Europe’s pioneering Rosetta mission will conclude next week with an audacious piece of deep space parking.
The Rosetta mission has been studying comet 67P Churyumov-Gerasimenko since its arrival there in August 2014. In November of that year it captured the world’s imagination by placing the Philae lander on the icy surface. Now it is time for Rosetta to attempt a landing to bring the mission to a close.
Overnight on 29-30 September, operators will send a final sequence of commands to the spacecraft. An engine burn will then remove almost all of the spacecraft’s orbital energy, and it will begin a leisurely almost 15-hour drop from a height of 20km.
During the descent, its initial speed of just 30cm per second will be tripled by the weak gravitational field of the comet. At the moment of impact, Rosetta will hit the surface at walking speed. This is about the same speed that Philae touched down with.
The spacecraft will undoubtedly tumble, as it has no anchoring mechanism, and there is no chance that it will survive the impact.
The European Space Agency has decided to end the mission this way for two reasons: first that it stops Rosetta becoming a piece of floating space debris, and second, that it allows scientists to have a really close-up look at the comet.
Rosetta will descend towards a region containing a pit that appears to be where the comet releases dust and gas into space. On its way down, the Osiris onboard camera will attempt to see inside the pit to look for clues to the comet’s geological history.
The final touch-down is expected to be confirmed here on Earth on 30 September at around 12:20 BST.
