ExoMars: Scientists brace for 'six minutes of terror'

Mars gets a visitor. Photo / AP

British scientists will face "six minutes of terror" this week as the Schiaparelli space probe plunges to the surface of Mars after a seven-month journey.

The ExoMars spacecraft carrying it, which launched in March, was to arrive at the Red Planet early today after a 480 million km journey, before the lander begins its descent to the surface on Thursday.

It will not all be plain sailing. The lander has to enter the Martian atmosphere at exactly the right angle and carry out a series of operations, timed to the second, if it is to get to the surface in one piece. If it is successful and begins transmitting signals, it will be the first time a European mission has landed successfully on a planet.

Although the ill-fated Beagle 2 probe made it to the surface of Mars in 2003, its solar panels failed to open after impact, rendering it paralysed and unable to contact Earth. This time, the scientists are taking no chances.

The mission - part of ExoMars, a European Space Agency project searching for life on Mars - is in two parts, with Thursday's landing acting as a dummy run for the launch of a European rover in 2020 that will hunt for alien life.

The probe's battery will operate for only a few days, but the main point of the mission is to see whether it can be brought down safely, with all its instruments intact.

Dr Stephen Lewis, of the Open University, who co-heads the team that will receive the data, said: "This is really a test to see if we can land on Mars. We are learning how to do it and seeing if we have all our calculations right.

"It will be nerve-racking six minutes of terror, and by that stage there is nothing anyone can do if things go wrong, and there are 100 things that need to go right.

"These are incredibly complicated machines, and everything has to work, so all you can do is cross your fingers.

"There is also danger that a probe could bring bacteria from Earth. It would be dreadful if we sent a rover up looking for life and the readings were tainted by microbes we brought ourselves."

Once on the surface, instruments will sample the humidity and dust at the landing site. Touchdown is close to Nasa's Opportunity rover and there is a chance the robot will capture a photograph of the probe coming in to land.

Mars is thought to be the best chance of finding evidence of extraterrestrial life because it once had running water and an atmosphere.

The hope of discovering life was raised in 2014 when methane was recorded by Nasa's Curiosity rover. In the new book Aliens, Professor Monica Grady, of the Open University, said methane could provide evidence of life on Mars.