Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://www.aaa.org/EyepieceFiles/aaa/2015_07_July_Eyepiece.pdf Äàòà èçìåíåíèÿ: Mon Jul 6 22:11:43 2015 Äàòà èíäåêñèðîâàíèÿ: Sun Apr 10 03:38:55 2016 Êîäèðîâêà: Ïîèñêîâûå ñëîâà: charon

NASA/James McDivitt

NASA celebrated 50 years of spacewalks on June 3. In 1965, Gemini 4 astronaut Ed W hite, seen here, became the first American to walk in space.

Journal of the Amateur Astronomers Association of New York
July 2015 V
olume 64 Number 7; ISSN 0146-7662

Come Sail Away with Me: The Launch of the LightSail
FOR THE LOVE OF LIFTOFF By Stanley Fertig On May 20, the Planetary Society's LightSail successfully launched into orbit, and I was fortunate to be among the Society's guests attending that day at Cape Canaveral. LightSail represents nothing less than a revolution in space exploration. It is the first satellite financed entirely by the public at large. The Society received donations directly and through a crowdfunding campaign organized by Brooklyn's own K ick starter. It blasted past its initial target in one day and rapidly surpassed even the most fervent believers' expectations: over $500,000 donated by over 10,000 individuals in less than a week! LightSail also represents an exciting alternative to conventional chemical propulsion, with a promise of faster, cheaper space travel in the future. It's exactly what it sounds like: a spacecraft with a sail propelled by light from the Sun. Think of the great sailing ships of the 16th centuJosh Spradling/The Planetary Society ry explorers that used wind to Artist's image of Lightsail in orbit. tack their way across oceans to discover new lands ­ now imagine sailing spaceships pushed by the Sun across the Solar System to explore other worlds. LightSail gives new meaning to solar w ind. "A lthough photons hav e no m ass, they nev ertheless can impart a small bit of momentum to an object they strike ," explained Jason Davis of the Planetary Society. This surprising property of light was first discovered by James Clark Maxwell in 1865. While the push is extremely gentle ­ for LightSail it's about the weight of a fly sitting on your hand! ­ the force is continuous. In frictionless space, with a large enough sail, an object can accelerate gradually to great speeds. The main advantage of solar sailing is that the Sun provides the fuel for free. Of course, a huge amount of chemical fuel is still needed for liftoff from the Earth's surface by rocket, but a traditional spacecraft must carry additional propellant to be able to accelerate out of orbit and make course changes on route to a
LightSail Launch (cont'd on Page 5)

A Pluto Primer as New Horizons Homes in on the Icy Dwarf
AAA ASTRO ANSWERS By Amy Wagner For the first time, humans will get a close-up view of an icy dwarf planet in our outer Solar System. W h en NASA's New Horizons spacecraft reaches Pluto this month, after a 9 1/2-year and 2.8 billion-mile journey, we will finally be able to study a type of object never examined before. NASA/JPL A highly pixilated image of Pluto "T his is a v ery ex citing tim e f or from May taken by New Horizons planetary science," sa id AAA's from 50 million miles away. Jaclyn Avidon, who presented at a special Astro Answers event on May 8 entitled "N ew Horizons: Exploring Pluto." She likened New Hor izons to the Apollo 11 lunar landing in 1969 ­ a major "first" in the exploration of our Solar System. The celestial bodies found in our Solar System can be divided into three groups fanning out from the Sun: rocky planets (including asteroids and rocky dwarfs, like Ceres and Vesta), gas giants, and icy dwarfs. In the 1960s and 1970s, humans began exploring the first two groups, but up until now, icy dwarfs have gone unexamined. NASA and its university partner, Johns Hopkins Applied Physics Laboratory, along with Southwest Research Institute, hope to accomplish several goals with the New Horizons mission. They seek to map Pluto's surface, understand its geology and morphology, study its atmosphere, measure its temperature, and image the moons of the Pluto-Charon system. NASA/JPL Pluto and its largest A close-up of Jupiter's Great Red Spot moon share a center of taken by Voyager 1 in 1979 from 5 million gravity that lies between miles away. Scientists hope New Horizons the two bodies, so they will give us as detailed an image of Pluto.
Astro Answers (cont'd on Page 6)

THIS MONTH: O b ser v ing at Nor t h-South Lake Jul 18/19 & Astronomy Night at the Intrepid Jul 24


