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alactic Observer GJohn J. McCarthy Observatory Volume 8, No. 9 September 2015 Stalking the Hunter A view of the Orion Nebula (M42) viewed through the dome at McCarthy Observatory and enhanced by our JJMO imaging team. For more information, see inside, page 13. 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 Allison Jim Johnstone Steve Barone Carly KleinStern Colin Campbell Bob Lambert Dennis Cartolano Roger Moore Route Mike Chiarella Parker Moreland, PhD Jeff Chodak Allan Ostergren Bill Cloutier Marc Polansky Cecilia Detrich Joe Privitera Dirk Feather Monty Robson Randy Fender Don Ross Randy Finden Gene Schilling John Gebauer Katie Shusdock Elaine Green Jon Wallace Tina Hartzell Paul Woodell Tom Heydenburg Amy Ziffer In This Issue OUT THE WINDOW ON YOUR LEFT .................................... 4 REFERENCES ON DISTANCES ............................................ 13 HYGINUS AND ARIADAEUS RILLES ..................................... 5 INTERNATIONAL SPACE STATION/IRIDIUM SATELLITES .......... 13 INTERNATIONAL OBSERVE THE MOON NIGHT ...................... 6 SOLAR ACTIVITY ........................................................... 13 VIEW FROM AFAR ........................................................... 6 COVER PHOTO CREDIT .................................................. 13 LUNAR ECLIPSE ............................................................. 7 COVER PHOTO .............................................................. 13 NEW WORLDS ............................................................... 8 SECOND SATURDAY STARS POSTER ................................... 14 MAVEN UPDATE ............................................................. 9 SEPTEMBER GRAPHIC CALENDAR .................................... 15 TETHYS ......................................................................... 9 RIDING THE COMET ....................................................... 10 THREE YEARS ON MARS ................................................. 10 AUTUMNAL EQUINOX ..................................................... 11 AURORA AND THE EQUINOXES .......................................... 11 SUNRISE AND SUNSET ...................................................... 11 SUMMER NIGHTS ........................................................... 11 PRESENT AND FUTURE POLE STARS .................................. 11 ASTRONOMICAL AND HISTORICAL EVENTS ......................... 11 2 • Sep 2015 http://www.mccarthyobservatory.org September Astronomy Calendar and Space Exploration Almanac http://www.mccarthyobservatory.org Sep 2015 • 3 “Out the Window Serenitatis (Sea of Serenity), the and appears to be volcanic in origin. on Your Left” Haemus Mountains on its south- The rille abruptly changes directions ern rim, the nearby Hyginus and at the Hyginus caldera. T’S BEEN OVER 40 years Ariadeus Rilles, the Apollo 16 The waxing crescent on the 19th since we left the last footprint landing site in the Descartes High- also provides an opportunity to ob- Ion the dusty lunar surface. lands, and the Altair Scarp. serve the elusive Valentine Dome. Sadly, as a nation founded on ex- The Hyginus and Ariadaeus The volcanic dome can be found on ploration and the conquest of new Rilles can be found near the Moon’s the western shore of Mare Serenitatis frontiers, we appear to have lost equator, just to the west of Mare and is approximately 24 miles (39 our will to lead as a space-faring Tranquilitatis (Sea of Tranquility). km) across but less than 1,200 feet nation. But, what if the average Rima Ariadaeus starts near the west- (350 meters) high. It’s only visible citizen had the means to visit our ern shore of Mare Tranquillitatis and when near the terminator. only natural satellite; what would runs towards Mare Vaporum to the The Altai Scarp is a prominent they see out the window of their west. The linear fault or graben is feature in the southern highlands spacecraft as they entered orbit 186.4 miles (300 km) in length. Av- when the Sun is low in the lunar around the Moon? This column eraging 3.1 miles (5 km) in width, sky. The arcing cliff rises to a may provide some thoughts to pon- Rima Ariadaeus slices through other, height of 2 to 2½ miles (3.5 to 4 der when planning your visit (if presumably older geologic features. km) and is a remnant of the mul- only in your imagination). Rima Hyginus emerges from the tiple mountain rings that typically shadows in the west and is punctu- encircle large impact basins. This ated by a series of small rimless pits particular scarp is part of the outer