NASA’s Mars 2020: What has the Perseverance Rover found in two years on Mars?

Two years ago NASA’s Perseverance Rover landed on the surface of Mars, marking the next step in the space agency’s Mars 2020 mission. This stage of the mission will investigate the history of and collect samples from the Red Planet.

On 18 February 2021 the six-wheeled rover arrived on Mars and has been conducting vital research into the planet’s history. The Perseverance mission is also the first stage of a NASA-European Space Agency initiative to bring back Mars rock samples for studying on earth.

Speaking on the eve of the mission’s two-year anniversary, Perseverance project scientist Ken Farley said: “Perseverance has inspected and performed data collection on hundreds of intriguing geologic features, collected 15 rock cores, and created the first sample depot on another world.”

“Anniversaries are a time of reflection and celebration, and the Perseverance team is doing a lot of both,” he added.

So after two years on the surface of Mars, what have we learnt from the ground-breaking mission?

Evidence of water uncovered by Perseverance Rover

The rover has spent much of the past two years in the Jezero crater, a vast geological feature that is around 28 miles in diameter. Jezero is an impact crater formed roughly 4 billion years ago and scientists hope that it will reveal a lot about the planet’s history.

Most excitingly, the crater’s western curve appears to be formed from an ancient riverbed that fans out into a dried delta. This geographical feature is real evidence that there has previously been liquid water on the surface of Mars.

Ken Williford, astrobiologist at the Blue Marble Space Institute of Science in Seattle, described the delta as a “flashing signpost beautifully visible from orbit that tells us there was a standing body of water here”.

Life-giving substances found on Mars

The Jezero crater has been the main focus of Perseverance’s investigation and researchers has been able to conduct remote tests on the substances found along the suspected delta. It is thought that water used to flow into a lake spanning much of the crater and evidence of water has been found in the ground.

NASA scientists have identified sulfates and other mineral in the crater. These substances can only be formed with the presence of water.

The mission has also studied sedimentary rocks present in the delta, which are most likely to contain trace amounts of chemicals that have been there in the past. One of the most notable discoveries has been the existence of carbonates in the grounds. Carbon has been described by the NOAA as the “chemical backbone of life on Earth,” so finding levels of carbon in the ground could suggest a history of life on Mars too.

Volcanic rocks could give clue to the crater’s evolution

Sedimentary rock has the greatest chance of preserving chemical samples, but researchers were also struck by the presence of igneous rock. On Earth igneous rock is formed when molten rock solidifies, most typically around active tectonic plates or in the aftermath of volcanoes.

Perseverance found evidence of volcanic rock present in the Jezero crater, suggesting that lava may have flowed into the lake at some point in its ancient past. Alternatively the rock identified could have been transported from elsewhere on the planet, possibly due to running rivers.

In essence this finding suggests that Mars has had a more varied and diverse geographical history than had previously been assumed.