Rosetta’s Philae lander given “green light” for upcoming landing
The European Space Agency (ESA) has officially given the go ahead for Rosetta’s lander, Philae, to touchdown on comet 67P/Churyumov-Gerasimenko. The historic landing is now scheduled to occur on Nov. 12, and will mark the first time a spacecraft has landed on the surface of a comet. The chosen landing site, designated “Site J”, is on the head of the comet and was selected after extensive analysis of five different sites.
Rosetta launched a decade ago, and arrived at its destination back on Aug. 6. Since its arrival at the comet, Rosetta has steadily moved closer and closer to 67P, capturing unprecedented views of the comet. Comets are described as cosmic time capsules, and scientists believe they are the key to understanding how the the early solar system formed.
Currently Rosetta is 6 miles (10 kilometers) from the center of the comet, but will be orbiting at a distance of 14 miles (22.5 kilometers) at the time of touchdown. It’s imperative the spacecraft back up prior to landing, in order to properly observe both the primary and the back-up landing sites. Rosetta will be scouting for any potential hazards prior to touchdown.
At 3:35 a.m. EST (0835 GMT) on Nov. 12, Rosetta will release Philae, and landing will occur approximately seven hours later. The landing process is a fully autonomous process, with ESA supplying instructions to the spacecraft and the lander prior to release. It take 28-minutes for the signal from Rosetta to reach us here on Earth, so ESA expects to receive landing confirmation at 11:00 a.m. EST (1600 GMT).
“Now that we know where we are definitely aiming for, we are an important step closer to carrying out this exciting — but high risk — operation,” said Fred Jansen, ESA’s Rosetta mission manager. “However, there are still a number of key milestones to complete before we can give the final Go for landing.”
On Nov. 11, in the final hours leading up to separation, the final Go/No-Go poll will be conducted. Flight dynamics will verify the spacecraft is in the proper trajectory following one last maneuver. This final flight maneuver will occur approximately two hours prior to separation. After separation, Rosetta will move away from comet 67P to ensure they can communicate with the lander. If by chance, the final poll results in a “No-Go”, then the team will have to regroup.
Jansen went on say, “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 Rosetta is in a safe position to try again.”
Philae’s descent will span seven hours, and the lander will taking photos, as well as conducting science experiments. Philae will gather data on dust, gas, and plasma samples. An hour after touchdown, Philae will begin its primary science mission. The mission will last approximately 64-hours, depending on how well the batteries last.
As Philae and the comet travel closer to the Sun, the lander will continue to conduct science experiments. Rosetta scientists will be watching the lander close to see how the batteries recharge, and how cometary dust affects the solar panels. Currently, Philae is expected to remain functional until March 2015. However, the Rosetta orbiter is expected to last longer and will follow the comet’s approach to the Sun.
Make sure to stay tuned to SpaceFlight Insider for more details on this historic mission. A final timeline of the events of separation and landing will be released soon.
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