Engineers plan to collect rocks on Mars and bring samples to Earth, in one of the most complex robot space projects envisaged. The scheme, being developed by Nasa and the European Space Agency (Esa), will involve robot rovers finding rocks that might contain evidence of past life
The samples would be blasted into space, intercepted by an unmanned spacecraft, and dropped by parachute in the Utah desert, with the 500g of Martian soil and rock shared with researchers round the world.
Nasa recently gave outline approval for such a mission – which will cost billions of pounds – and research ministers from Esa’s member states will meet in Seville this week to decide if they will support it. The UK is a leading partner in Esa
“The Mars Sample Return is a key part of our future exploration programme, and I very much hope Europe’s science ministers will back it,” Jan Wörner, Esa’s director general, said last week. “However,
we should be clear that every step of the mission is going to be very challenging.”
Scientists are keen to study Martian rock as conditions on the red planet billions of years ago were similar to those on Earth. It had a thick atmosphere and running water on its surface.
Scientists are keen to study Martian rock as conditions on the red planet billions of years ago were similar to those on Earth. It had a thick atmosphere and running water on its surface.
Today, most of its atmosphere has gone and researchers want to know if life evolved before that. Hence their search for fossil microbes.
“We have only two ways to study Martian soil and rock at present,” said Open University astrobiologist Susanne Schwenzer. “We can send probes to Mars and analyse rock samples there or we can study bits of Mars that arrive on Earth as meteorites.”
But space probes are constrained by power supplies, data storage, the harsh Martian environment, the need to miniaturise equipment, and difficulties in landing on Mars.
By contrast, studying meteorites – bits of rock blasted into space when larger meteorites have struck Mars and thrown up debris – poses different problems. Schwenzer said: “They often get contaminated after their arrival on Earth and it is not known where on Mars they originated
The answer, say scientists, is to bring Martian rock and soil to Earth, to study it using the world’s most advanced laboratory equipment
The mission will start by using the new Nasa Mars 2020 rover, which is set to land in Jezero crater in the Syrtis Major region of Mars in 2021
The mission will start by using the new Nasa Mars 2020 rover, which is set to land in Jezero crater in the Syrtis Major region of Mars in 2021
“Mars 2020 will collect soil samples, put them in small metal tubes, then seal them,” said Sanjay Vijendran, a lead member of Esa’s Mars Sample Return team. “Caches of these tubes will then be left at designated sites on the Martian surface.”
Then a second craft to be built by Esa, known as a fetch rover, will land on Mars, trundle round these sites, and load the samples into a football-sized canister. This will be taken to a US rocket that will blast the container into orbit round Mars.
A robot spaceship called the Earth-return orbiter will sweep round Mars, capture the canister, then head back to Earth, before releasing the capsule so that it lands on the Utah desert.
Lewis Dartnell, an astrobiologist at the University of Westminster, London. said: “The mission involves an incredibly complex sequence of manoeuvres, and there’s so much that could go wrong.
However, if we want to find evidence that there was once life on Mars, this is the sort of thing we are going to have to do. It will be worth the effort.”
The prospect of finding past life on Mars excites scientists. However, there is also a chance that life still exists there. So researchers will have to take considerable care that the capsule does not carry potentially dangerous micro-organisms.
