The Approach Begins Ceres Pluto
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— February 2015— The Newsletter Of The Sheep Hill Astronomical Association The Approach Begins Ceres Pluto Two Separate Spacecrafts Appraoch Two Different Dwarf Planets!! And More!
2 NOVA — Month 2015 Sheep Hill Astronomical Association ON THE COVER PUT THUMBNAIL HERE NOVA is the official newsletter of the Sheep Hill Astronomical Association. It is Dawn begins ap- published once each month and a sub- scription is included with your member- proach to Ceres ship to SHAA. Dawn has entered its approach phase toward Ceres and will arrive Club Officers on March 6, 2015 President Pat Boyle portant ways. Ceres may have NASA's Dawn spacecraft has en- formed later than Vesta, and with a Admin Vice Pres. Robert Moravsik tered an approach phase in which it cooler interior. Current evidence sug- Tech Vice Pres. Nick Sperling will continue to close in on Ceres, a gests that Vesta only retained a small Treasurer Phil Schwartz Texas-sized dwarf planet never be- amount of water because it formed fore visited by a spacecraft. Dawn earlier, when radioactive material Secretary Daniel Cleary launched in 2007 and is scheduled was more abundant, which would UACNJ Delegate Warren Westura to enter Ceres orbit in March 2015. have produced more heat. Ceres, in Dawn is currently 400,000 miles contrast, has a thick ice mantle and may even have an ocean beneath its Committee Chairs (640,000 kilometers) from Ceres, icy crust. approaching it at around 450 miles Fundraising: Dino Cappello per hour (725 kilometers per hour). Ceres, with an average diameter of Observatory: Patrick Boyle The spacecraft's arrival at Ceres will 590 miles (950 kilometers), is also the mark the first time that a spacecraft largest body in the asteroid belt, the Outreach: Ted Winsch has ever orbited two solar system strip of solar system real estate be- Publicity: Nick Sperling tween Mars and Jupiter. By compari- targets. Dawn previously explored Program: Phil Schwartz the protoplanet Vesta for 14 son, Vesta has an average diameter months, from 2011 to 2012, captur- of 326 miles (525 kilometers), and is ing detailed images and data about the second most massive body in the Contribute that body. belt. "Ceres is almost a complete mystery The spacecraft uses ion propulsion to Producing our newsletter is a tre- to us," said Christopher Russell, traverse space far more efficiently mendous undertaking each month. principal investigator for the Dawn than if it used chemical propulsion. In We are always looking for help mission, based at the University of an ion propulsion engine, an electri- writing articles, compiling data, or California, Los Angeles. "Ceres, un- cal charge is applied to xenon gas, even just suggesting ideas. If you like Vesta, has no meteorites linked and charged metal grids accelerate have anything to contribute, or to it to help reveal its secrets. All we the xenon particles out of the thrust- would like to help out, contact Nick can predict with confidence is that er. Dawn has now completed five Sperling. we will be surprised." years of accumulated thrust time, far This newsletter is copyright © 2015 Sheep more than any other spacecraft. The two planetary bodies are Hill Astronomical Association. All Rights "Orbiting both Vesta and Ceres thought to be different in a few im- Reserved.