and the Hyginus caldera. Its length ring of the Nectaris impact basin, is approximately 136 miles (219 km) one of the oldest on the Moon. The International Observe the Moon Night is an annual event sponsored by NASA’s Lunar Re- connaissance Orbiter, NASA’s So- lar System Exploration Research Virtual Institute, and the Lunar and Planetary Institute to encourage lunar observation and its connec- tion to solar system exploration. This year (2015), the event is scheduled for September 19th. Ad- ditional information on scheduled events can be found at http:// observethemoonnight.org/. A six day old Moon will be vis- ible on the 19th to observers with clear skies. The terminator (divid- Formerly known as Linné Alpha the ellipticall feature bisected by a ing the sunlit and shadowed por- rille at left of center has been popularly dubbed Valentine Dome, tions of the near-side) will traverse perhaps because it suggested a heart pierced by an arrow - or the western reaches of Mare perhaps just a big pizza pie..[Source: NASA/GSFC/Arizona State University.] 4 • Sep 2015 http://www.mccarthyobservatory.org Hyginus and Ariadaeus Rilles http://www.mccarthyobservatory.org Sep 2015 • 5 International Observe the Moon Night The Moon will rise shortly after noon on September 19th and set at 10:39 pm. Approximately 36% of the near-side surface will be illu- minated, similar to the image cap- tured below. Photo notations cor- respond to the 1) Valentine Dome and Mare Serenitatis; 2) Hyginus and Ariadeus Rilles; 3) Mare Tranquillitatis; 4) Descartes Highlands and the Apollo 16 landing sit, and 5) the Altai Scarp and Mare Nectaris. View from Afar The Deep Space Climate Observatory (DSCOVR) satellite is a collaborative mission between NASA, NOAA and the U.S. Air Force. The satellite is positioned 1 Photo: Bill Cloutier million miles from Earth, between the Earth and the Sun. Its primary mission is to provide real time data on the solar wind for use in space weather forecasts and alerts. The satellite is also equipped with a four megapixel CCD camera and telescope that is used to image the Earth as it rotates, pro- viding data on ozone, vegetation, clouds and aerosols in the atmo- sphere. On July 16th, the camera also captured the Moon as it passed between the satellite and the Earth, providing a view seldom seen of the Moon's fully illuminated far side. Unlike the side facing the Earth, there are relatively few maria on the Moon's far side. The most prominent patch of lava seen in the image is Mare Moscoviense (Sea of Moscow) in the upper left of the lunar orb. Credits: NASA/NOAA 6 • Sep 2015 http://www.mccarthyobservatory.org Lunar Eclipse On the evening of September 27th, the full Moon will slip into the Earth's shadow. Once in the shadow, the Earth will block all direct sun- light from illuminating the lunar sur- face. This arrangement, with the Earth in line between the Sun and the Moon, produces a lunar eclipse. The image at the right was taken at the McCarthy Observatory on October 27, 2004. It shows the Moon nearing the completion of its travel through the darkest part of the Earth's shadow (or umbra). The crimson glow is from sunlight scattered by the Earth's atmosphere that has fil- tered out most of the blue colored light. The northern limb of the Moon Photo: Bill Cloutier is brighter as it is closest to the edge of the umbra. On the 27th, the Moon ing 72 minutes. The entire eclipse "September’s full moon will be will travel through the southern half will be visible to viewers on the east the closest to the Earth in 2015 of umbra. The eclipse will be vis- coast. The Moon will be rising with (221,755 miles or 356,880 km) and ible (weather permitting) for observ- the eclipse in progress for viewers appear the largest. The next total ers in North America, with totality on the west coast, with moonrise lunar eclipse visible in the north- starting at 10:11 pm EDT and last- just before the onset of totality. east U.S. will be in January 2019." Total eclipse begins (Moon completely within the umbra) 10:11:10 pm EDT Total eclipse ends (Moon begins to exit umbra) 11:23:05 am EDT http://www.mccarthyobservatory.org Sep 2015 • 7 New Worlds NASA/JHUAPL/SWRI On July 14th, after nine and one-half years and more than 3 million miles (5 million km), the wait was finally over when the New Horizons spacecraft pro- vided earthlings their first up close view of Pluto, its compan- ion moon and diminutive satel- lites. While it will take almost 16 months to transmit all the data collected by New Horizons
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