Space probe performs Mars fly-by

A European space probe has completed a close fly-by of the planet Mars in a crucial manoeuvre on its 10-year journey to land on a distant comet.

The unmanned Rosetta craft passed within some 250 km (150 miles) of Mars.

In a precise move, the probe used the planet's gravity to change course on its voyage to the Churyumov-Gerasimenko comet out near Jupiter.

Rosetta is due to reach the comet's orbit in 2014 and send a lander to its surface to study its chemistry.

There is no technology to send the probe directly to the comet at the right speed.

So the craft must harness the gravitational forces of Mars and the Earth to propel it to the right place at the right velocity.

This was the first and only time Rosetta was to fly past Mars.

As expected, experts at the mission control centre in Darmstadt, Germany, lost contact with the probe as it went behind the planet for the 15-minute manoeuvre.

During this time, Rosetta had to rely for power on onboard batteries, as Mars blocked light to its solar panels.

As radio contact was restored, there was applause in the control room.

Spacecraft operations manager Andrea Accomazzo said the manoeuvre was "fundamental to the mission".

"It's a very big success, so we are very happy."

The probe will perform two similar fly-bys of Earth this year as it accelerates towards the comet.

The craft is named after the Rosetta stone, which led experts to decipher Egyptian hieroglyphics.

Scientists hope that this hi-tech Rosetta will, through its exploration of the comet, help solve some of the unexplained mysteries of the solar system and how it evolved.