July 2015

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

Naked-eye Stargazing in NYC
With so much to see in New York City, you may not realize how much there is to see abov e it. Despite the glow of its bright lights, there's plenty to view in New York's night sky without the aid of equipment. On a clear night, you can find 20-30 objects shining above the Big Apple. Here is a list of some of those objects you can see with the naked eye. Big and Bright The Moon: The brightest object in our night sky, only tall buildings can hide it. Planets: After the Moon, Venus, Jupiter, Mars, and Mercury are the next brightest objects. Saturn is also very bright with only a few stars more luminous. Planets are often mistaken for stars, but you'll notice they don't twinkle. Much closer to Earth, their lights shine steady without the same interference of our atmosphere which distorts starlight. Points of Light Stars and Constellations: Sirius tops the list as the brightest star viewed from Earth. Other bright stars include Arcturus, Vega, Capella, Spica, Antares, Betelgeuse, Rigel, Deneb, and Altair. In city skies, the shape-forming stars of constellations Orion and Ursa Major (Big Dipper) can easily be seen. Smudges and Spots Galaxies: Our nearest neighbor, Andromeda, is 2.5 million light-years away ­ a tiny bit of haze in only the darkest areas. Nebulae: The Orion Nebula (M42) can be seen as misty spot below Orion's Belt in that constellation. Star Clusters: The Pleiades cluster contains over a thousand stars. It is a haze of light in our city sky, but in darker places the brightest six of the "Seven Sisters" can be picked out. On the Move Comets: Halley and Hale-Bopp are large, nearby comets that were visible to the naked eye when they appeared in the 80s and 90s, but they won't be back for a while. Meteors and fireballs: In New York, shooting stars dart across the sky. But city dwellers see barely a quarter of the number spotted upstate during a meteor shower. Satellites: Many of the thousands of artificial satellites that orbit Earth are visible, like the International Space Station. Slower than a meteor, it takes 5 minutes to cross the sky. Now for some urban observing tips. A v oid lam pposts. Move even a few yards away, and there's a drastic difference. B e patient. As your eyes get used to the dark, more objects will appear. Head to the riv ers. Get a wider view at the city's edges with the buildings out of the way. Observ e with AAA! Check the club's ca lenda r for sta r ga zing sessions at locations throughout the boroughs of NYC.
Follow veteran sky watcher Tony Faddoul each month, as he points our minds and our scopes toward the night sky.

July's Evening Planets: Bight Venus and Jupiter can
be found under Leo the Lion until 10 PM, setting earlier every night until 9 PM at the end of July. Neptune will be in Aquarius the Water Bearer as of midnight, rising earlier every night until 9PM at the end of the month. Uranus can be found in Pisces, rising one hour after Neptune. Find Saturn in Libra the Scales and dwarf planet Pluto in Sagittarius the Archer all night.

July's Evening Stars: Spot the Summer Triangle of
Vega in Lyra the Harp, Deneb in Cygnus the Swan, and Altair in Aquila the Eagle all night. See Spica in Virgo the Virgin, Antares in Scorpius the Scorpion, and Arcturus in BoÆtes the Herdsman. Also find the stars of constellations Cassiopeia, Cepheus, Draco, Virgo, Sagittarius, Libra, Hercules, Ophiuchus, and the two Dippers throughout the month.

July's Morning Planets: Saturn is up between Scorpius the Scorpion and Libra the Scales until 4 AM, setting earlier each morning until 1 AM at the end of July. Uranus rises in Pisces one hour after Neptune in Aquarius the Water Bearer at 12 AM. Mars rises in Gemini the Twins at 5 AM every day with Mercury there in the first half of July. Dwarf planet Pluto is in Sagittarius the Archer until sunrise.

July's Morning Stars: Find the Summer Triangle of
Vega in Lyra the Harp, Deneb in Cygnus the Swan, and Altair in Aquila the Eagle. Look for Capella in Auriga the Charioteer, Aldebaran in Taurus the Bull, along with the stars of constellations Lyra, Hercules, Sagittarius, Aquarius, Capricornus, Pisces, Aries, Draco, Pegasus, Cassiopeia, Cepheus, Andromeda, Draco, and the two Dippers.

July "Skylights"
Jul 1 Jul 5 Jul 6 Jul 8 Jul 15 Jul 18 Jul 21 Jul 23 Jul 24 Jul 26 Jul 26 Jul 31 Full Moon at 10:20 PM Moon at perigee (228,100 miles from Earth) Earth at aphelion, farthest from Sun in 2015 Last Quarter Moon at 4:25 PM New Moon at 9:25 PM Venus 0.5° north of the Moon (sunset) Moon at apogee (251,500 miles from Earth) Venus stationary First Quarter Moon at 12:05 AM Saturn 2° north of the Moon (pre-dawn) Uranus stationary Full Moon at 6:20 AM
Times given in EDT.