3 NOVA — Month 2015 would be truly impossible with con- ventional propulsion. Thanks to ion propulsion, we're about to make his- tory as the first spaceship ever to orbit two unexplored alien worlds," said Marc Rayman, Dawn's chief engi- neer and mission director, based at NASA's Jet Propulsion Laboratory in Pasadena, California. The next couple of months promise continually improving views of Ceres, prior to Dawn's arrival. By the end of January, the spacecraft's images and other data will be the best ever taken of the dwarf planet. The Dawn mission to Vesta and Ceres is managed by JPL, a division of the Timeline of the approach and departure phases — surrounding close approach on California Institute of Technology in July 14, 2015 — of the New Horizons Pluto encounter. Pasadena, for NASA's Science Mission Directorate, Washington. UCLA is responsible for overall Dawn mission Science Division at the agency’s 135 million miles (220 million kilome- science. Headquarters in Washington. “The ters) to Pluto. More information about Dawn: New Horizons team worked very “We’ve completed the longest jour- hard to prepare for this first phase, http://dawn.jpl.nasa.gov ney any spacecraft has flown from and they did it flawlessly.” Earth to reach its primary target, and The fastest spacecraft when it was we are ready to begin exploring,” Meanwhile, beyond Neptune: launched, New Horizons lifted off in said Alan Stern, New Horizons princi- January 2006. It awoke from its final pal investigator from Southwest Re- NASA's New Horizons spacecraft re- hibernation period last month after search Institute in Boulder, Colorado. cently began its long-awaited, histor- a voyage of more than 3 billion ic encounter with Pluto. The space- LORRI will take hundreds of pictures miles, and will soon pass close to craft is entering the first of several of Pluto over the next few months to Pluto, inside the orbits of its five approach phases that culminate July refine current estimates of the dis- known moons. In preparation 14 with the first close-up flyby of the tance between the spacecraft and dwarf planet, 4.67 billion miles (7.5 The images captured by New Hori- the dwarf planet. Though the Pluto billion kilometers) from Earth. zons’ telescopic Long-Range Recon- system will resemble little more than naissance Imager (LORRI) will give bright dots in the camera’s view until “NASA first mission to distant Pluto mission scientists a continually im- May, mission navigators will use the will also be humankind’s first close proving look at the dynamics of data to design course-correction ma- up view of this cold, unexplored Pluto’s moons. The images also will neuvers to aim the spacecraft toward world in our solar system,” said Jim play a critical role in navigating the its target point this summer. The first Green, director of NASA’s Planetary spacecraft as it covers the remaining such maneuver could occur as early
4 NOVA — Month 2015 as March. telescopes on Earth. Eventually, the spacecraft will obtain images good “We need to refine our knowledge of enough to map Pluto and its moons where Pluto will be when New Hori- more accurately than achieved by previ- zons flies past it,” said Mark ous planetary reconnaissance missions. Holdridge, New Horizons encounter mission manager at Johns Hopkins APL manages the New Horizons mission University’s Applied Physics Labora- for NASA’s Science Mission Directorate tory (APL) in Laurel, Maryland. “The in Washington. Alan Stern, of the flyby timing also has to be exact, be- Southwest Research Institute (SwRI), cause the computer commands that headquartered in San Antonio, is the will orient the spacecraft and point the science instruments are based on principal investigator and leads the mis- precisely knowing the time we pass sion. SwRI leads the science team, pay- Pluto – which these images will help load operations, and encounter science us determine.” planning. New Horizons is part of the New Frontiers Program managed by The “optical navigation” campaign NASA's Marshall Space Flight Center in that begins this month marks the first Huntsville, Alabama. APL designed, built time pictures from New Horizons will be used to help pinpoint Pluto’s loca- and operates the spacecraft. tion. For more information about the New Throughout the first approach phase, Horizons mission, visit: which runs until spring, New Horizons www.nasa.gov/newhorizons will conduct a significant amount of additional science. Spacecraft instru- and ments will gather continuous data on http://pluto.jhuapl.edu the interplanetary environment where the planetary system orbits, including measurements of the high- energy particles streaming from the sun and dust-particle concentrations in the inner reaches of the Kuiper Belt. In addition to Pluto, this area, the unexplored outer region of the solar system, potentially includes thousands of similar icy, rocky small planets. More intensive studies of Pluto begin in the spring, when the cameras and spectrometers aboard New Horizons will be able to provide image resolu- tions higher than the most powerful
