Article By: Frank Jordans
Hundreds of millions of miles from Earth, a European spacecraft released a lander toward the icy, dusty surface of a speeding comet Wednesday, setting off a 7-hour countdown to an audacious attempt to answer some big questions about the origin of the universe. Due to the vast distances involved & the time delays in receiving data, confirmation of a landing should reach Earth about 1603 GMT (11:03 a.m. EST).
Scientists have likened the trillion or so comets in our solar system to time capsules that are virtually unchanged since the earliest moments of the universe. “By studying 1 in enormous detail, we can hope to unlock the puzzle of all of the others,” said Mark McCaughrean, a senior scientific adviser to the mission.
Philae was supposed to drift down to the comet & latch on using harpoons & ice screws. ESA announced hours before the release that a 3rd component — an active descent system that uses thrust to prevent the lander from bouncing off the surface of the low-gravity comet — could not be activated. It wasn’t clear how big of a setback that was. During the descent, scientists are powerless to do anything but watch bc the vast distance to Earth — 500 million kilometers (311 million miles) — makes it impossible to send instructions in real time. It takes more than 28 mins for a command to reach Rosetta.
Rosetta, which was launched in 2004, had to slingshot 3 times around Earth & once around Mars before it could work up enough speed to chase down the comet, which it reached in August. Rosetta & the comet have been traveling in tandem ever since. If the lander’s mission is successful, Rosetta & Philae plan to accompany the comet as it hurtles past the sun & becomes increasingly active in the rising temps. Using 21 different instruments, the twin spacecraft will collect data that scientists hope will help explain the origins & evolution of celestial bodies, & maybe even life on Earth.
Tantalizingly, the mission will also give researchers the opportunity to test the theory that comets brought organic matter & water to Earth billions of years ago, said Klim Churyumov, 1 of the 2 astronomers who discovered the comet in 1969. The European Space Agency says even if Philae’s landing doesn’t succeed, the 1.3 billion-euro ($1.6 billion) mission won’t be a failure bc Rosetta will be able to perform about 80% of the scientific mission on its own.
View full article at: http://news.yahoo.com/scientists-set-historic-comet-landing-attempt-072512433.html
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