A reconstruction of the rover amid a Martian landscape.

The Perseverance rover heading for Mars will collect rock samples of interest and then leave them to be returned to Earth at a later date © NASA

Read later

Beta

During Beta testing articles may only be saved for seven days.

Mars 2020: Perseverance rover has landed

The Mars 2020 rover landed near the Jezero Crater on 18 February 2021.

After eight months hurtling through space, the Mars Perseverance rover has successfully landed and begun its mission. This is NASA's first major return to Mars since the Curiosity rover landed in 2011.

Prof Caroline Smith, Head of Collections for Earth Sciences at the Museum, has been working on the mission. She describes how the Museum's expertise in planetary science, geology and searching for evidence of life, and collecting samples can make a contribution to this exciting mission. 

The journey so far

Travelling at speeds of 79,000 kilometres per hour and across approximately 470 million kilometres, it has taken the Perseverance rover nearly eight months to reach its destination.

The landing process is always a challenge - more than two thirds of missions sent to Mars have failed in their descent into the planet's thin atmosphere.

Perseverance is specially adapted to land successfully, however. On entry, it shed its cruise stage, which includes solar panels, radios and fuel tanks, then used a parachute and rockets to slowly lower itself onto the planet's surface.

Its exterior aeroshell protected it from the high temperatures caused by entry into Mars' atmosphere and which caused the outside heatshield to reach temperatures of 1,300°C. Finally, a 'sky crane' system, similar to that used on the Curiosity rover, ensured that it safely reached the surface.

The team back on Earth endured a wait to find out if the landing was successful. It can take up to half an hour to know if all is well. Caroline describes the entry, descent and landing as 'seven minutes of terror' while UKSA Aurora Fellow Keyron Hickman-Lewis refers to this moment as 'seven minutes of anticipation', adding that it is 'decades of work held in a small window of time'. 

This is a career highlight for engineers and scientists involved, as many have been building up to this mission for their entire careers. Caroline comments that the mission is 'the result of much hard work, over many years by friends and colleagues', a testament to the close bonds forged around the rover.

Mars viewed from space, showing its orange colour with two white poles.

Mars has long been on interest in the search for extraterrestrial life because we know that it once had seas of liquid water covering its surface © NASA 

What is the Perseverance doing on Mars?

The rover's first few days were spent carrying out safety checks. Its landing was directed near the sedimentary deposits on the delta in the Jezero Crater.

Ideally, scientists wanted it near the delta but not too far away or too close. Landing directly onto the Delta makes it harder to see the deposits, while too far away and the mission loses time steering the rover to the correct place. Keyron says the team have had 'operational readiness training' so that they were prepared for any scenario.

Perseverance will drill for interesting rock samples that show different features to help understand the geology of Jezero Crater. The team also hope to find rocks containing biosignatures, which are fossilised chemical and textural residues of life that can be found in sedimentary rocks. Caroline hopes that they can be returned to Earth as soon as 2031, saying, 'we are in the best place we've ever been to get Mars samples back from Mars'.

This opportunity to collect samples is exciting: the Martian rock samples we have on Earth in the form of meteorites are all igneous rocks. The volcanic nature of igneous rocks makes them unsuitable for preserving traces of life, unlike sedimentary rocks, which are better at retaining fossil traces. 

Computer generated picture of Perserverance on Mars, drilling into the red rock.

The different payloads on the Perseverance rover will help it to analyse the rocks and mineralogy of the planet down to chemicals and elements that are present © NASA

How is the Museum helping with research?

Physical samples may not return to Earth until 2031, but Perseverance's cameras allow scientists to examine the surface of Mars almost immediately. These images will give them insight into the geological history of Mars and help them to understand whether the planet holds physical or chemical evidence of life.

For Keyron, the first image data returned is the most exciting part of the landing. He says, 'At the moment of landing we'll be waiting intently for the images.'

Habitability on Mars has similar a timeframe to that on Earth, as during its earliest history, Mars also had liquid water. Scientists hope that by examining fossil evidence through the textures of Martian rocks, they could see whether the planet has ever supported life.

Keyron's specialism is Archaean microbial palaeontology and early surface environments and ecosystems. He examines the fragmentary record left by simple organisms found in rocks which date from when there was no oxygen on Earth.

The age and state of preservation of these rocks make this a difficult area of study. 'It can sometimes be hard to tell if it even is a fossil,' Keyron says, but his research gives us a framework for studying the rocks. Earth and Mars share a history within the solar system, so if Mars were habitable then it could at one point have had similar conditions as Earth when it comes to harbouring life.

The Museum is returning a small sample of one of its own Martian meteorites, Sayh al Uhaymir (or SaU 008), to the red planet. This specimen will help the SHERLOC instrument -a tool for exploring Mars which uses spectrometers, a camera and a laser - test that it is working as expected and that the data it collects on Mars is accurate. This meteorite was chosen because it is tough enough to survive the landing.

 

A satillite image of the Jezero Crater, showing the lines of an old river carved into the rock leading to what was once the river delta.

The Jezero crater was chosen as the landing site as it shows evidence that there was once a river delta flowing into a lake © NASA

Current plans are for Perseverance to collect and store samples until a later mission is sent to retrieve them in 2028. These samples are then planned to return to Earth in 2031.