A milestone of the Rosetta mission is about to take place next month with the landing of the Philae lander on the surface of comet 67P/Churyumov-Gerasimenko.
On Wednesday, the European Space Agency (ESA) announced that it has green-lighted the landing of the Philae on Rosetta's target comet on Nov. 12. The touchdown will be a historical event as it will be humanity's first attempt at landing an instrument on a comet.
The robotic lander will descend to a spot known as "Site J," which is located at the head of 67P/C-G and which was selected earlier in October because it poses minimal risks to the lander compared with other landing sites that were considered. It also offers what scientists described as "unique scientific potentials."
With Site J as its touchdown site, Philae will separate from Rosetta on Nov. 12 at 08:35 GMT at a distance of about 22.5 km. from the center of 67P/C-G and will land on the surface of the comet after about seven hours at around 15:30 GMT. Communication between Rosetta and Philae, however, will start earlier at two hours after the separation.
The Philae will capture images including its "farewell" image of the Rosetta shortly after separation. It will also take images as it descends into the surface of the comet. The first batch of these images will likely reach Earth several hours after the separation.
Although it appears that everything is already good to go, ESA said that there are still a series of critical decisions to make before Rosetta releases the lander and these include having Rosetta in the right trajectory. The mission may not be pushed through if the spacecraft is not in the right location and this could mean that the Rosetta mission team will have to revise the timeline again.
"There are still a number of key milestones to complete before we can give the final Go for landing," Rosetta mission manager Fred Jansen said. "If any of the decisions result in a No-Go, then we will have to abort and revise the timeline accordingly for another attempt, making sure that Rosetta is in a safe position to try again."
Philae is set to start conducting its first surface science experiments after about an hour after it has safely landed on the comet's surface.
Scientists hope that the Rosetta mission would shed light on the evolution of comets as well as give hints on the formation of the solar system and the origin of water on Earth.