manager John Callas of NASA's Jet Propulsion Lab. "Energy production levels are comparable to what they were a full Martian year ago, and we are looking forward to productive spring and summer seasons of exploration."

Crunchy on the Outside - Soft in the Middle

NASA's long-lived rover Opportunity has returned a puzzling image of the Martian surface. Spherical objects concentrated at an outcrop called Kirkwood on the western rim of Endeavour Crater differ in several wa ys from iron rich spherules nicknamed "blueberries" the rover found at its landing site in early 2004. "This is one of the most extraordinary pictures from the whole mission," said principal investigator Steve Squyres of Cornell University. "Kirkwood is chock full of a dense accumulation of these small spherical objects. Of course, we immediately thought of the blueberries, but this is something different. We never have seen such a dense accumulation of spherules in a rock outcrop on Mars." The spheres measure as much as one-eighth of an inch in diameter. The analysis is still preliminary, but indicates that these spheres do not have the high iron content of Martian blueberries. Blueberries found elsewhere by Opportunity are concretions formed by action of mineral -laden water inside

Using its Microscopic Im ager, Opportunity p hotographed these small spheric al objects about 2.4 inches across at an outcrop called " Kirkwood" at the Ende avor Crater

A Word From the WISE

NASA's Wide-field Infrared Survey Explorer has led to a bonanza of newfound supermassive black holes and extreme dust-obscured galaxies (hot DOGs). Images from the telescope revealed millions of dust y black hole candidates across the universe and 1,000 even dustier objects thought to be among the brightest galaxies ever found. "WISE has exposed a menagerie of hidden objects," said Hashima Hasan, WISE program scientist at NASA headquarters. "We've found an asteroid dancing ahead of Earth in its orbit, the coldest starlike orbs known and now, supermassive black holes and galaxies hiding behind cloaks of dust." Briefs - continued on Page 10
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EYEPIECE

October 2012

AAA BRIEFS IN ASTRONOMY
Time for the Big Lens Watch the Gas

Eight billion years ago, rays of light from distant galaxies began their long journey to Earth. That ancient starlight has now found its wa y to a mountaintop in Chile, where the newl y-constructed Dark Energy Camera, the most powerful sky-mapping machine ever created, has captured and recorded it for the first time. That light may hold within it the answer to one of the biggest mysteries in physics - why the expansion of the universe is speeding up. Scientists in the international Dark Energy Survey collaboration announced this week that the Dark Energy Camera, the product of eight years of planning and construction by scientists, engineers, and technicians on three continents, has achieved "first light." The first pictures of the southern sky were taken by the 570-megapixel camera on Sept. 12. "The achievement of first light through the Dark Energy Camera begins a significant new era in our exploration of the cosmic frontier," said James Siegrist, associate director of science for high energy physics with the U.S. Department of Energy (DOE). "The results of this survey will bring us closer to understanding the myster y of dark energy, and what it means for the universe." The Dark Energy Camera was constructed at the DOE Fermi National Accelerator Laboratory in Batavia, Illinois, and mounted on the Victor M. Blanco telescope at the National Science Foundation's Cerro Tololo Inter American Observatory in Chile, which is the southern branch of the U.S. National Optical Astronomy Observator y. With this device, roughly the size of a phone booth, astronomers and

Combining the cutting-edge capabilities of the Atacama Large Millimeter/submillimeter Array telescope (ALMA) with newl y-devel oped laboratory techniques, scientists are opening a completely new era for deciphering the chemistry of the universe. A research team demonstrated their breakthrough using ALMA data from observations of the gas in a star-forming region in the constellation Orion. Using new

Plot of radio emission at numer ous frequencies from t he molecule ethyl cyanide (CH3CH 2C N). Blue at bottom is the plot from t errestrial laboratory measur ement; red at top is the plot from ALM A observation of a star-for ming r egion in the constellation Orion. The ability to do this type of matching r epr esents a major br eakthrough for studying the chemistr y of the Universe. Plot s ar e superimposed on H ubble Space Telescope image of t he Orion Nebula; small box indicates location of area observed with A LM A.

Zoomed-in image fr om the Dar k Ener gy C amer a of the Fornax cluster of galaxies, w hich lies about 60 million light year s from Earth. (Credit: Dar k Energy Survey Collaboration

physicists will probe the m yster y of dark energy, the force the y believe is causing the universe to expand faster and faster.

