Artist’s impression of asteroid Steins from the perspective of the spacecraft.
The Rosetta spacecraft will fly by asteroid Steins in Autumn 2008. Closest approach will be on September 5, 2008 at 18:37 UT at which time the spacecraft will be 800 km from the asteroid. The relative speed will be 8.6 km/s.
The planned fly-by strategy allows for continuous observation of the asteroid before, during and after closest approach and has been optimised for low closest approach and for a large phase angle coverage (from 0 to 140 degrees). Credit: ESA