5 NOVA — Month 2015 IN THE SKY THIS MONTH Lunar Phases Solar System MERCURY—Well placed in the morning sky from 6th to the 28th Feb 03 Feb 11 Feb 18 Feb 25 VENUS—Night of 20/21 Conjunction with Mars and Moon. Night of 21/22 Conjunc- The Sun and Astronomical Twilight Twilight Sun Sun Twilight tion with Mars Begin Rise Set End MARS—See Venus Feb 01 5:34 07:09 17:13 18:48 JUPITER—Opposition on the 6th Feb 15 05:21 06:53 17:31 19:03 Feb 28 05:03 06:34 17:46 19:17 URANUS—Occultation by moon on the 21st Telescopic Tour for February Object h m ° ‘ ψ Draconis, double star 17 41.9 +72 10 N. American Nebula 20 58.8 +44 20 Highlights M31 Andromeda Galaxy 0 42.7 +41 16 Feb 01 All month comet C/2014 Q2 M33, Trianglum Galaxy 1 33.9 +30 39 Lovejoy visible in binoculars γ Andromadae, dbl star 2 03.9 +42 20 but receding Perseus double cluster 2 21.5 +57 08 Feb 01 Capricornid/Sagittarid mete- ι Cassiopeiae, triple star 2 29.0 +67 24 ors (radio shower) Pleiades M45 3 47.5 +24 06 Feb 02 Candlemas (a.k.a) Goundhog R Leporis, crimson star 4 59.6 -14 47 day, one of four days halfway M1 Crab Nebula 5 34.5 +22 01 between Solstice and equi- M42 Orion Nebula 5 35.4 -5 22 nox. σ Orionis Multiple Star 5 38.7 -2 35 Feb 06 Jupiter Reaches magnitude - M35 Cluster 6 08.9 +24 21 2.6 during opposition on the 6th Rosette Nebula 6 32.4 +4 52 Castor, double star 7 34.6 +31 54 Feb 08 Alpha Centaurid Meteors Praesepe Cluster 4 40.4 +19 41 Feb 19 Moon at perigee, large tides M81 Bode’s Galaxy 9 55.6 +69 04 for next three days γ Leonis, double star 10 19.9 +19 51 Feb 20 Moon, Mars and Venus in Mizar, double star 13 23.9 +54 55 conjunction Feb 21 Mars and Venus even closer, 0.5 degrees apart. Uranus Occulted by the Moon.
6 NOVA — Month 2015 SPACE NEWS Minor mergers have mas- isolated clump of matter, but by binary black hierarchical mergers of smaller gal- holes like this. sive consequences for axies over tremendous timescales. Examples like NGC 3393 and IC 4970 If galaxies with large amounts of are not only confirming our picture of black holes stars all have black holes at their galaxy growth and formation, but are centers, then we should be able to teaching us that supermassive relics By: Dr Ethan Siegel see some fraction of Milky Way- from ancient, minor mergers might Courtesy of NASA’s Space Place sized galaxies with not just one, but persist as standalone entities for multiple supermassive black holes longer than we ever thought! at their center! When you think of our sun, the near- Check out some cool images and est star to our world, you think of an It was only in the early 2000s that artist reconstructions of black holes isolated entity, with more than four NASA's Chandra X-ray Observatory from Chandra: http:// light years separating it from its next was able to find the first binary su- chandra.harvard.edu/photo/ nearest neighbor. But it wasn't al- permassive black hole in a galaxy, category/blackholes.html ways so: billions of years ago, when and that was in an ultra-luminous Kids can learn all about Black Holes our sun was first created, it very like- galaxy with a double core. Many from this cool animation at NASA’s ly formed in concert with thousands other examples were discovered Space Place: http:// of other stars, when a giant molecu- since, but for a decade they were all spaceplace.nasa.gov/black-holes. lar cloud containing perhaps a million in ultra-massive, active galaxies. times the mass of our solar system That all changed in 2011, with the collapsed. While the vast majority of discovery of two active, massive stars that the universe forms—some black holes at the center of the reg- ninety-five percent—are the mass of ular spiral galaxy NGC 3393, a gal- our sun or smaller, a rare but signifi- axy that must have undergone only cant fraction are ultra-massive, con- minor mergers no less than a billion taining tens or even hundreds of years ago, where the black hole pair times the mass our star contains. is separated by only 490 light years! When these stars run out of fuel in It's only in the cores of active, X-ray their cores, they explode in a fantas- emitting galaxies that we can detect tic Type II supernova, where the star's core collapses. In the most massive cases, this forms a black hole. Over time, many generations of stars—and hence, many black holes—form, with the majority even- tually migrating towards the centers of their host galaxies and merging together. Our own galaxy, the Milky Way, houses a supermassive black hole that weighs in at about four mil- lion solar masses, while our big sister, Andromeda, has one nearly twenty times as massive. But even relatively Images credit: NGC 3393 in the optical (L) by M. Malkan (UCLA), HST, NASA (L); NGC isolated galaxies didn't simply form 3393 in the X-ray and optical (R), composite by NASA / CXC / SAO / G. Fabbiano et al. from the monolithic collapse of an (X-ray) and NASA/STScI (optical).
