Asked by Carrie Davies
Astronauts could indeed land on a comet, however with low gravity and traveling at immense speeds, doing so would be very difficult.
Most comets tear through space at incredible speeds; typically many tens of thousands of miles an hour. In order to land you would have to perfectly match the spacecraft’s speed to that of the comet, and then ‘pull up’ to the comet to prepare for landing.
Having far smaller mass than the Earth, the gravity on the surface of a comet is much lower than on Earth, and so landing in the traditional sense would not be possible as you would bounce off the surface. Astronauts would need to harpoon the comet to reel the craft in towards the surface – just like the recent Rosetta mission.
Answered by Sophie Allan at the National Space Centre
Image Credit: ESA