Spacecraft safely enters Mars orbit

This undated Nasa artist's conception shows the Mars Reconnaissance Orbiter (MRO) that will make high-resolution measurements of the surface of the Red Planet from orbit. PHOTO: AFP

But other challenges lie ahead.

Next month, the two-ton orbiter will begin another critical phase in its $720 million mission. It will spend seven months dipping into Mars' upper atmosphere to shrink its current elliptical orbit to a circular one, which will take it as close as 200 miles above the surface.

The purpose is to get as close to Mars as possible to beam back detailed images.

"We got the capabilities that will knock your socks off," said project scientist Richard Zurek.

The Reconnaissance Orbiter joins Nasa's Mars Global Surveyor and Mars Odyssey and the European Space Agency's Mars Express, which already fly around the planet. On the surface, the Nasa rovers Spirit and Opportunity continue rolling across the planet.