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Astronomy Picture of the Day -- Descent to a Comet
NASA ^ | November 13, 2014 | (see photo credit)

Posted on 11/13/2014 2:43:12 PM PST by SunkenCiv

Explanation: Yesterday, the first soft landing on a comet took place some 500 million kilometers from planet Earth as the Rosetta mission lander Philae settled on the nucleus of C67/P Churyumov-Gerasimenko. The landing site, dubbed Agilkia, is located near the center of this remarkable image snapped by Philae's ROLIS (ROsetta Lander Imaging System) camera. Taken from a distance of about 3 kilometers the image has a resolution of about 3 meters per pixel at the surface. After Philae's release from the orbiter, its seven-hour long descent was made without propulsion or guidance. Following its descent the lander is in place, though its anchoring harpoon system did not fire. For 2.5 days the lander is intended to conduct its main science mission returning extensive images and data. An extended surface mission may be possible if sunlight and dust conditions allow solar panels to recharge Philae's battery.

November 13, 2014

(Excerpt) Read more at 129.164.179.22 ...


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; astronomy; churyumovgerasimenko; comet; comet67p; philae; rosetta; science
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To: Zuben Elgenubi
I’m betting it’s made up primarily of rock and ice. lol

I'm betting that like every other comet we've visited or flown by, there will be NO ICE, just rock.

21 posted on 11/13/2014 7:15:14 PM PST by Swordmaker (This tag line is a Microsoft insult free zone... but if the insults to Mac users continue...)
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To: dr_lew
The harpoon was a sort of skyhook, wasn’t it? I don’t know why they didn’t have a thruster. It wouldn’t have required much - just some compressed gas, maybe. Tried and true.

The had a nitrogen thruster to push the lander against the comet so the landing pad "ice screws" could "drill in" to hold the lander down, after the "harpoon" dug its way into the "icy surface of the comet." That all failed. Oops. The thruster failed to operate. The lander did not stay on the surface so the leg screws could attach, instead the lander "bounced" one kilometer into space before coming down and "landing" without another bounce (how was that accomplished? Or was it really a "non-destructive crash landing?"), apparently, they say on its side, in the shade of a cliff where it will only get a portion of the sunlight it needs to keep the battery charged, a kilometer away from the carefully selected landing site, with no way to try again.

22 posted on 11/13/2014 7:24:20 PM PST by Swordmaker (This tag line is a Microsoft insult free zone... but if the insults to Mac users continue...)
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To: SunkenCiv

Whitey still on the Moon!


23 posted on 11/13/2014 7:28:08 PM PST by Rome2000 (SMASH THE CPUSA)
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To: Rome2000

;’)


24 posted on 11/13/2014 7:56:43 PM PST by SunkenCiv (https://secure.freerepublic.com/donate/_______________________Celebrate the Polls, Ignore the Trolls)
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To: Zuben Elgenubi

http://en.wikipedia.org/wiki/Giotto_(spacecraft)

Measured volume of material ejected by Halley:
80% water,
10% carbon monoxide
2.5% A mix of methane and ammonia.
Other hydrocarbons, iron, and sodium were detected in trace amounts.


25 posted on 11/13/2014 8:01:28 PM PST by SunkenCiv (https://secure.freerepublic.com/donate/_______________________Celebrate the Polls, Ignore the Trolls)
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