European comet probe set to lift off

The European Space Agency’s ambitious mission to chase down a comet and land a probe on its surface was due to blast off today.

The €900m project, delayed by a year after a rocket exploded, was expected to launch from Esa’s Kourou spaceport in French Guiana at precisely 7.36am and 49 seconds.

Experts hope the epic 12-year mission will shed light on the origins of the solar system, the make-up of comets, and even the beginnings of life on earth.

The Rosetta craft, much of which was built by EADS Astrium in Stevenage, will take 10 years to reach comet Churyumov-Gerasimenko in May 2014.

It will then begin the most detailed observations of a comet ever made, becoming the first spacecraft to orbit a comet and the first ever to land on the surface.

The unmanned probe will build up momentum for its trek through the solar system by harnessing energy from a series of “gravitational slingshot” manoeuvres around the sun and planets.

Once Rosetta has reached the comet it will orbit its solid heart, or “nucleus”, before dropping the lander named Philae, to the surface.

John Ellwood, Esa’s Rosetta project manager, described the challenges of such a precarious mission.

“It is absolutely mind-blowing when we think about what we’re trying to do,” he said.

“It is an amazing challenge. We have got to press technology to the edge to do it.”

Philae will examine the dust and ice make-up of Churyumov-Gerasimenko while taking the first ever pictures from the surface of a comet.

The main Rosetta orbiter will spend the following months observing gasses and dust jets that burst from the nucleus and form the comet’s characteristic tail as it heats up on its way towards the sun.

Dr Gerhard Schwehm, one of the Rosetta scientists said the mission could help uncover the mystery of how life on earth began.

He explained that comets have complex organic molecules which some experts believe could have been “seed particles” dropped from a passing comet onto the earth that started life.

The mission is extremely difficult and fraught with potential hazards.

Rosetta will have to navigate its way through a belt of asteroids and will need to reach speeds of about 80,000mph to catch the comet.

Findings its target has been likened to trying to land a 12 inch ruler on the top of Nelson’s head in Trafalgar Square when you have the whole of London to aim at.

Mission controllers were hopeful that the launch would go ahead today but were keeping a careful eye on the weather conditions as storms, lightning and strong winds can arrive suddenly.

Rosetta will be carried into space by an Ariane 5 rocket but the mission involves a particularly complicated launch.

Scientists on the ground will have an anxious wait for one hour 45 minutes while the rocket carrying Rosetta orbits the earth once before blasting further into space.

This delayed ignition of what is known as the rocket’s upper stage has never been done before in this situation.

The Rosetta mission was originally planned for launch in January last year but was delayed after an Ariane 5 exploded just minutes after taking off.

The investigation grounded all Ariane 5 launches and Rosetta’s original target comet, Wirtanen, had to be abandoned.