6 October 2008
The MESSENGER probe flew by Mercury for the second time last night, coming only 200 km from the planet’s surface. Since MESSENGER is so close to the sun, NASA engineers had to compensate for the fact that the intense sunlight produces a force on the spacecraft. In essence, MESSENGER was acting like a small solar sail! The picture shown above was taken yesterday during the approach, but I’ll post the new images as soon as possible. In the meantime, go check out this video, showing a simulation of the flyby and indicating which science observations happened when. Also, check the Planetary Society Blog for lots more info.