Dragon Approaches the ISS
ASA managers, SpaceX officials and international partners announced an Oct 7 launch date for the first contracted cargo resupply flight to the ISS. Program managers confirmed that the Falcon 9 rocket and its Dragon cargo spacecraft are space-ready, and that the ISS was prepared to receive the capsule. Dragon's launch will be the first of 12 contracted resupply flights and will include 1,000 pounds of supplies and critical materials to support the 166 investigations planned for the station's Expedition 33 crew. Dragon will return734 pounds of scientific materials, and 504 pounds of space station hardware. 10

technology both at the telescope and in the laboratory, the scientists were able to greatly improve and speed the process of identifying the "fingerprints" of chemicals in the cosmos, enabling studies that until now would have been either impossible or prohibitively time-consuming. "We've shown that, with ALMA, we're going to be able to do real chemical analysis of the gaseous 'nurseries' where new stars and planets are forming, unrestricted by many of the limitations we've had in the past," said Anthony Remijan of Virginia's National Radio Astronomy Observatory. ALMA is under construction on the Atacama Desert of northern Chile, at an elevation of 16,500 feet. When completed in 2013, its 66 high -precision antennas and advanced electronics will provide scientists with unprecedented capabilities to explore the universe as seen at wavelengths between longer -wavelength radio and infrared.

N

What's Nu(STAR) With You?

Sept 21 marked 100 days since NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) launched into space. The telescope is making first observations of black holes, super-dense dead stars and glowing remains of exploded stars. It has the longest mast of any astronomical telescope ever launched. The 33-foot flexible structure allows NuSTAR to focus high-energy X-rays into sharp images for the first time. Joint observations with Chandra and Swift telescopes allow astronomers to interpret data more precisely, and gain a better overall understanding extreme events in the cosmos.


EYEPIECE

October 2012

FOCUS ON THE UNIVERSE "Earthshine" Captured on Camera
By Stan Honda
he next time you see a crescent Moon, look cl osel y at our natural satellite. You'll see the brightly lit crescent and the rest of the orb faintly lit up in a ghostly light. What is this phenomenon, known as the "ashen glow" or the "old moon in the new moon's arms"? It's called "earthshine," when sunlight is reflected off the Earth, hits the night side of the moon and reflects back to Earth. If you were on the night side of the moon in this crescent phase, you'd see a full Earth in your night sky. Earthshine can be seen really well through binoculars when the crescent is very thin. And it can be photographed easily from any location, in the city or under dark skies. The days after a new Moon are the most convenient for most shooters because the Moon is up in the evening hours. For those who are awake before dawn, the waning crescent rises early in the days before the new Moon. Like many objects in the sky, the Moon often looks best when combined with a natural landscape or cityscape. If you go out about an hour or so before setting, you'll have time to see how it dips down and aligns with something on the horizon. Since the Moon, even in its crescent phase, is quite bright, you won't have to worry about cit y lights overpowering it. Being by far the brightest object in the night sky, it's not difficult to get nice photos. There are many places in New York City t o find an interesting foreground. For clear views to the west, the reservoir in Central Park (from the east side), the High Line, Long Island City in Queens and the Brookl yn Promenade all have great angles of the Manhattan skyline. For early risers, views t o the east include Liberty State Park, Jersey City, Hoboken and Weehawken, all in New Jersey. From Carl Schurz Park, one of the AAA observing sites, you get a nice view to the east of Queens, the Triboro Bridge and an Amtrak bridge. A good tripod and your camera are all you really need. Focal lengths from medium to telephoto work best (about 50mm to 200mm). With the telephoto lenses, you'll have to wait until the Moon is closer to the horizon or take a vertical shot to include the Moon and a foreground object. Compose by putting the Moon above or between buildings in a citysca pe, above or next to a landscape if you're in the countryside. With toda y's lenses, you could proba bl y take a few photos with a medium focal length when the Moon is about 20 degrees or so above the horizon and zoom to l onger focal lengths as it gets closer to the horizon. Then you'll have a variety of compositions to choose from. For best quality, set the ISO low, at 200. The exposure will vary depending on the ambient light and what is in the frame of your camera. The picture shown here was taken over a bentonite clay hill in the Petrified Forest National Park just over an hour after sunset. I used a zoom lens set at 200mm on a Nikon D700; this photo has been cropped from the original, so the Moon looks pretty big relative to the landscape. At ISO 200, the exposure was 4 seconds at f5.6. It was shot one day after the new Moon, a perfect time to see earthshine.