2


July 2015

Seen In Space
Spitzer Makes a Far Out Microlensing Discovery In April, NASA's Spitzer Space Telescope discovered one of the farthest exoplanets from Earth in our galaxy at 13,000 light-years away. L ess t h a n 1% of t h e M ilk y Way's 1,852 confirmed exoplanets are that far, with the farthest about 25,000 light-years from Earth. Spitzer found the new gas giant, with help from the ground -based Polish Optical Gravitational Lensing Experiment (OGLE) , using the microlensing technique. W hen one star passes in front of another, its gravity can act as a lens to magnify and intensify the light of the star behind it. If the foreground star has a planet, it will cause a blip in the light. OGLE is searching for planets toward the center of our galaxy, where star crossing is more common. Ground telescopes have found about 30 exoplanets with microlensing, but their distances can't be pinpointed. When a space telescope observes the same microlensing event from its vantage, then two sets of measurements can be used to calculate the planet's distance, or parallax. " S pitz er is the first space telescope to make a microlens parallax measurement for a planet,"sa id lea d a uthor J ennifer Yee, " ground... based telescopes are not as effective at such great distances ." Spitzer is in Earth-trailing orbit around the Sun, drifting 1/10 AU behind each year. It's about 128 million miles from Earth right now. Spitzer saw the microlensing 20 days before OGLE. Usually, NASA/JPL-Caltech the time-delay to Spitzer found an exoplanet toward our galaxy's ready a second center, one of the furthest away discovered. telescope takes too long to catch microlensing, because they are short -lived events. Fortunately, this one lasted for 150 days. Calculating the distance, scientists then determined the new planet's mass. Thanks to Spitzer, scientists can find and characterize far away exoplanets and ultimately learn how they're distributed throughout our galaxy. AM W Sources: spitzer.caltech.edu.

Also Seen in Space
WISE Finds the Brightest Galaxy in the Universe NASA's Wide-field Infrared Survey Explorer (WISE) mission ended almost five years ago, but its data continues to astonish ­ in May, scientists announced finding the brightest known galaxy. WISE conducted an infrared survey of the entire sky in 2010. (R enam ed N EOW IS E, it imaged near-Earth objects before its 2011 decommission; observations resumed in 2013.) WISE has revealed a new class of objects called ELIRGs, ex- NASA/JPL-Caltech tremely luminous Artist's concept of the brightest galaxy in infrared galaxies, our universe, WISE J224607.57-052635.0. found in the distant universe and undetectable in visible light. There are about 20 of these most luminous galaxies, and WISE J224607.57-052635.0 is the brightest yet. 12.5 billion light-years away, the light from a quasar at its giant black hole shines 300 trillion times brighter than the Sun. Although smaller than our Milky Way, the galaxy generates 10,000 times more energy. "This dazzling light may be from the main growth spurt of the galaxy's black hole," said Chao-Wei Tsai of NASA. Supermassive black holes are common at galactic centers, but it is rare to find one so far back in time. How did it get so big when the universe was still so young? "How do you get an elephant?"a sked P eter Eisenha r dt, pr oject scientist for WISE. "One w ay is start w ith a baby elephant." Perhaps, it was just born big. Another explanation is a voracious appetite. The pressure of radiating light pushes gas away from a black hole, limiting its consumption ­ and while it is possible to overcome that, this black hole would have had to break the limit over and over to become so enormous. Or perhaps, it pushes the limit during a long binge ­ if it isn't moving too fast. If a black hole spins slowly enough, it repels less food, and it can gorge itself for longer. "It's lik e w inning a hot-dog -eating contest lasting hundreds of millions of years," sa id co -author Andrew Blain. AM W Source: nasa.gov.

Out of This World
Boeing and Space X Race to Restore American Crew Launches In May, NASA placed an order with Boeing for a crew mission to the International Space Station, and another order is on the way for rival SpaceX. T h e U.S. sp a ce a gen cy is p it t in g t h e comp a n ies a ga in st each other for a 2017 slot to be the first crew launch by America since the Space Shuttle program ended. Since 2011, U.S. astronauts have had to use Russian Soyuz to get to the ISS. NASA's Commercial Crew Program NASA has enlisted private companies to restore human spaceflight capability to the U.S. A standard mission would Boeing's CST-100. carry four astronauts, but Boeing's CST-100 can hold up to seven. "It also w ill giv e us crew return capability ...letting us com plete a backlog of hands-on critical research that has been building up," sa id ISS chief scientist J ulie Robinson. SpaceX's Dragon has hauled cargo to and from the ISS since 2012, and a modified Crew Dragon completed a key flight test in May. But if program funding is not approved for 2016, certification for either capsule will be delayed, extending reliance on Russian crew vessels. Yet, the U.S. is also dependent on Russian rocket engines ­ and so is one of the competitors. Boeing and Lockheed Martin form the United Launch Alliance (ULA), which uses Russian engines in Atlas rockets for U.S. defense launches. ULA has a monopoly over the launches and supported a Pentagon request to ease the U.S. ban on the engines imposed following Russia's annexation of Crimea. Meanwhile, SpaceX's Falcon 9 rocket just received certification from the Air Force. The ban was lifted in June, SpaceX so SpaceX will not take over the monopoly, and Russian rockets remain. AM W Sources: nasa.gov; nytimes.com. Crew Dragon. 3


July 2015

Eyeing the Inside
FOCUS ON THE UNIVERSE By Stan Honda We've all looked t hr ough a telescope, but have you ever wondered what it's like to be insid e a telescope? I n April, I had the unique pleasure of walking through the tube of the McMath-Pierce Solar Telescope at Kitt Peak, near Tucson, Arizona. The visit was part of a weeklong trip I took with Ken Spencer, President of the Astronomical Society of Long Island. We joined friends Mike Terenzoni, who works at Kitt Peak's 90" telescope, and Dean Ketelson, a former Kitt Peak employee now at University of Arizona's Mirror Lab. First up that week, Dean arranged a tour of the Large Binocular Telescope (LBT) on Mount Graham, a three-hour drive from Tucson. Daytime temperatures were in the 90s in the city, but we took winter clothes, because the LBT sits atop a 10,700-ft. mountain, where it can be 40°F and colder. The LBT offered a great view from above its twin mirrors, and we were permitted to take pictures inside the dome that night while two astronomers conducted observations.

