Wednesday, May 21, 2008

103 impact flashes recorded on the Moon - in just 2½ years

It was just a matter of doing it: monitoring the dark part of the Moon with sensitive video cameras from separate locations and looking for flashes seen by both cameras at the same time in the same place. Cosmic ray hits on the detector, satellite glints etc. could be excluded this way - and now this approach has netted 100+ events in just two and a half years. "A typical blast is about as powerful as a few hundred pounds of TNT," says Bill Cooke, head of NASA's Meteoroid Environment Office at the Marshall Space Flight Center (MSFC), "and can be photographed easily using a backyard telescope."

The program was started in late 2005 as an early preparation for a possible return to the Moon. Almost immediately, on 7 Nov. 2005, a 7 mag. flash was detected. Meteoroids hit the moon with tremendous kinetic energy, traveling 50,000 km/h or faster: At that speed, even a pebble can blast a meter-wide crater. The impact heats up rocks and soil on the lunar surface hot enough to glow like molten lava - hence the flash. During meteor showers the rate of lunar flashes can go as high as one per hour; impacts subside when the Moon exits the stream, but curiously the rate never goes to zero.

In other news comet Boattini - seen here from Namibia in Apr./May - is rather bright but poorly placed for Northerners. • A detailled study of the break-up of the parent body of the Geminids - seen here from Portugal in 2007 - concludes "that the stream is the product of catastrophic, rather than steady-state, breakup of the parent object." • Windspeeds in Jupiter's Little Red Spot are higher than in the original storms that merged.

• The 4th and 5th exoplanet discoveries of the XO project in which amateurs play a key role. • Two more CoRoT planets have been confirmed - and there are 40+ more candidates, according to AW&ST of 14 Jan. p. 49. • Another Galaxy Zoo paper, this time on the independence of morphology and colour. • A speculative new idea about shadow bands seen at solar eclipses - a phenomenon considered explained for decades, actually.

• A semi-astronomical expedition report from Namibia zum Mai-Neumond ins namibische Hochland. • A fine ISS viewing window is now open in the N hemisphere: Check out Heavens Above for your local times to see space station - imaged here in hi-res on May 14. • Finally there is now a video celebrating the heroic attack on the satellite, edited by LockMart ...

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