T

I used a shutter release on a cable so the camera won't shake. If you use the self-timer built into many cameras, you can avoid vibrations that will ruin your shot. Set the selftimer for 4-5 seconds, if you can adjust it, then when you press the shutter release any vibrations of the camera will dampen down. One thing to keep in mind is that you'll be overexposing the lighted crescent part of the moon by quite a bit to be able to see the earthshine. This generally doesn't matter since the crescent is so thin. The correct exposure will often also be the correct one for cit y buildings in twilight or at nightfall.

Stan's earthshine over a clay hill (Petrified For est, 2012)

Don't underexpose the Moon or you won't see the earthshine. With digital cameras you can try different settings and check on the camera screen to see what works best. Try positioning the Moon near a tree in the distance; this often works well for both horizontal and vertical compositions. Make sure the lens is not too wide angle, use a medium setting (about 35mm or more on most digital SLR cameras) and back up to include the whole tree or object in your picture - or zoom in on just the Moon and a few branches. The crescent phase looks good in photographs taken after sunset or before sunrise when there is a glow of color on the horizon. The sky will be a deep blue and the features in the earthshine portion of the Moon might take on this same color. You'll also get some detail in the foreground objects that will add to the picture. Isaac Asimov, who observed the Moon from his Manhattan balcony, remarked after an early morning sighting, "I found myself marveling at Earth's good fortune in having a Moon so large and so beautiful."
Stan Ho nda is an accomplished professional contributing writer. In this continui ng series of art extensive knowledge of photographic equipment and Please visit www.stanhonda.com or submit questions to stanhonda@gmail.com. photographer and icles, he shares his techniques. your photography

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EYEPIECE

October 2012

One Member's Opinion No, I'm Not Going
By Bernie Kleinman

I am proud to think of myself as an amateur astronomer. I plan to keep my feet on the ground, and my mind attentive to realities as long as possible. But, there has been a proliferation of articles and news reports lately, including those here in Eyepiece, that discuss the serious possibility of colonization by humans on locations off our Earth. With some misgivings about playing the Devil's Advocate, I must point out some important reasons for not getting too excited about that whole thing. There are three main general objections, any one of which should, in my mind, shut down the entire idea of human life on Mars, the Moon, asteroids or elsewhere. The first, which repeatedly gets downplayed, is the near impossibility of overcoming the many physical problems. We humans have evolved here on Earth and have real needs that are uniquely met by this Earth. We all cherish our lives, or we should. Perhaps the need for extraterrestrial water might be resolved, so let me give you that. But there has been no serious suggestions about the lack of air to breathe, of the enormous temperature changes that occur, of the gravity problems, of the deadly radiation, of the way to provide for good, varied foods, for fuel, and lastly the need for power, power, and more power. Solar? Hah! And I have not mentioned the means of getting any of us, with our supplies, to this new place in the sky. Secondly, and even more important if that is possible, is that no one really wants to go there, wherever "there" is. I cannot think that any sensible person would choose to put his or her life at serious risk in order to live the remainder of it on a place that is unimaginabl y hostile. Of course there are the true adventurers who must try anything, because that is who they are. Good luck to them. Nor is there any real foreseeable need to do so. We have vast areas here on Earth that are almost totally unpopulated. If worst came to worst, we could far more easily col onize the Antarctic, where there is gravity, oxygen water, soil, and everything else. Warm clothing doesn't sound like much of a problem. The presumed conditions that prompt talk of a future need for living elsewhere can be solved much more easily here than by packing our bags. We have always done so. If reall y bad things lay in the distant future, things that we cannot control, then... too bad for Mankind - it will be in the cards, we will say goodbye, and that's that. I do hope that all of the above does not make me out to be an unworthy amateur astronomer. I am very much in favor of spending lots of bucks on unmanned missions and on the great new astronomy projects that are now on the boards and into the future.
Members: If you would like to express your opinions, please send your email to editor@aaa.org for publishing consideration. EBS, Editor

to the planetary frontier. The New Horizons spacecraft is now halfwa y bet ween Earth and Pluto, on approach for a dramatic flight past the icy planet and its moons in July 2015. After 10 years and more than three billion miles, on a historic voyage that has already taken it over the storms and around the moons of Jupiter, New Horizons will shed light on new kinds of worlds we' ve only just discovered on the outskirts of the solar system. Pluto gets closer by the day as the mission travels across our solar system, just the fifth probe t o traverse interplanetary space so far from the Sun, and the first to travel so far, to reach a new planet for exploration. Already the fastest spacecraft

