Rosetta spacecraft passes Lutetia asteroid

July 12, 2010

The unmanned made its closest approach to the  Saturday. Rosetta flew within 3,162 kilometers of the asteroid. The spacecraft took high-resolution photos and searched for traces of an atmosphere and magnetic effects. It also studied the composition and mass of the asteroid.

"As Rosetta drew close, a giant bowl-shaped depression stretching across much of the asteroid rotated into view," said Holger Sierks of the, "The images confirm that Lutetia is an elongated body, with its longest side around 130 kilometers. I think this is a very old object. Tonight we have seen a remnant of the Solar System's creation." Around 400 photographs were taken during the flyby; however, it will take several days for in-depth data to be transferred to Earth.

"Little is known about asteroid Lutetia other than it is about 100 kilometers (62 miles) wide," says American project scientist Claudia Alexander, "Allowing Rosetta's suite of science instruments to focus on this target of opportunity should greatly expand our knowledge of this huge space rock, while at the same time giving the mission's scientific instruments a real out-of-this-world workout."

The Lutetia asteroid is the largest asteroid yet visited by a spacecraft. Throughout its 4.5 billion year lifespan, its surface has been bombarded repeatedly by other space debris. Very little is known about the asteroid and scientists hope that this flyby will help determine the asteroid's origin. They hope to make their findings public at the Europlanet conference in Rome, Italy, late this September.

The Rosetta spacecraft, a project led by the, flew by the asteroid on its way to the. Launched in 2004, the spacecraft is expected to arrive at its final destination in 2014. Once there, it will deploy the to explore the comet's surface. The spacecraft's visit to this asteroid marks the final major scientific milestone before it is put into hibernation mode to be reactivated in 2011.