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Jjmonl 1403.Pmd alactic Observer GJohn J. McCarthy Observatory Volume 7, No. 3 March 2014 Speed Demon In space there are no traffic cops. In this image taken by the Spitzer space telescope, a runaway star, HD 2905, 4,000 light years away in the constellation Cassiopeia, is barreling across our galaxy at 2.5 million miles per hour relative to its neighbors (1,100 km per second). This massive insult is causing the diffuse particles of interstellar dust and gas in its way to glow red – a phenomen called bow shock. Credit: NASA/JPL-Caltech The John J. McCarthy Observatory Galactic Observer New Milford High School Editorial Committee 388 Danbury Road Managing Editor New Milford, CT 06776 Bill Cloutier Phone/Voice: (860) 210-4117 Production & Design Phone/Fax: (860) 354-1595 www.mccarthyobservatory.org Allan Ostergren Website Development JJMO Staff Marc Polansky It is through their efforts that the McCarthy Observatory Technical Support has established itself as a significant educational and Bob Lambert recreational resource within the western Connecticut Dr. Parker Moreland community. Steve Barone Jim Johnstone Colin Campbell Carly KleinStern Dennis Cartolano Bob Lambert Mike Chiarella Roger Moore Route Jeff Chodak Parker Moreland, PhD Bill Cloutier Allan Ostergren Cecilia Detrich Marc Polansky Dirk Feather Joe Privitera Randy Fender Monty Robson Randy Finden Don Ross John Gebauer Gene Schilling Elaine Green Katie Shusdock Tina Hartzell Jon Wallace Tom Heydenburg Paul Woodell Amy Ziffer In This Issue "OUT THE WINDOW ON YOUR LEFT" ............................... 3 ZODIACAL LIGHT ........................................................... 15 MARE NECTARIS ............................................................ 4 MARCH NIGHTS ............................................................ 15 SUPERNOVA IN M82 ........................................................ 5 SUNRISE AND SUNSET ...................................................... 16 OCCULTATION OF REGULUS BY AN ASTEROID ....................... 6 JUPITER AND ITS MOONS ................................................. 16 COLD CASE SOLVED?...................................................... 7 TRANSIT OF JUPITER'S RED SPOT ..................................... 16 FIRST TO SPACEWALK ...................................................... 8 ASTRONOMICAL AND HISTORICAL EVENTS ......................... 16 WATER DETECTED ON CERES ........................................... 9 REFERENCES ON DISTANCES ............................................ 19 "REPORTS OF MY DEATH HAVE BEEN GREATLY EXAGGERATED"10 INTERNATIONAL SPACE STATION AND IRIDIUM SATELLITES .... 19 A BAD DAY ON MARS .................................................... 11 SOLAR ACTIVITY ........................................................... 19 ASTROPHOTOGRAPHY ..................................................... 12 PHOTO CREDITS ............................................................ 19 TWIST OF FATE ............................................................. 13 SECOND SATURDAY STARS ............................................... 20 COMET HISTORY ........................................................... 13 MARCH GRAPHIC CALENDAR .......................................... 21 MARCH HISTORY .......................................................... 14 THE POWER OF READING ............................................... 14 MORE MARCH HISTORY ................................................ 15 WINTER FAVORITE ........................................................ 15 2 • Mar 2014 http://www.mccarthyobservatory.org March Calendar and Space Exploration Almanac o d ( 1 w h v 3 t p i John Harrison's first "sea clock" (H1) is currently on display at the Royal Observatory in Greenwich. It was constructed between 1730 and 1735 as a means of finding longitude at sea. Photo Credit: National Maritime Museum http://www.mccarthyobservatory.org Mar 2014 • 3 “Out the Window on Your Left” of its terraced walls and central peaks are buried deep T’S BEEN MORE THAN 40 years since we left beneath the lava. A low lying lava dome with a sum- the last footprint on the dusty lunar surface. Sadly, mit pit is visible just to the north of the crater wall. Ias a nation founded on exploration and the con- Southeast of Theophilus, and north of Beaumont, is a quest of new frontiers, we appear to have lost our will small crater with a dark halo. The dark material was origi- to lead as a space-faring nation. But, what if the aver- nally thought to be deposits of pyroclastics around a vol- age citizen had the means to visit our only natural sat- canic vent. However, further studies suggest that the ellite; what would they see out the window of their material around this particular crater (Beaumont-L) is spacecraft as they entered orbit