Stan Honda

Looking up the tube of the McMath-Pierce Solar Telescope.

Stan Honda

The Large Binocular Telescope on Mount Graham in AZ.

The LBT isn't just large, it's huge! It has tw o 8.4-meter mirrors, each ranking as the second-largest optical telescope in the world. The dome is cube-shaped, and separate doors open for each mirror, leaving a skeletal structure visible while observing. I could barely fit it all into frame for a picture. I selected a Nikon 16mm fisheye mounted on a Sony a7S camera; the a7S has an extremely high ISO setting, making it great for night photography. Several companies make adapters to use Canon, Nikon, or Leica lenses on the a7 models. I own a Novoflex, which is very sturdy. I tried to position myself as far into a corner as possible to get the scope and the dome in one shot. Motors whirred as the scope repositioned itself throughout the evening. To move in azimuth, the whole dome rotates. Standing on the floor, we couldn't feel the movement. Later, I noticed star trails in one of my photos, though I had taken short exposures. I was confused, until Dean pointed out that w e were the ones moving, not the stars. I set my camera at 12,800 ISO to record the faint light hitting the scope. As darkness fell, the stars shone brightly through the dome openings. My best exposures were 15 sec., f2.8. I was able to capture the telescope and keep the stars sharp with the short shutter speed. We returned to Tucson at 2:30 AM ­ the start to a week of sleep deprivation ­ and later that morning we headed to 4

Kitt Peak for a tour of the McMath-Pierce with solar astronomer Matt Penn. I was fortunate to meet Matt at the Northeast Astro-Imaging Conference earlier that month. He generously offered the tour, when I mentioned my upcoming trip. We started in the McMath-Pierce observing lab. The Sun's image is directed toward the instruments, and an operator has to wear sunglasses. Then, we entered the telescope tube itself ­ a bizarre notion indeed. At 400 ft., it's the longest in the world. The structure is permanently inclined at 32 degrees to match the observatory's latitude. Inside, the walls are diagonal; anyone working long hours there leaves feeling disoriented. Halfway along, we looked up to see heliostats reflecting the solar image down the tube. At the top, we were treated to a panoramic view of all the Kitt Peak observatories. It was too windy to set up our scopes that night, so we tried the 20" telescope at the Kitt Peak Visitor Center. It was wondrous to see star clusters, galaxies, and other objects through that large aperture scope. Ken and I attempted some long-exposure, hand-held photos of the open dome, scope, and night sky, supporting our cameras on chairs or on our knees and turning up the ISO to get short shutter speeds. Finally, I gave in and set up my small tripod to take a few more relaxed shots. Over the next few days, we attended a talk by astroimager Adam Block at the Mount Lemmon Observatory near Tucson, and Ken and I drove to the dark skies of Cave Creek Canyon in southeast Arizona for binocular observing and photography. By the end of the trip, we finally caught up on our sleep ­ rested Stan Honda and ready to reflect on a wondrous Red lights illuminate the dome of the 20" telescope at week of astronomy adventures.
the Kitt Peak visitor center.

Explore night sky photography at

www.stanhonda.com
Submit your photography questions to

stanhonda@gmail.com.

Stan Honda is a professional photographer. Formerly with Agence France-Presse, Stan covered the Space Shuttle program. In his "Focus on the Universe" column, he shares his night sky images and explores his passions for astronomy and photography.


July 2015 LightSail Launch (cont'd from page 1)