Pluto-Bound New Horizons In 2006, NASA dispatched an ambassador

Artist rendering of NASA's Ne w Horizons spacecraft

ever launched, a 2006 flyby of Jupiter early in the mission provided a 9,000 mph boost to its speed, taking the craft to over 50,000 mph. While New Horizons is planned as a fl yby mission of Pluto, and not an orbiter, an intensive science campaign would begin five months before closest approach and end two months after. The spacecraft carries seven instruments to fulfill its scientific objectives. These instruments are provided by six institutions, and are supported by a world-class science team. After the Pluto­Charon encounter, in an extended mission phase, the spacecraft would proceed to rendezvous with at least one, and as many as three Kuiper Belt Objects. The recent discover y of another moon around Pluto is exciting news for planetary science, but it's also likely causing some anxiety for the team in charge of New Horizons. In July, researchers using NASA's Hubble Space Telescope announced the detection of P5, a tiny moon measuring just 6 to 15 miles across. P5 brings Pluto's known satellite tall y to five, and it comes just a year after Hubble spotted moon number four, the similarly diminutive P4. These two recent discoveries show that the Pluto system is more crowded than scientists had thought, so NASA's New Horizons spacecraft may have to watch its step.

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EYEPIECE

October 2012

AAA Urban Starfest 2012
Saturday October 20, 2012*
(from dusk to 10:00 p.m.)

Central Park's Sheep Meadow
The AAA Urban Starfest
is free and open to everyone. It demonstrates the ability and perseverance of a mateur astronomers and the general public to view the wonders of the night sky, even though we will be only a mile from Times Square! The Sheep Meadow is an open area, free of glare from local lighting, wher e almost the entir e sky can be seen. Many club members and other amateur astronomers bring telescopes --some fairly large--so that they and the public can share the heavenly views.

Meet Honored Guests: The AAA Urban Starfest
David Eicher, Editor, Astronomy Magazine Richard Talcott, Sr Editor, Astronomy Magazine Al Nagler ­ Televue Optics founder Mike Peoples - Adorama

strives to plant new seeds of curiosity (much like NASA has planted its Curiosity rover on Mars) -- not just about astronomy, but about science, technology, engineering, and math. The supportive environment of this Central Park event is the perfect venue to meet helpful and friendly people dedicated to sharing what they've learned. Although observing the night sky is the focus of the evening, Starfest is about making new friends and talking to people about new and amazing things.

Have a Fun Time!!! Free raffles
13mm Nagler eyepiece (donated by Televue Optics)

Limited edition AAA T-shirts Free giveaways Lots of telescopes to see the stars

*Rain date Sunday, Oct 21 For more details, visit www.aaa.org/starfest
AAA's First "Star Fest" -1995

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EYEPIECE

October 2012

Why We Explore - continued from Page 4

plans that would communicate the excitement and understanding of space exploration to students and the public. This September, the Discover y Program's Dawn mission saw its fifth anniversary and experienced a major achievement: for the first time in history, a spacecraft orbiting one alien world broke orbit to explore another body. Dawn was launched on September 27, 2007, beginning its 3-billion mile odyssey through the inner solar system, to explore the two most massive objects in the main asteroid belt between Mars and Jupiter. In July 2011, it reached its first stop, Vesta. Three months later, Dawn successfull y left the giant asteroid for a 2015 encounter with the dwarf planet Ceres. Dawn is the first Discovery mission to be powered by i on propulsion, which uses electricity to i onize xenon to generate thrust that can be maintained for months at a time. The hyper -efficient sol ar electric ion thrusters enable Dawn to carry enough fuel to adjust its velocit y to orbit and study t wo planetary bodies on a single voyage. Dawn is a mission of firsts: the first to orbit a main belt asteroid; the first to orbit two targets; and the first spacecraft to visit a dwarf planet. Its goal is to characterize the conditions and processes in place at the formation of our solar system by investigating two of its largest protoplanets: Vesta and Ceres. Accreted during the first few million years of development, these minor planets have remained intact since their formations, each following a very different evolutionary path. To carry out its scientific mission, the Dawn spacecraft carries three science instruments: a visible camera, a visible and infrared mapping spectrometer, and a gamma ray and neutron spectrometer. Radiometric and optical navigation data will provide information relating to the gravity field and thus, the bulk properties and internal structure of the two bodi es. Dawn will measure mass, shape, volume, and spin state, record their elemental and mineral compositions, determine their tectonic and thermal history, magnetism, and core size, and examine their internal structures. The most important question that the mission addresses is the role of size and water content in determining Vest a, as mapped by D awn. The south pole the evolution of reveals a mountain mor e than twice the planets. height of M ount Ever est (NAS A/JPL image) The massive asteroid Vesta is an evolved, dry, differentiated object that shows signs of resurfacing. It resembles the rocky bodies of the inner solar system, including Earth. By contrast, the nearly spherical dwarf planet Ceres has a primitive surface rich in water ice, and appears to have many similarities to the large icy moons of the outer solar system. Uniquely, Vesta may have rocks that are more strongly mag14

