The Proton-M rocket, carrying the ExoMars 2016 spacecraft to Mars, blasts off from the launchpad at the Baikonur cosmodrome, Kazakhstan / REUTERS/Shamil Zhumatov

The mission has echoes of Beagle 2 – but hopes to avoid the same fate

An experimental probe is about to land on Mars – scientists hope.

If the Schiaparelli lander successfully finds its way to the surface it will be the second European craft to do so. But that will just be the beginning of its mission.

The European Space Agency’s new mission recalls the landing of the Beagle 2 lander on the planet in 2003. That made its way to the surface, but it failed to properly open when it did so – leading scientists to lose contact with it.

Once it does land, and if everything goes to plan, the lander will begin its work on the ExoMars mission. That intends to help establish whether or not there is life on the planet, and if the strange methane found on the surface comes from aliens or from something more everyday.

Schiaparelli will take images of Mars and conduct scientific measurements on the surface, but its main purpose is to test technology for a future European Mars rover. ESA's last attempted Mars landing with the Beagle 2 rover failed in 2003.

Schiaparelli is part of the ExoMars program, a joint venture between ESA and Russia's Roscosmos. Its mother ship, the Trace Gas Orbiter, is to analyze methane and other gases in the atmosphere. 

Scientists will go through a tense time as they watch the lander makes its way to the red planets surface – and wait to find out whether it’s done so without echoing the fate of the Beagle 2.

Mission controllers hope Schiaparelli, part of an ambitious joint European and Russian mission to search for evidence of life on Mars, will fare better but stress that landing on the planet is notoriously tricky.

British space scientist Dr Manish Patel, from the Open University, a member of the team that will be analysing data from the spacecraft, said: "It's certainly a tense time. I'm looking forward to an interesting night's sleep, or lack of it.

"The classic problem with Mars is its thin atmosphere. If you have a thick atmosphere, it naturally slows you down, and if there's no atmosphere, it's easy. But Mars has a very thin atmosphere that slows you down a bit, but can still cause a lot of problems. It varies a lot; you get waves and ripples which are unpredictable.

"Dust impacting on the heat shield can also be a hazard, but I'm told that's one that can be compensated for."

Schiaparelli hitched a ride to Mars on the ExoMars Trace Gas Orbiter (TGO) spacecraft, crossing a distance of 500 million km (310 million miles) on its seven-month journey from Earth.

The probe parted company with its mothership on Sunday. It is due to enter the Martian atmosphere at around 3.42pm on Wednesday, travelling at roughly 21,000 km/h (13,050 mph).

Although it carries some instruments, Schiaparelli's main job will be to test out the landing system for a future ExoMars rover mission due to be launched in 2020.

Initially slowed by the friction on its heat shield, the probe will deploy its parachute at altitude of about 11 km (6.8 miles). As it nears the ground, three clusters of retro rockets will fire, slowing the craft's speed to less than 7km/h (4.3 mph) two metres (6.5ft) from the surface. The rockets will then switch off, allowing the probe to drop the rest of the way.

A special crushable structure built into the spacecraft will cushion against the final shock.

During the descent Schiaparelli will take pictures of the approaching Martian terrain.

The landing site is Meridiani Planum, a flat region that interests scientists because it contains an ancient layer of haematite. On Earth, the iron oxide mineral almost always forms in a watery environment.

Schiaparelli will spend up to about four days gathering weather data before its batteries run out.

While the landing is taking place, TGO will settle itself in orbit around Mars.

Starting next year, the orbiter will sniff the Martian atmosphere for traces of methane and help scientists decide if it has a geological or biological origin. On Earth, methane is chiefly produced by billions of bacterial organisms, many of which live in the guts of animals such as cows.

ExoMars Rover will deploy a six-wheeled mobile laboratory to the surface of Mars to drill into the soil and look for definitive signs of past or present life.

Additional reporting by Press Association