Beamed back: asteroid up close

22:34, Sep 03 2012

Nasa's Dawn spacecraft is about to leave the vicinity of giant asteroid Vesta on its way to its second target in the main asteroid belt, the dwarf planet Ceres.

With Dawn's mission to Vesta now at an end, Nasa has published an animation of a simulated flyover of the giant asteroid based on images taken by cameras on the spacecraft.

Viewers are taken over some of Vesta's most intriguing landmarks, seen up-close by Dawn for the first time.

Dawn set off on its five billion km mission in 2007 and remains on track to become the first probe to orbit and study two distant solar system destinations.

It arrived at the 578km by 560km by 458km Vesta in July 2011 and will reach the 975km by 909km Ceres in early 2015.

It will spiral away gently from Vesta on its ion propulsion system, which uses electricity to ionize xenon to generate thrust, Nasa said.

While the 30cm wide ion thrusters provide less power than conventional engines, they can maintain thrust for months at a time.

Dawn's orbit around Vesta revealed unprecedented detail about the asteroid, showing Vesta completely melted in the past, forming a layered body with an iron core.

Scarring was also revealed from two colossal collisions in the past two billion years. The impacts sculpted dramatic troughs around the asteroid.