netized than on Mars, and Ceres may have seasonal polar caps of water frost, and a thin, permanent atmosphere, distinguishing it from the other minor planets. In September, two separate papers by Dawn mission scientists described the presence of volatile (easily evaporated) materials on Vesta, which were released from minerals likel y containing water. These volatiles have col ored the Vesta's surface around its equator. While Dawn did not find actual water ice at Vesta, it found evidence of h ydrated minerals that were delivered there by carbon -rich meteorites that collided slowl y enough to preserve their volatile content. Pitted terrain on the giant asteroid was formed where the volatiles boiled off. "The pits look just like features seen on Mars, and while water was common on Mars, it was t otally unexpected on Vesta in these high abundances," said Brett Denevi of Johns Hopkins University, author of one of the papers. Dawn's orbit provided close-up views of Vesta, revealing unprecedented detail about the giant asteroid. The mission revealed that Vesta completely melted in the past, forming a layered body with an iron core. The spacecraft also revealed the scarring from titanic collisions Vesta suffered in its southern hemisphere, surviving not one but two colossal impacts in the last two billion years. Without Dawn, scientists would not have known about the dramatic troughs sculpted around Vesta, which are ripples from the two south polar impacts. "We went to Vesta to fill in the blanks of our knowledge about the early history of our solar system," said Christopher Russell, Dawn's principal investigator, based at the University of California Los Angeles (UCLA). "Dawn has filled in those pages, and more, revealing to us how special Vesta is as a survivor from the earliest days of the solar system. We can now sa y with certainty that Vesta resembles a small planet more closel y than a typical asteroid." In further pursuit of asteroids, NASA announced in August a new Discover y-class mission, OSIRIS-REx, as part of the New Frontiers Program. New Frontiers takes on specific solar system exploration goals identified as top priorities by consensus of the planetary science community. Due t o launch in September, 2016, OSIRIS-REx ("Origins-Spectral Interpretation-Resource Identification -Security-Regolith Explorer") will be the first U.S. mission to fl y to an asteroid and bring back samples from it. The spacecraft will travel to the asteroid designated 1999 RQ36. Once it arrives at the asteroid in 2019, OSIRIS-REx will begin comprehensive surface mapping, choose a location from where it will take a sample, and extend its robotic arm to collect more than two ounces of material for return to Earth in 2023. Approximately 1,900 feet in diameter, the asteroid, which has altered little over time, will offer a snapshot of our solar system's infancy. Organic molecules have been found in meteorite and comet samples, indicating some of life's ingredients can be created in space, and scientists want to see i f they also are present on RQ36; the asteroid is likely rich in carbon. With a cost of less than $700 million, OSIRIS-REx, and missions like it, demonstrate an evolution of U.S. space exploration toward cost-effective, highly efficient, and safe programming that will sustain scientific goals and financial health of NASA into the next 50 years of solar system exploration.


