NANOSAIL-D LOST: Sadly, NASA's NanoSail-D solar sail never reached Earth orbit. A SpaceX Falcon 1 rocket launched last night with the sail on board, but minutes after liftoff a stage-separation failure occurred; the mission was lost. Condolences to the mission team, and better luck next time! PERSEID METEORS: The August arc of Earth's orbit is littered with debris from comets, especially Comet Swift-Tuttle, the source of the annual Perseid meteor shower. Already, a few Perseids per hour are streaking across the night sky in advance of the shower's peak on August 11th-12th. August is Perseid-month. But not every meteor is a Perseid. Consider the following: "I've been out every clear night looking for meteors," says photographer Krzysztof Polakowski of Gniewowo, Poland. "On August 1st, I recorded this fireball of magnitude -7 (more than fifteen times brighter than Venus). Fantastic! Unfortunately, it was not a Perseid." The fireball did not fly out of the constellation Perseus as a Perseid would do. Instead, it was probably a sporadic, i.e., a random piece of comet or asteroid littering Earth's orbit, not part of any organized debris stream. Every hour of every night, a few sporadic meteors can be seen from any location on Earth. There are also several minor showers active in early August, especially the delta Aquariids, which produce 2 to 5 meteors per hour from an unknown comet. Adding these to the Perseids and sporadics makes the night sky pretty lively, and the Perseid peak is still more than a week away. Says Polakowski, "maybe in a few days I'll catch some Perseids." He probably will. MAGNIFICENT CORONA: The sun's wispy, dancing, mysteriously-hot outer atmosphere is one of the prettiest sights in the heavens. The trick is seeing it. Under normal circumstances, blinding sunlight hides the corona from sensitive human eyes. Last Friday, however, was not normal: Hartwig Luethen took the picture on August 1st when the Moon passed directly in front of the sun, briefly revealing the corona for all to see. To photograph the eclipse, Luethen stationed himself in Kochenovo, west of Novosibirsk, Russia, deep inside the path of totality. "I used a Canon 350D to make 24 exposures varying in length from 1/500 to 2 seconds." The resulting composite shows the ghostly corona, a magnetic prominence surging over the lunar limb, and the Earthlit surface of the Moon itself. Browse the gallery for more corona shots: UPDATED: Solar Eclipse Photo Gallery [interactive eclipse map] |