January 25, 2020

April 2009 News & Notes.

The Successful Launch of Kepler: The Kepler space telescope launched successfully last month on March 6th, during a spectacular night launch. Sporting one of the biggest CCD imagers ever to leave Earth, Kepler is bound for an Earth-trailing, heliospheric orbit. Kepler will spend several months staring at a patch of sky in the direction of Cygnus looking for one of the holy grails in astronomy; Earth-sized, terrestrial planets. Stay tuned! This could be one of the potential discoveries of the year!

Newfound Saturn Moon: A new moon has been added to the Saturnian menagerie; provisionally named S/2008 S1, discovery of this tiny moonlet of about half a kilometer in size was recently announced by Carolyn Porco of the Cassini spacecraft imaging team. It lurks within the wispy G ring, the outer-most ring in the Saturnian system and the last one to give up a source “Sheppard Moon…” It can be seen as a tiny glow in the arc in successive pictures above. Doubtless, a name will be forthcoming from the International Astronomical Union in the coming months. To date, 61 Saturnian moons are known, most of which are simply Titan plus debris. Having exhausted the Greek complement of Cronus’ (i.e. Saturn’s) “cronies”, names have come from the Norse and Inuit pantheons as of late. Cassini will take a closer look at the new moonlet in 2010 as part of its’ ongoing Saturn Equinox plane crossing mission.

The Hunt for Venusian water: Our nearest planetary neighbor still holds a major mystery; where did all its water go? Although Venus is the closest to us in apparent size, it is also bone dry. Very un-Earthlike! Now, the European Space Agencies’ Venus Express probe is shedding some light on the mystery. For the first time, scientists have evidence of escaping hydrogen from the Venusian daytime side. Unlike Earth, Venus does not have a protective magnetic field; instead, solar particles make their way unimpeded to the cloud tops. Much of Venus’ hydrogen and oxygen has been stripped away via this process; how much initially existed, or how it might be replenished, isn’t entirely clear, and may say a great deal about were water on Earth came from. Venus Express is in a unique orbit to carry out this examination; it loops in a highly elliptical path over the poles of the planet.

Betelgeuse Shockwave: We may never look at the constellation Orion the same way again… recently, scientists revealed data compiled from the little known Japanese observatory Akari, which conducted operations from 2006-2007. Akari was an infrared satellite, and it produced an IR all-sky map with a higher resolution than IRAS back in the 1980s. One of its main findings was that the red giant star Betelgeuse produces an enormous bow shock wave as it plows through space. About 3 light years in diameter, this shell would appear about as large as a Full Moon, if we were equipped with infrared vision, and these waves made it to the Earth’s surface without being absorbed by our atmosphere!

Pluto Occultation: New research reveals Pluto’s atmosphere like never before. Using the European Space Agencies’ (ESO) Very Large Telescope (VLT) array, scientists have identified a dynamic atmosphere, complete with inversion layers. This unprecedented look came during a stellar occultation, when the light from a background star was filtered through the tenuous atmosphere. Coupled to the VLT and key to observations was CRIRES, or the Cryogenic Infrared Echelle Spectrograph. It revealed an atmosphere of primarily nitrogen and less than 1% methane, which serves as a greenhouse layer keeping the atmosphere warmer than the surface. Of course, “warmth” in Pluto’s’ environs is relative; the difference of 50 degrees Celsius still means that the upper atmosphere is a balmy -170C! It is known that Pluto’s atmosphere tends to freeze to its surface as it begins its outward journey through its highly eccentric orbit; its anyone’s guess what New Horizons will find as it cruises by in 2015. Stay tuned!

Hidden Supernova : Astronomers have identified one of the nearest supernovae in the past quarter century using an unprecedented collaboration of data; SN 1996cr has been posthumously identified in the Circinus Galaxy, about 13 million light years distant. Astronomers first identified the bright X-ray source using the Chandra space telescope, then combed through archives from over 18 space and ground based observatories for additional data. Partially obscured by galactic dust, the object closely resembles its more familiar twin, SN 1987A that detonated about 160,000 light years distant in the Large Magellanic Cloud. Not only does this give us a chance to study a supernova up close, but also represents what could be a coming wave of future online collaborations, something which amateurs may take part. Both supernovae were of the massive Type II variety.

Target: Moon!: Earth’s humble Moon is in NASA’s cross-hairs again this year; and unlike the early unmanned probes, we’re deliberately crashing into our nearest neighbor these days! Part of the Lunar Reconnaissance Orbiter mission this year, LCROSS, the Lunar Crater Observation and Sensing Satellite, is part of an ongoing quest to find water at the Moon’s shady poles. No less than 4 observatories, including Apache point and the Large Binocular Telescope Mt. Graham in Arizona, will be watching, although the event may well be visible in modest sized backyard instruments. LCROSS and the LRO are slated for a May 21st launch from the Cape; watch this space for further updates!

(Magnetic Field video)

A Hole in Earth’s Magnetic Field? NASA’s THEMIS spacecraft continues to make some amazing discoveries…in addition to the reported “solar conduits”,  scientists have recently recorded large gaping holes opening up on the Sunward side of the Earth’s magnetosphere! Tendrils of charged solar wind particles have been observed cracking open the magnetic sheath that covers the Earth. The flow rate can be in the order of 1027 particles per second, and the gaping hole can be over 4 times the diameter of the Earth! This may set us up for a wild ride through Solar Cycle 24; for reasons not entirely understood, CME’s on even numbered cycles tend to smack the Earth with a northward polarity, identical to the magnetospheres’ equatorial polarity.

Launches for the Month: Firm dates and times are set for W2A telecommunications satellite aboard a Proton rocket out of the Baikonur Cosmodrome on April 3rd, a WGS 2 Atlas 5 on April 3rd and the GOES-O Launch April 28th out of Cape Canaveral Air Force Station… an interesting “To Be determined” launch is the burgeoning Indian Space programs’ Polar Satellite Lauch Vehicle out of Satish Dhawan Space Center in Sriharikota, India sometime in Early April.  Follow all launch updates at this link.

AstroBlooper of the Month: OK, let it be known that I like NBC’s Heroes Season 2, and I can overlook the use of a Solar Eclipse to explain bizarre super-powers in the cause of comic book-dom; in scifi, like cosmology (see below) you’re allowed one physics-bending gremlin, just not a flock of them! What bothered me is the repeated referral to the eclipse as a “total-annular…” you are either one or the other! I know, you’re saying that hybrid eclipses do exist; this could have been, in fact, an excellent chance to explain this. But what they repeatedly depicted was a total!

This Month in Astro-History: On April 4th, 1968, Apollo VI, the last unmanned Apollo mission, lifted off in what was to be a certification flight of the Saturn V system. The test was less than successful; about 120 seconds into the flight the rocket began to “pogo”, or oscillate and failed to achieve the desired orbit. Now a largely forgotten part of the Apollo saga, the launch was also a buried news item due to the assassination of Martin Luther King on the same day. The mission was also noteable for providing some unforgettable footage; everyone knows the famous shot of the inter-stage rings falling away, but few know that most of this footage comes from the unmanned Apollo VI mission!

Quote of the Month: “A theorist is allowed to introduce one tooth fairy into his theory-but only one.”

-Cosmologist Bohdan Paczynski

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