AAA Around Town
Stargazing at the World Science Festival in May In May, AAA joined the World Science Festival (WSF) for an evening of astronomy and a day of solar observing. Saturday, May 30 was an Greg Kessler event-filled night AAA Member Bart Fried with his antique brass at Brooklyn refractor at the World Science Festival's Night Bridge Park with Lights, Big City event on May 30. various talks about space. NASA astronauts Lee Morin and Nicole Scott were on hand to answer questions, and AAA's own Irene Pease took to the stage with Emily Rice from A stronom y on Tap to pla y a ga me ca lled " Ea r th or Other Wor lds." AAA members also came out in force to set up telescopes along the Pier 1 waterfront. The view of the Manhattan skyline was spectacular, but the real attractions were Jupiter, Venus, Saturn, and the Moon. Hundreds of people filled the park, patiently waiting in long lines to see the great celestial sights, while AAA's Susan Andreoli handed out red glow sticks to the kids. This was my fourth year observing for the annual WSF N ight L ights, B ig City event, which is extremely dedicated to making it easy to bring a telescope. Parking is free, and the WSF staff will help you unload your equipment and even bring it down to the waterfront for you. WSF really supports observers and makes them feel special. I'm already looking forward to next year! The next day, WSF held its Ultim ate S cience S treet Fair, and AAA was back for solar observing fun. Washington Square Park was filled with tents sporting all sorts of science themes with hands-on activities, demonstrations, and interactive experiments. The AAA tent was abuzz with activity too: UV bracelet-making for kids, raffles for four telescope prizes, and the fan favorite--a mini Martian rover demo by AAA's "Jupiter" Joe Martinez. AAA President Marcelo Cabrera set up the club's brand new Lundt solar telescopes, treating people to fantastic views of the Sun in H-Alpha light. If you think the only place to get a sun tan is the beach, think again! AAA member volunteers also distributed promotional materials and spoke to people about the many great ways that AAA brings astronomy to the public. It was a wonderful day, and the rain held off for most of it, so we all felt pretty lucky. Rori Baldari Rori Baldari
AAA President Marcelo Cabrera observing at WSF's Ultimate Science Street Fair on May 31.

destination. Not only is the extra fuel itself expensive, but it requires a larger, heavier, and costlier vessel to hold it. LightSail's spacecraft is only the size of a loaf of bread. Of course, this mini spacecraft (made of three stacked 10cm3 experimental satellites called CubeSats) comes wrapped in a vast sail that unfurls to 32 square meters. The sail is constructed of four triangular pieces of Mylar that form a square. Astoundingly thin yet strong, the material is only 5 microns thick, about the diameter of a red blood cell. In 1976, Carl Sagan, a co-founder of the Planetary Society, proposed solar sailing in an interview on Johnny Carson's Tonight Show. Almost for ty yea r s la ter , his dr ea m is now realized with Lightsail, which hitched a free ride to orbit from NASA aboard an Atlas V rocket. But, it won't be doing any sailing. This mission is designed simply to test equipment, electronics, and communications. After it drifts away from other CubeSats launched, its sail will unfurl. Shortly thereafter, drag will pull Lightsail toward Earth to meet a fiery end in the Earth's atmosphere. All will be over in a matter of weeks.

Stanley Fertig

AAA's Stanley Fertig witnessed the launch of the Planetary Society's LightSail at Cape Canaveral on March 20.

The night before launch, Society members gathered for dinner in anticipation of the event. This would be the second attempt to send up a solar sail. Ten years ago, the first one perished aboard a Russian rocket that failed to achieve orbit. On the morning of May 20, we sat together in the Florida heat in bleachers at the Kennedy Space Center, listening to prelaunch checks: "X sy stem : Go!" "Y sy stem : Go!" We had all seen this scene in A pollo 13 and countless other films, but there's nothing like being there ­ a real launch is thrilling! However, we weren't very close to the action. There was a good distance between the rockets and onlookers "in case anything goes wrong," a s a NASA spokesper son wr yly put it. The last ten seconds of countdown began, an orange flame appeared below the rocket, and then liftoff! The rocket rose, accelerating incredibly fast. Less than a minute later, it was out of view in the mist above the horizon, far from the cheers of the crowd crying out, "Go L ightS ail!" Lightsail's 25-day mission ended on June 15 when it burned up in the Earth's atmosphere. Although the spacecraft ran into several technical problems, its mission is considered a success. The vessel proved spaceworthy and it was able to deploy its sail. Another Lightsail model will launch in late 2016 aboard a SpaceX Falcon rocket to a higher orbit, where it will finally use photon-powered propulsion and fly! 5


July 2015 Astro Answers (cont'd from page 1)

