space phenomena that could kill astronauts

So key investigations will involve looking for evidence of past – or possibly present – life and that is a whole new ballgame. Whereas the lunar samples of the 1970s were from a barren world, Mars could once have been a habitable planet. It will load them into a Nasa spacecraft known as the Mars Ascent Vehicle, which will blast them to a rendezvous with the European supplied Earth Return Orbiter that will bring the samples to Earth. If all goes well, a European rover built at Airbus Defence and Space in Stevenage will arrive on Mars in 2028 to collect the canisters. To replicate this success for Mars, Perseverance is equipped with more than 30 canisters, into which interesting-looking rocks will be loaded and then cached on the surface. The value of sample return was demonstrated in the 1970s when the analysis of moon rocks brought back by the Apollo astronauts changed our understanding of the solar system’s history and formation.

If you discover signs of life on Mars, you want to know that’s Martian life And because laboratory techniques improve constantly, they can continue to be inspected year after year for new discoveries. Samples can be analysed much more thoroughly on Earth than using even the most sophisticated Mars rover. “Scientists really want rocks from Mars back on Earth,” says Gupta. Yet what makes Perseverance unique is that it is also the first part of an ambitious 10-year plan between Nasa and the European Space Agency (Esa) to bring Martian rocks to Earth in around 2031. As well as telling us about the history of the planet’s formation, those primeval rocks could also contain clues as to whether life ever began on the red planet. On Earth, the constant shifting of the crust has mostly destroyed the very first surface rocks to form, but on Mars the oldest rocks are preserved, so there is an unbroken record stretching back more than four billion years. “We want to get a fuller understanding of how Mars formed as a planet,” says Sanjeev Gupta of Imperial College London, who is part of the Perseverance science team.

It’s got a long list of science objectives to work through. On 18 February, around 8pm GMT, Nasa will attempt to land the car-size rover Perseverance in Jezero crater.

Space phenomena that could kill astronauts