Nasa scientist claims evidence of life on Mars

Inhospitable terrain: The average temperature on Mars is minus 63C. It can drop to minus 153C. © NASA

Has there been a cover-up? In a new article, a leading scientist claims that US space probes discovered life on Mars over 40 years ago but Nasa has always denied their full significance.

Watching video footage sent from a probe on Mars, scientists were surprised to see ghostly lights moving across the planet’s surface.

They bore a strong resemblance to will-o’-the-wisps — the small fires sometimes seen on marshes, caused by the spontaneous ignition of methane. And since methane is produced by living organisms, the scientists had to wonder: had they found life on the Red Planet?

One of them, Gilbert V. Levin, is convinced that they had — but that Nasa chose to ignore the evidence. Now, he has published an article in Scientific American explaining his theory — and it has caused a fierce debate in space circles.

The Viking mission, on which two identical probes collected soil samples from different parts of the planet, included an experiment overseen by Levin called Labeled Release (LR).

He describes it as “a very simple and fail-proof indicator of living micro-organisms”. It involved injecting nutrients into the soil to see whether CO2 gas was given off. If it was, it would suggest that the nutrients had reacted with micro-organisms.

“On July 30, 1976, the LR returned its initial results from Mars,” Levin writes. “Amazingly, they were positive […]. It seemed we had answered that ultimate question.”

Nasa, though, didn’t support Levin’s conclusion. None of its experiments, it said, had found any actual organic matter, so the LR’s results must have been caused by a reaction with a substance that wasn’t alive.

But, as Levin points out, no experiment in the 43 years since has shown what that substance might be.

Furthermore, he argues, Viking and later probes have provided other indications of life. These include the will-o’-the-wisp footage, traces of surface water, and dark patches on rocks which – when their colour was analysed by Viking’s imaging system – appeared identical to lichen.

Now that Nasa is planning to send astronauts to Mars, Levin believes that it’s more important than ever to establish the truth. “Any life there might threaten them,” he says, “and us upon their return.”

Has there been a cover-up?

Cosmic conspiracy?

It’s quite possible, say some. Nasa wouldn’t have put Levin in charge of the experiment unless they considered him the best man for the job, so it’s bizarre that they should choose to ignore his conclusions. Moreover, with the world’s most powerful nations vying for scientific supremacy, the USA might well want to keep its knowledge of alien life secret until it has explored every last detail and worked out how best to exploit it.

Others point out that none of the probes after Viking carried out a similar experiment, which they surely would have done if Nasa had felt any confidence at all in Levin’s findings. It’s inconceivable, too, that any country — or scientist — making the most important and prestigious discovery in history could resist telling the rest of the world for four decades.

You Decide

  1. Do you think Nasa might deliberately cover up evidence of alien life?
  2. Is it a good idea to look for life on other planets?


  1. Make a poster showing Mars with its surrounding planets, and giving the distances between them.
  2. Imagine you are sending a probe to another planet. List the five most important experiments you think it should carry out.

Some People Say...

“I don’t think the human race will survive the next thousand years, unless we spread into space.”

Stephen Hawking (1942-2018), physicist and cosmologist

What do you think?

Q & A

What do we know?
Gilbert V. Levin designed an experiment which he believed would show whether there was life on Mars, and the results convinced him that the answer was yes. Viking and three other probes found enough surface water to sustain micro-organisms. In a more recent experiment, micro-organisms from Earth have survived outside the International Space Station, showing that it is possible for life to exist even in the most extreme conditions.
What do we not know?
How Nasa decides what information should or shouldn’t be made public. In order to receive funding for its programmes, it needs to convince the US government — and voters — that it is making discoveries which are of real benefit to the nation. This is all the more important now that it faces competition from private projects, such as Elon Musk’s SpaceX. But it may want to keep some of those discoveries secret from other space powers, particularly Russia and China.

Word Watch

A colourless gas.
Life forms too small to be seen without a microscope.
The scientific formula for carbon dioxide.
A plant which is a combination of fungus and algae, usually found on rocks and trees.
Impossible to imagine.
Deserving respect.


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