orbit each other as a binary, unique in our Solar System. Together, their size is less than that of the continental U.S. The other four known moons were only discovered in the past ten years--Nix and Hydra in 2005, Kerberos in 2011, and Styx in 2012--so there could be more out there for New Horizons to find. Pluto itself was discovered in 1930 by Clyde William Tombaugh at the Lowell Vince Bly Observatory in Flagstaff, AriAtop an Atlas V rocket, New zona. Founder Percival LowHorizons launched with the fastest speed ever at over 36,000 ell began a search in 1906, ten mph in January 2006. years before his death, for a "Planet X," which he believed was responsible for discrepancies in the observed orbits of Uranus and Neptune. In 1978, when Charon was discovered and Pluto's mass could be determined, astronomers realized the system's gravitational effects were negligible on those gas giants. In fact, the discrepancies were due to an error in the calculation of Neptune's mass. Pluto was considered to be the ninth planet in our Solar System when discovered, but in 2006 it was reclassified as a dwarf planet. The International Astronomical Union then defined a planet as a body that orbits a star, is spherical in shape, and clears the neighborhood around its orbit. In binary with Charon, Pluto does not meet the last criterion --but a new "dwarf planet" category was created for it. On July 14, New Horizons will come closest to Pluto at only 7,750 miles away. Images will pick up surface features as small as 200 feet across. The icy dwarf's atmosphere is thin enough for its surface to be visible. However, scientists are anxious for the probe to get there as soon as possible, while there's enough of an atmosphere to study at all. Pluto's atmosphere comes and goes. The icy dwarf's orbit is very elliptical, bringing it closer to and farther away from the Sun at various points. Since 1989, Pluto has been moving away from the Sun, and as it does, it will lose its atmosphere. Pluto has a rocky core with a ­387°F surface of mostly nitrogen ice, along with methane and carbon monoxide ices. Closer to the Sun, the ices thaw and vaporize into a gaseous atmosphere. In a sort of "anti-greenhouse effect," also unique to our Solar System, Pluto cools itself down by this evaporation. These atmospheric gases then tend to escape into space, because Pluto's low mass does not have enough gravity to keep its clouds together. Farther from the Sun, the gases solidify and fall back down to the surface, freezing as ice. Scientists also want to arrive in time to see as much of Pluto-Charon as we can. Just as Earth's poles spend half a year in daylight and half a year in night, parts of the double planet can be shadowed in "arctic night" for decades at a time (one Plutonian year lasts 248 Earth years). The timing of the mission is critical to be able to map as much as possible. The $300 million New Horizons is the fastest spacecraft 6

ever launched. With the quickest launch speed ever at about 36,000 mph in January 2006, New Horizons then received a gravity-assist at Jupiter in 2007 to slingshot it to a current speed of about 51,000 mph on its path to Pluto. It will slow down to 30,800 mph to grab pics of Pluto during the flyby this month, but its data won't be downloaded for another 9 months. After that, the data will still need to be analyzed, so it could be a year or so before we learn anything from the probe. Once finished with its departure phase from Pluto -Charon in 2016, the New Horizon's science team hopes to extend the mission for a flyby of a distant Kuiper Belt Object (KBO) in 2018 or 2019. A candidate KBO will be selected soon, and the probe will fire its engines this fall to reach the target. However, funding for an extended mission has not yet been granted, so we may never get to see it. But the probe itself is destined to keep going; it will continue on forever. Whether or not New Horizons gets to study a KBO, it will finally help us fill in the gaps about icy dwarfs and propel exploration out to the furthest reaches of our Solar System, and beyond.

AAA Around Town
Stargazing at OutdoorFest in May AAA members rallied to bring the night sky within reach to spirited attendees at the opening of New York's annual OutdoorFest on May 29. Now in its second year, OutdoorFest, aims to connect urban OutdoorFest dwellers with an AAA hosted an observing session at the awareness and appreci- 2nd annual OutdoorFest's 5K Headlamp Trail Run and Campout on May 29. ation for nature and outdoor adventure. Sarah Knapp, founder of the ten -day festival, asked AAA to return this year with an observing session at the opening event, the 5K Headlamp Trail Run and Campout at the Henry Kauffman Campgrounds in Staten Island. I was joined there by AAA Members Joe DiNapoli, Otto Chin, Rich Dewar, and Siyu Tu, along with friends Nina Shankar and Charlie Ridgway. Each volunteered their time, equipment, and unique enthusiasm for the night sky with the OutdoorFest participants. Visitors included runners, campers, event staff, and vendors. Through a hazy sky with thin, cirrus clouds, we aimed six scopes at Solar System objects that spanned the ecliptic from the west to east: Venus in Gemini, Jupiter in Cancer, the Moon in Virgo, and Saturn in Libra. Bright stars and constellations were traced out with fingertips, and a partial 22° lunar halo could be seen. At the end of the night, we packed our scopes into dewdampened bags and chatted in the open field, surrounded by trees and rolling hills. We amused each other with stories about our observing experiences before making our merry ways home around midnight. AAA's participation in OutdoorFest gave us a wonderful opportunity to enjoy the special gratification that observing offers with fellowship and the joy of a shared interest in astronomy. Peter Tagatac


July 2015

Hubble Hubbub
Moon Madness at Pluto As if in anticipation of New Horizons' arrival at Pluto, Hubble has produced strange new data about the dwarf planet's weird and wild moons. I n J u n e, H u b b le revealed that Nix and Hydra tumble willy -nilly in their orbits at the Pluto-Charon system. Pluto and its largest moon, Charon, share a center of gravity lying between the two bodies, so they form a binary as a "double-planet." The gravitational field of the double-planet shifts, causing the other moons to wobble. Nix and Hydra are also shaped like footballs, which exaggerates the effect. "It's not just a little bit chaotic," said study author Mark Showalter. "N ix can f lip its entire pole. It could actually be possible to spend a day on Nix in which the sun rises in the east and sets in the north." P luto's other two moons, Styx and Kerberos, likely wobble too. Extrasolar planets have been discovered orbiting binary stars, and the Pluto moon dance demonstrates how such exoplanets might behave. "W e are learning chaos m ay be a com m on trait of binary systems," sa id co-author Doug Hamilton. Meanwhile, Hubble revealed that the orbits of Nix, Hydra, and Styx are locked in resonance; there is a precise ratio to their orbital periods. All five moons may have been in resonance at one time. Hubble also showed that Kerberos is much darker than its comrades. Scientists believe the system formed during a collision of Pluto and another body. Is it possible that charcoal-black Kerberos is a remnant of the invader? "Pluto w ill continue to surprise us when New Horizons flies past it in July," sa id Showa lter . "Our w ork w ith the Hubble telescope just gives us NASA/ESA/M. Showalter (SETI)/G. Bacon (STScI) a foretaste of what's in The orientation of Pluto's moon Nix AM W changes unpredictably as it orbits the store."
"double planet" Pluto-Charon.