EYEPIECE

October 2012

AAA Events on the Horizon
October 2012
Tuesdays, October 2, 9, 16, 23, 30 8:30 - 10:30 p.m., P, T, C Observing on the High Line, Manhattan/Enter at 14th Street Next dates: Tuesdays in Spring, 2013 Saturday, October 13 8 p.m. - 1:30 a.m., P,T,C Observing at North-South Lake, Haines Falls, NY Next date: Spring, 2013 Saturday, October 20 Dusk - 10:30 p.m., P,T,C (Rain date Oct 21) AAA Urban Starfest Observing at Central Park, Sheep Meadow Saturday, October 20 7:30 - 11 p.m., P, T, C Observing at Great Kills Gateway National Park Staten Island Next date: November 17 Friday, October 19 7:30 - 11 p.m., P, T, C Observing at Floyd Bennett Field, Brooklyn/ 50 Aviator Road Next date: November 30 Friday, October 26 7:00 - 11 p.m., P, T, C Observing in Carl Schurz Park, Manhattan/ East End Ave & 86th Next date: Spring 2013 Saturday, October 27 10 a.m. - noon, P, T, C Solar observing in Central Park, At the Conservatory Water Next date: November 17
Legend for Events: M: Members; T: Bring te lescopes, binoculars, etc. P: Ope n to t he public C: Cancelled if cloudy For the latest information about all AAA events, visit www.aaa.org

Saturn Sinks Into the West Jupiter Rises Higher in the East
By Joe Fedrick

The morning of August 13 was clear enough so that I could see Mercury, Venus, and Jupiter in the east-northeast. Mercury was still a crescent phase in my 60mm refractor at 100x while Venus was still not quite at dichotomy. Jupiter displayed the so-called "reversal" of its cloud belts as discussed in the October issue of Sky and Telescope magazine. Actually, it appeared to me that the North Equatorial Belt was still narrow, but had joined up with a dark, wide, temperate zone belt to create an apparently ver y wide new North Equatorial Belt. Saturn and Mars joined up with Spica in Virgo the Virgin to my southwest on the evening of August 13. I did not observer these planets telescopically, but used a pair of 7x50 binoculars to observe the grouping so that I could enjoy the col or contrast with a nearly topaz-yellow Saturn joining a coral pink Mars and sapphire-blue Spica, all fitting together in the field of view. I might have considered joining with AAA observing team at the High Line to observe the spectacle on Tuesday, August 14, but skies were overcast. In fact, I have not done quite so much observing as I might have liked to due to the frequently overcast, murky skies this summer. This doesn't stop me from repeatedly trying, though. NEXT MONTH IN EYEPIECE
Our Look Ahead to November: Tony Hoffma n reports on the newly discovered Comet ISON that will be visible in daylight in 2013; Amy Wagner's continued new journey: "Why We Explore;" exa mines NASAs ma ny missions; Stan Honda opens up his photographic world to us in his " Focus on the Universe" series; Richard Brounstein presents a unique perspective in his "What If" column; Alan Rude brings us " Gravity Waves a nd LIGO:" "Kleegor's Universe" explores the funny side of astronomy; Ed Fox's AAA Briefs in Astr onomy bring the universe to us; Rich Rosenberg's "What's Up in the Sky" points our scopes in the right direction, plus Nebula of the Month, Astr onomical Fact of the Month....and more!!!

AAA 2012/2013 Lecture Series Calendar
The AAA is proud to present an astronomy lecture series from October through May each year. Members and the public are welcome to attend. Admission is free, and no reservations or tickets are required. Lectures are held at the Kaufmann Theater of the American Museum of Natural History, Central Park West between 77th and 81st streets (use the 77th Street entrance). Lectures begin at 6:15 p.m. and run to 8:00 p.m.
Oct 19 Michael Paul - Penn State - "The Google Lunar X Prize - The Launch of Private Exploration of the Solar System" Timothy Creamer - NASA Astronaut Corps. - "Where We've Come From, Where We Are, Where We're Going" David Sobel - Author - "A More Perfect Heaven" Jerry Bonnell - NASA - "Astronomy Picture of the Day" David Hogg - NYU - "The Sloan Atlas of Galaxies" Shane Larson - USU - "Whispers From the Cosmos: The Dawn of Gravitational Wave Astronomy" Andrew Kessler - Author - "Robot Arms, Cowboy Spacemen and my 90 Days With the Phoenix Mars Mission" National Technical Institute for the Deaf at RIT Astrodance at CUNY Graduate Center

Nov 9 Dec 7 Jan 4 Feb 1 Mar 1 Apr 5

AAA ONLINE STORE IS NOW OPEN
AAA Presents: A new and exciting wide selection of logo merchandise for our members to purchase online

"Shop the Stars" www.aaa.org/store
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Amateur Astronomers Association PO Box 150253 Brooklyn, NY 11215 ADDRESS SERVICE REQUESTED

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