They made Rosetta also moves so fast. "Violent" here is an exageration, as at the vacuum (or near-vacuum), if both objects are moving in the same direction and

They made Rosetta also moves so fast. "Violent" here is an exageration, as at the vacuum (or near-vacuum), if both objects are moving in the same direction and speed, relatively to each other they are very close to still... and calm.