Rosetta is an amazing probe launched by the European Space Agency. In 2014 it will go into orbit around the comet 67P/Churyumov-Gerasimenko, and actually deploy a lander to sample the surface!
That rendezvous is still years away, but the target is now in sight: Rosetta has returned its first image of the comet.
Oh, very cool! The top image is the wide angle shot, showing a densely-populated star field toward the center of our galaxy; from Rosetta that's the direction to the comet. The second image zooms in a bit, and you can see some distant stars and nebulosity. The bottom one has been processed to remove the stars, and the nucleus of Churyumov-Gerasimenko stands out.
Note that this image was taken when Rosetta was still 163 million kilometers (100 million miles) from the comet -- that's more than the distance from the Earth to the Sun! That's why it took a total of 13 hours of exposure time to see the comet in these images; it's still extremely faint from that great distance.
These pictures are important for several reasons: they test the cameras, a critical event for the upcoming encounter; they provide navigation cues, allowing engineers to test if the position of the comet is where they expected it to be; and they give the scientists and engineers practice in dealing with the images from the probe.
Not that Rosetta has simply been coasting along; it's passed by the Earth, Mars, and even two asteroids -- Lutetia (see the gallery below of those spectacular images!) and Steins -- returning incredibly lovely pictures of these worlds.
Rosetta is already a very successful mission, and the best is yet to come.
Image credit: ESA 2011 MPS for OSIRIS-Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA
Image gallery of Rosetta's flyby of the asteroid Lutetia
- Ten Things You Don't Know About Comets
- Rosetta takes some home pictures
- Earth from Rosetta
- Rosetta swings by Mars