7 NOVA — Month 2015 CLUB NEWS Next Meeting Qualification The next meeting of SHAA will be Congratulations to Patrice Debe, held on Feb 8th, 2015 at the Jennifer Graeff, and Gary Scimeca Boonton Senior Center. who are now qualified observers. Astronomical Presentation: 7:30PM Anyone interested in becoming a — Open to the Public. The program qualified observer should contact for the evening will be “An Observer's Nick Sperling or Pat Boyle. A Guide for the Sheep Hill Observatory “ qualified observer is permitted to by Ted Winsch. operate the Sheep Hill Observatory Business Meeting: 8:30PM—Open for public and private astronomical to the Public. viewing. A minimum of five events combined (Public Nights, Club Nights) and three business meetings per year are necessary to retain Annual Dues your qualified observer status. Yearly club membership dues for Training will be scheduled on 2015 are now due. You may send in request and includes one daytime your payment to SHAA, PO Box 111, and one nighttime session. Boonton NJ or give your payment directly to our club treasurer at one of the business meetings. Family membership remains at $40.00 per year. Sheep Hill Astronomical Assn PO Box 111 Boonton, NJ 07005 www.sheephillastro.org
8 NOVA — Month 2015 SHAA CALENDAR Image Credit: NASA February 2015 Some prefer windows, and these are the best available on board the International Space Station. Taken on January 4, this snap- shot from inside the station's large, seven-window Cupola module also shows off a workstation for controlling Canadarm2. Used to grapple visiting cargo vehicles and assist astronauts during spacewalks, the robotic arm is just outside the window at the right. Sun Mon Tue Wed Thu Fri Sat 1 2 3 4 5 6 7 8 9 10 11 12 13 14 SHAA Meeting 15 16 17 18 19 20 21 Public Night Club Night 22 23 24 25 26 27 28
9 NOVA — Month 2015 MEMBERSHIP The Membership List Will Now Be Maintained as a Separate Document Membership in the Sheep Hill Astronomical Association is open to any individual with an interest in astronomy. You need not own a telescope or other equipment to become a member of the Sheep Hill Astronomical Association. Annual dues requirements are: Adult (All family members included) $40.00 Student Membership $21.25 Senior Citizen $32.50 (under age 14, parent must join) Business meetings are held on the first Sunday of each month at 7:30 P.M. at the Boonton Senior Center. The annual dues are payable at the regular January meeting of the Association. For individuals joining the Association after July 1st, the dues will be one half of the regular annual dues. Shortly after payment of dues a new member is entitled to receive a membership card and NOVA, the SHAA newsletter. The new member is entitled and encouraged to begin qualification on the use of the 18” telescope housed in Sheep Hill Observatory. All members must be at least 18 years of age to be a “qualified observer”. All “qualified observers” must adhere to the rules of operation of the Sheep Hill Observatory. Membership Application Name: Address: Membership Type (select one) City: State: Zip Code: Adult / Family ($40.00) Phone: Senior Citizen ($32.50) E-mail: Student (Age 14+) ($21.25) If you own a telescope, please describe the type and aperture: Complete this application and bring to a meeting with your dues, or mail to: Sheep Hill Astronomical Association P.O. Box 111 Boonton, NJ 07005
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