around the Moon? This the darker mare basalt excavated by the impact that cre- ated the crater. The basalt had been covered by lighter ejecta from the impacts that had created the larger cra- ters, like Theophilus and Fracastorius. Mare Nectaris occupies one of the oldest impact basins on the nearside of the Moon and is believed to have formed 3.92 billion years ago. Three impact rings (portions designated by yellow arcs) have been iden- tified with the basin: the Inner Ring (250 miles (400 km) in diameter) contains the mare lavas, the next larger but less distinct Catharina Ring at 375 miles (600 km) in diameter and outer Altai Ring (not shown) at 525 miles (840 km) in diameter. A view of the central peak of Theophilus crater, formed by ejecta forced up by an impact Lunar mare or "seas" are actually expansive event about 1.1 low-lying plains formed by ancient lava flows billion years column may provide some thoughts to ponder when ago. Credit: planning your visit (if only in your imagination). NASA/GSFC/ The view this month is dominated by Mare Nectaris Arizona State (the Sea of Nectar) and two large craters along its shore University that suffered dramatically different fates. Only the rim of the 62 mile (100 km) diameter complex crater Theophilus is sunlit in the image on the following Theophilus page. Fourteen thousand feet below the rim and hid- crater with the den in darkness, is a smooth, flat floor and a massive, central peaks central peak complex. Impact melt pooled north of marked in red. the crater wall provides visual evidence of the power These peaks of an ancient impact that could liquefy solid rock. consist of crustal Basaltic fragments from Mare Nectaris may have rock, forced up been transported more than 200 miles (350 km) by from deep below the impact, based upon the samples collected by both the surface the Apollo 11 and 16 astronauts. during the While almost identical in size to Theophilus, the impact event fractured-floor crater Fracastorius is a shell of its Credit: NASA/ former self. Located at the southern end of Mare GSFC/Arizona Nectaris, the crater has been flooded by mare lavas State University through breaches in its northern wall. Any remnants 4 • Mar 2014 http://www.mccarthyobservatory.org Mare Nectaris and Crater Fracastorius SchillerImpact Melt Crater Ponds and the Schiller-Zucchius Basin Theophilus Daguerre Dark Halo Crater Mare Serenitatis Mare Nectaris Beaumont Rosse Volcanic Dome Fracastorius Orion Rules the Winter Sky Mare Imbrium http://www.mccarthyobservatory.org Mar 2014 • 5 Supernova in M82 Twelve million years ago in a galaxy far, far away, explosion is moving away from the core at velocities a small white dwarf star underwent a cataclysmic deto- up to 12,500 miles per second (20,000 km/s). nation. The light from this event started its journey Marc Polansky imaged the galaxy and its supernova through space before humans walked upright upon the (marked by yellow bars) on the night of January 24th from dry land and raised their eyes to the star filled sky. On the McCarthy Observatory. The composite image below January 21st, students at the University of London Ob- was created by combining a total of 10 minutes of expo- servatory selected the galaxy (M82) as an observing sure time through various colored filters. target during a demonstration of CCD camera tech- Type 1a supernovas are of particular interest to nology by astronomer Steve Fossey. The first images astronomers. Since the detonation is the result of a acquired that night showed a new, bright star super- critical mass, which is a constant, the luminosity from imposed on the galaxy. the explosion is nearly the same from star to star. This The supernova had gone undetected for almost a allows astronomers to use this type of supernova as a week and has been since classified as a Type 1a su- “standard candle” from which to measure vast dis- pernova. The detonation of a white dwarf is thought tances (by comparing the luminosity of the supernova to be caused by the runaway fusion of carbon and in a distant galaxy to what if would have been if it had oxygen within the core of the star. The chain reaction occurred nearby. The study of Type 1a supernovas has is triggered by mass drawn from a nearby companion also contributed to our understanding of the expan- star, until a critical mass is reached. Debris from the sion of the universe. Marc Polansky imaged the galaxy and its supernova (marked by yellow bars) on the night of January 24th from the McCarthy Observatory. The composite image (above) was created by combining a total of 10 minutes of exposure time through various colored filters. 6 • Mar 2014 http://www.mccarthyobservatory.org Occultation of Regulus by an Asteroid Observers in central New York State and western ers to
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