Explanation:
As humans explore the universe, the record for largest asteroid
visited by a spacecraft has increased yet again.
Earlier this month, ESA's robotic
Rosetta spacecraft zipped past the asteroid 21 Lutetia
taking data and snapping images in an effort to better
determine the history of the asteroid and the origin of its
unusual colors.
Although of unknown composition,
Lutetia is not massive enough for gravity to pull it into a sphere.
Pictured above on the upper right, the 100-kilometer across
Lutetia is shown in comparison with the other nine asteroids and four comets that have been visited, so far, by human-launched spacecraft.
Orbiting in the main asteroid belt,
Lutetia
shows itself to be a heavily cratered remnant of the early Solar System.
The Rosetta spacecraft is
now continuing onto
comet Churyumov-Gerasimenko where a landing is planned for 2014.