Among the primary objectives of the European Space Agency's (ESA) Rosetta is to land a probe on the surface of comet 67P/Churyumov-Gerasimenko, where it had been in close proximity since early August.
Mission scientists and engineers appear to be busy making the necessary preparations for the landing of the 100 kilogram Philae lander, which is currently set to touchdown on comet 67P in November this year.
On August 25, ESA announced five potential locations for the lander's touchdown site and photos of these sites were thoroughly examined by scientists for three weeks to identify possible operating and orbital strategies required for the Rosetta to land Philae on each of them.
To allow scientist to get detailed information about each of the possible landing sites, Rosetta, which rendezvoused with comet 67P at a distance of 100 km on Aug. 6, approached to about 50 km. to capture high definition photos of the comet's surface, which is characterized by high cliffs and depressions and may be potentially littered by hazardous fractures and boulders. The spacecraft also took temperature readings and pressure measurements of the comet's gas.
The candidate sites will have been evaluated and ranked on Sunday and ESA will reveal the prime landing and backup sites at the ESA Headquarters in Paris, France on Monday, Sept. 15. The space agency will also discuss the challenges associated with each of the sites and other scientific data it has gathered so far.
The Rosetta team pointed out that the exact landing location will be determined based on the relative position of the spacecraft and the comet when Philae is deployed as well as the direction and speed of the lander's deployment.
"The Rosetta and Philae operations teams can only predict the landing point in advance to within an ellipse typically 1 kilometre long on the surface of 67P/C-G," ESA's Rosetta blog explained. "This is larger than any of the apparently smooth terrains on the reachable parts of the surface of the nucleus, adding to the challenge of selecting the best possible site."
Philae's scientific work will commence as soon as it is released from the orbiter. During the separation, descent and landing (SDL) phase, which will last anywhere between 5 to 10 hours, many of the lander's instruments will already start taking and measuring data.
The Philae is expected to gather and relay information about the comet until March 2015. By that time, the temperature of the lander's compartment may have become too high for it to continue the operation.
