Paris, September 9 : The first images of asteroid Steins, from Rosetta's OSIRIS imaging system and VIRTIS infrared spectrometer, have been derived from raw data and delivered spectacular results, the major revelation being that the asteroid looks like a diamond in the sky.
"Steins looks like a diamond in the sky," said Uwe Keller, Principal Investigator for the OSIRIS imaging system from the Max Planck Institut Fuer Sonnensystemforschung, Lindau.
Visible in the image are several small craters on the asteroid, and two huge ones, one of which is 2 km in diameter, indicating that the asteroid must be very old.
The images are 50 to 60 pixels in diameter, enough to characterize the shape and other characteristics of the body of the asteroid.
According to Rita Schulz, Rosetta Project Scientist, "In the images is a chain of impact craters, which must have formed from recurring impact as the asteroid rotated. The impact may have been caused by a meteoroid stream, or fragments from a shattered small body."
The chain is composed of about 7 craters. To determine the age of the asteroid, a count of the craters on the asteroid's surface has been started. So far, 23 craters have been spotted.
From the images, scientists will try and understand why the asteroid is unusually bright, and how fine grains of the surface regolith are. This will tell them more about how the asteroid formed.
After analysis of the Rosetta data, Steins will be one of the best-characterized asteroids so far.
"It looks like a typical asteroid, but it is really fascinating how much we can learn from just the images. This is our first science highlight; we certainly have a lot of promising science ahead of us. I'm already looking forward to encountering our next diamond in the sky, the much bigger Lutetia," said Gerhard Schwehm, Mission Manager for Rosetta.