Celestial Selection of the Month
Polar Ring Galaxy NGC 4650A Two galaxies for the price of one! Ab ou t 130 million light-years away in the constellation Centaurus lies the peculiar polar-ring galaxy NGC 4650A. A rare type of galaxy , it has a ring of stars, gas, and dust that orbits nearly perpendicular to its main, inner disk. Astronomers believe it acquired the ring during a collision with a neighbor galaxy at least a billion years ago. Only about 100 polar-ring galaxies have been discovered so far. Most seem to occur at lenticular galaxies, otherwise known as S0s ­ a transition state between spiral and elliptical galaxies. Viewed edge-on, S0s are shaped like spiral galaxies with a disk surrounding a bright, central, spherical bulge. But, they do not have arms or very much interstellar material. Viewed face-on, they can be mistaken for smooth, featureless elliptical galaxies. And like ellipticals, S0s consist primarily of old, red stars that formed AURA/STScl/NASA/ESA The unique shape of early in the life of the galaxy. S0s do polar ring galaxy NGC not produce new stars in any significant 4650A can be used to quantity; however, 4650A's younger, calculate dark matter. polar ring does have active star forming regions. These unique, multigenerational objects are helping astronomers understand one of the most mysterious aspects of galaxy structure. From the observed motions of its older inner disk and its younger polar ring, astronomers have determined that the ring of NGC 4650A is rotating faster than it should ­ too fast to be held together by only the stars we can see. An additional invisible source of gravity ­ dark matter ­ must be present. They are then able to estimate both the amount and shape of the dark matter in the galaxy. AM W
Sources: apod.nasa.gov; spacetelescope.org; wiki..

Sources: nasa.gov; nytimes.com.

Telescope of the Month
Sliding Spring Observatory in Australia On the dark, cloudless Mount Woorut near the town of Coonabarabran in New South Wales, Australia, sits the largest telescope on that continent ­ the 3.9m Anglo-Australian Telescope (AAT) ­ one of nine active telescopes at the Sliding Spring Observatory (SSO) . Operated by the Australian Astronomical Observatory, the AAT simultaneously observes hundreds of galaxies, collecting data for the 2degree-field Galaxy Redshift Survey. The SSO site itself is owned by Australian National University (ANU), which hosts the AAT, along with telescopes from the UK, Sweden, Poland, Korea, and several international collaborations, as well as ANU's own 2.3m Advanced Technology Telescope. It is also Julia Karrer home to ANU's SkyMapper, a state-of-the-art, automated wide-field telescope, which is conducting the first comprehensive digital survey of the entire southern sky. With its 1.35m modified Cassegrain optics The Skymapper telescope at Sliding Spring Observatory. and f4.79 focal ratio, SkyMapper can view to a sensitivity of one million times fainter than the human eye. Its 268 million-pixel digital camera captures a different region every 20 seconds to image every part of the southern sky 36 times over 5 years. Able to detect changes over time, it can discover large dwarf planets in the outer solar system and trac k asteroids. Astronomers also hope to use SkyMapper data to map the invisible dark matter of the Milky Way galaxy, using samples of rare stars, and to find the first quasars and stars that formed in our universe. In addition to surveys, SSO telescopes imag e gammaray bursts, search for transiting Hot Jupiter exoplanets, and look for extrasolar planets orbiting binary stars via the eclip se timing method. SSO is also home to the southern hemisphere station of iTelescope.Net, a global network of robotic telescopes design ed for amateur astronomers and astrophotographers. Members of the public can remotely access the telescopes from anywhere around the world through the internet at http://www.itelescope.net/. AM W Source: rsaa.anu.edu.au; wiki. 7


