This has never been done before: the European Space Agency (ESA) is about to land a spacecraft onto the surface of a comet. Launched in 2004, the Rosetta spacecraft will reach 67P/Churyumov-Gerasimenko in August 2014, and will attach its Philae (fee-LAY) robotic lander to it during the following November.
The spacecraft’s mission is to study the comet at close-range as it transforms from a quiet nugget of ice and rock, frozen solid by years spent in deep space, to a sun-warmed dynamo spewing jets of gas and dust into a magnificently evolving tail…
“A flyby is just a tantalizing glimpse of a comet at one stage in its evolution,” points out (project scientist Claudia) Alexander. “Rosetta is different. It will orbit 67P for 17 months. We’ll see this comet evolve right before our eyes as we accompany it toward the sun and back out again.”
Because a comet has little gravity, the lander will anchor itself with harpoons. “The feet may drill into something crunchy like permafrost, or maybe into something rock solid,” Alexander speculates.
Once it is fastened, the lander will commence an unprecedented first-hand study of a comet’s nucleus while Rosetta continues to monitor developments overhead.
Update: This NAVCAM image was taken on August 2, 2014 from 500km (310.7 miles) away from the comet. Credits: ESA/Rosetta/NAVCAM
In the archives: What makes up a comet?