[meteorite-list] 2014 Preview: First Touchdown on a Speeding Comet (Rosetta)

[Ron Baalke]

http://www.newscientist.com/article/mg22029484.800-2014-preview-first-touchdown-on-a-speeding-comet.html

2014 preview: First touchdown on a speeding comet
by Stuart Clark
New Scientist
23 December 2013 

In 2013, comet ISON flew into our skies. In 2014, we will return the favour 
when the European Space Agency's Rosetta craft begins orbiting comet Churyumov-Gerasimenko 
and touches down on its surface. That would mean two firsts for comet 
exploration - plus the most ambitious deep-space landing ever attempted.

Rosetta is a veteran traveller. Launched in March 2004, it has spent a 
decade looping around the sun, gaining momentum - and passing two asteroids. 
Its target travels at about 16 kilometres per second, and Rosetta is now 
catching the comet by 800 metres each second.

The craft has been a virtual zombie since June 2011 to preserve its resources, 
with only a flicker of power to keep its computer brain alive. The alarm 
clock is set for 20 January 2014, when Rosetta will wake up to prepare 
for a May rendezvous with Churyumov-Gerasimenko.

Though NASA's StarDust mission flew through the tail of comet Wild2 in 
2004, no craft has ever orbited one. Rosetta will orbit its target at 
a leisurely walking pace, searching for a landing spot. Things will get 
even more exciting in November, when the robotic lander Philae (illustrated) 
detaches from the mother ship and becomes the first spacecraft to land 
on a comet.

Philae will anchor itself with a harpoon before starting to dig. An on-board 
lab will analyse the scoops of rock and beam the results to Earth. Like 
asteroids, comets are thought to preserve material from the birth of the 
solar system, 4.6 billion years ago. Comets contain water, so the chemistry 
of the scoops could reveal whether our oceans, and a bunch of molecules 
necessary for life, came from comets smashing into early Earth.

Rosetta's final task will be to monitor the continual disintegration of 
Churyumov-Gerasimenko as it makes its closest approach to the sun on 13 
August 2015.