July 2015

AAA Events on the Horizon
FRI, July 3 @ 7:30 pm ­ 11 pm Next: Every Friday & Saturday Night AAA Observing at Lincoln Center Plaza ­ Manhattan, PTC SAT, July 4 @ 7:30 pm ­ 11 pm Every Friday & Saturday Night AAA Observing at Lincoln Center Plaza ­ Manhattan, PTC @ 9 pm ­ 11 pm Next: Aug 1 AAA Observing at Brooklyn Museum Plaza ­ Brooklyn, PTC TUES, July 7 @ 7:30 pm ­ 11 pm Every Tuesday Night AAA Observing at the High Line ­ Manhattan, PTC THURS, July 9 @ 7:30 pm ­ 11 pm Every Thursday Night AAA Observing at Brooklyn Bridge Park ­ Brooklyn, PTC SAT, July 13 @ 7:00 pm AMNH Special Presentation at the Hayden Planetarium, P
"M anhattanhenge" with Jackie Faherty. The setting sun will align perfectly with Manhattan's East-West numbered streets tonight, creating a cinema-worthy photo opportunity. Learn about the history and astronomy behind this fascinating phenomenon. (Enter 81 St)
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A Message from the AAA President
Dear AAA Members, Summer weather and summer skies make for great observing! Dates are now set for dark sky observing at North -South Lake. The next AAA trip to this premier location is on July 18. Check out http://www.aaa.org/north-south-lake/ for more details. If you would like to receive planning information about AAA trips to North-South Lake and Ward Pound Ridge, email me at president@aaa.org to be added to the Dark Skies Google Group. Again this year, the Rockland Astronomy Club has extended a generous invitation to join its Summer Star Party with a 20% discount on registration for AAA Members. The 10 -day event in the beautiful Berkshire Mountains runs from August 7-16. See offer details at http://www.aaa.org/links/rac-ssp2015/. For more observing events this summer, AAA's calendar updates frequently with location and other information ­ be sure to check back often at http://www.aaa.org/calendar.

Marcelo Cabrera president@aaa.org

FRI, July 17 @ 7 pm Columbia Summer Film & Stargazing at Pupin Hall, P
Guardians of the Galaxy (Observing 8:30 pm, C)

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

SAT, July 18 ­ 19 @ 8:00 pm ­ 2:30 am Next: Aug 15 ­ 16 AAA Observing at North-South Lake, Haines Falls, NY MPTC
Take a field trip with AAA to the Catskill Mountains in an exceptionally dark location for deep sky observing. For AAA members only. Reserve a spot by emailing treasurer@aaa.org.

Visit us online at www.aaa.org.
AAA Around Town
Educational Outreach at PS 116 On June 18, AAA visited the Science Lab Club at the PS 116 Mary Lindley Murray School for some daytime observing and astronomy appreciation. T h e a ft er sch ool club is one of several offered at PS 116. I gave a talk to the club's students, aged 7 to 10, about telescopes, observing, and Solar System objects. They sketched concepts on a whiteboard and shared their own stories of past astronomy events. The breadth of their knowledge and experience was impressive for such young people! We went outside and set up a four-inch refracting telescope in the playground, although clouds threatened above. But our persistence paid off, and students from the whole school were finally treated to a view of three sunspot groups and a waning crescent planet Venus. To learn more about AAA's Educational Outreach Program, email schooloutreach@aaa.org. Peter Tagatac

@ 8:30 pm ­ 11 pm Next: Aug 15 AAA Observing at Great Kills ­ Staten Island, PTC FRI, July 24 @ 6:45 pm ­ 11 pm Next: June 26 Astronomy Night at the Intrepid with AAA ­ Manhattan, PTC
Stargaze with AAA on the flight deck of the Intrepid! Learn about exoplanets with Astrophysicist Steve B. Howell and see Andrew Dawson's S pace Panoram a, a performance recreating the 1969 Apollo 11 Moon landing. Also enjoy live demos and trivia games with prizes! The event is free and open to the public, but registration is required at: http://www.intrepidmuseum.org/astronomynights.aspx.

@ 8 pm ­ 11 pm Next: June 26 AAA Observing at Carl Schurz Park ­ Manhattan, PTC SAT, July 25 @ 11:00 am ­ 1:00 pm Next: Aug 29 AAA Solar Observing at Poe Park ­ Bronx, PTC @ 8 pm ­ 10 pm Next: Aug 29 AAA Observing at Parkchester ­ Bronx, PTC TUES, July 28 @ 6:30 pm AMNH Astronomy Live at the Hayden Planetarium, P
"G r an d T ou r of t h e Un iv er se" wit h Br ia n Ab b ot . T r a vel fr om E a r t h to the most distant objects of the observable universe. (Enter 81 St)
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Eyepiece Staff
July Issue Editor-in-Chief: Amy M. Wagner
Copy Editor: Rich a r d Br ou n stein
Contributing Writers: R or i B ald ar i, T on y Fad d ou l, S t an ley Fer t ig, Stan Honda, Peter Tagatac, and Amy Wagner Eyepiece Logo and Graphic Design: R or i B ald ar i Administrative Support: J oe Delf au sse
Printing by McVicker & Higginbotham

@ 6:00 pm ­ 8:30 pm Next: Aug 25 AAA Solar Observing at the Highline ­ Manhattan, PTC
C: Cancelled if cloudy; M: Members only; P: Public event; T: Bring telescopes, binoculars.

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

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