In order to thoroughly conduct a study of the comet 67P/Churyumov-Gerasimenko, the Eueropean Space Agency's Rosetta, which was launched for mission ten years ago and finally arrived 100 km, away from its target comet in Aug. 6 this year, was to land a probe on the comet's surface.
The Philae lander, a small robot with an army of instruments for taking measurements, high-definition photos and other scientific data from the planet, will gather vital information to be relayed for analysis and study on Earth. Scientists, however, realized that choosing a landing site for the lander is trickier than previously believed because of the comet's potentially hazardous characteristics such as its rugged terrain.
The ESA has come up with five potential landing sites last month, which were individually assessed for three weeks, but finally on Monday Sept. 15, scientists have finally revealed the touchdown location for the Philae. Scientists said that the site offers the best option among the candidate sites given the challenges associated with landing down the probe on Comet 67P's surface marked dangerous cliffs, depressions, fractures and boulders.
"There is flat area, but there is also some rough terrain," Stephan Ulamec, Philae lander manager at the German Aerospace Center described the site. "It's not a perfectly flat area as we probably would have hoped for a safe landing site."
The landing area called "Site J" is located at the head of comet 67P and which appears to provide unique scientific potentials. It also poses minimum risks to the robotic lander compared with other candidate locations albeit it is near active gassy pits.
ESA also identified the backup location, "Site C", which is on the "body" of the charcoal-black and irregularly shaped comet. The other site that was considered as backup was "Site B" but Site C was eventually chosen because of its higher illumination profile and it has fewer boulders.
Philae Lander Manager Stephan Ulamec, from the DLR German Aerospace Center, said that the shape of the comet has made it "operationally challenging" but while none of the five potential touchdown sites fully met the operational criteria, he said that it was clear Site J offers the best solution.
"Site J in particular offers us the chance to analyze pristine material, characterize the properties of the nucleus, and study the processes that drive its activity," said lead lander scientist Jean-Pierre Bibring, from the Institut d'Astrophysique Spatiale (IAS) in Orsay, France.
The touchdown is currently planned on Nov. 11 but the landing date will be confirmed by Sept. 26.
