Article Posted on : - Jun 16, 2010

Rosetta's encounter with asteroid Steins in 2008. An ESA Photo

PARIS (BNS): European comet chaser Rosetta will zoom in on asteroid Lutetia next month, taking images of the cosmic object lying in the main asteroid belt between Mars and Jupiter which will help astronomers determine its true shape, size and composition.

The face-off between the European Space Agency’s spaceship and the asteroid will occur on July 10, 2010 when Rosetta will flyby within 3,200 km of the space rock. The encounter will last for nearly two hours during which Rosetta will take the asteroid’s images and beam it back to Earth immediately, ESA said.

The spacecraft started taking navigational sightings of Lutetia at the end of May to help ground controllers determine any course corrections required to achieve their intended flyby distance.

Next month’s encounter with Lutetia will provide a true picture of the asteroid which appears as a single point of light to ground telescopes. The continuous variation in its brightness suggests that Lutetia is rotating and has an uneven surface.

Scientists have given differing estimations of the asteroid’s size. It is believed to be quite primitive, left on the shelf for billions of years because no planet consumed it as the Solar System formed. Indeed, most measurements appear to back this picture, making the asteroid out to be a ‘C-type’, which contains primitive compounds of carbon.

However, some measurements suggest that Lutetia is an ‘M-type’ which could mean there are metals in its surface.

Rosetta's ‘blind date’ with Lutetia is expected to solve all the mystery surrounding the asteroid.