As the UAE’s Hope spacecraft continues its journey to Mars, an Abu Dhabi-based scientist has proposed that there could be underground life on the Red Planet.
The bombardment of Mars by high-energy particles called galactic cosmic radiation could power subsurface life, according to Dr Dimitra Atri of New York University Abu Dhabi.
Observations indicated there is underground ice and salt water on Mars, suggesting the “less harsh” subsurface environment, perhaps two metres down, could host life even if there was none above ground.
The presence of micro-organisms below the surface of Earth is another factor pointing to the possibility of underground life on Mars.
“A few years ago there was a discovery in South Africa in a gold mine about 2.8 kilometres deep. There’s a bacterium that lives off radioactivity,” said Dr Atri.
Using water and sulphur found underground, and powered by naturally occurring radioactivity from uranium minerals, the bacteria produce chemicals they use as food.
Dr Atri said micro-organisms beneath Mars’ surface could be doing something similar, living underground because the present-day thin atmosphere of Mars is not conducive to life.
“[Life] may have originated, and over a period of time the atmosphere eroded, the place became more hostile, the water bodies mostly disappeared,” he said.
“We don’t understand the mechanisms of how life originates. It’s extremely difficult to say whether it can originate there. We don’t know how the chemistry transforms itself into biology. That’s the big unknown of our age.”
Dr Atri, a research scientist in NYUAD's Centre for Space Science, has published his ideas in the journal Scientific Reports.
His paper was released after the launch earlier this month of the UAE’s Mars orbiter, which is scheduled to reach the Red Planet early next year before carrying out observations on the atmosphere.
Dr Atri’s hopes of testing out his ideas are pinned, however, on the forthcoming mission of the Rosalind Franklin Mars rover.
Produced by the European Space Agency and Russia’s Roscosmos State Corporation, this six-wheeled vehicle is expected to be sent into space in 2022 and to reach Mars the following year.
It will drill down below the surface of Mars, potentially uncovering micro-organisms living underground.
"This is super exciting. This is a new idea, it's never been tested, it can't be tested on Earth because such conditions can't be found here," said Dr Atri.
"It's literally alien life. There's a possibility, there's a likelihood. We've seen in very dry deserts, the Atacama [in Chile] and other places you have organic life."
The presence of life in Earth’s deep biosphere – an area extending many kilometres below the sea and land surfaces – has led other researchers in recent decades to suggest that there might be life below the surface of Mars.
Dr Atri said what distinguished his ideas was the significance of cosmic galactic radiation in powering the metabolism of the microorganisms.