Yes, easily. Can you see any life in this image?
This is one of the most Mars like places on Earth, the hyper arid core of the Atacama desert A Tale of Two Deserts - Astrobiology Magazine
Yet there is life in this desert, lots of it, if you know where to look. Below the surface of the soil, just beneath the surface of rocks, in salt pillars etc.
It's not just hidden from sight. It's almost undetectable in such low concentrations. Curiosity and Viking could search this desert for decades and find nothing, if you don't know where to look.
But more sensitive rovers would be able to find the life here. ExoMars rover due to fly in 2020 has instruments that could find life here, as it was tested there. There are much more sensitive instruments that have never yet been flown, but could be which could find the life easily.
Used to be thought that life on Mars would change the atmosphere, but there are many ways you can have life on a planet and it has no effect on the atmosphere. Either in a habitat that's not connected to the surface at all - or else - that the life is in such low concentrations that it doesn't have any noticeable effect on the atmosphere.
For instance Mars has a small amount of oxygen in its atmosphere already - through non biological processes. If it had life producing oxygen, then you'd never notice the signal, not if the life was as rare and slow growing as it is in these remote dry deserts on Earth - and if the most habitable places on Mars are similar in habitability to these deserts.
It's probably mostly microbial if it exists, but it could also be multicellular life, e.g. lichens on Mars, we wouldn't see that from orbit either.
As for the icy moons, the oceans are hidden from view below a layer of kilometers of ice. There could be almost anything down there. We wouldn't know even if there was intelligent life there, if it was non technological. Not that that seems all that likely, but it just shows how little we know.
For more on this: Our Spacecraft Could Look Straight At an Extraterrestrial Microbe - And Not See a Thing!
Yet there is life in this desert, lots of it, if you know where to look. Below the surface of the soil, just beneath the surface of rocks, in salt pillars etc.
It's not just hidden from sight. It's almost undetectable in such low concentrations. Curiosity and Viking could search this desert for decades and find nothing, if you don't know where to look.
But more sensitive rovers would be able to find the life here. ExoMars rover due to fly in 2020 has instruments that could find life here, as it was tested there. There are much more sensitive instruments that have never yet been flown, but could be which could find the life easily.
Used to be thought that life on Mars would change the atmosphere, but there are many ways you can have life on a planet and it has no effect on the atmosphere. Either in a habitat that's not connected to the surface at all - or else - that the life is in such low concentrations that it doesn't have any noticeable effect on the atmosphere.
For instance Mars has a small amount of oxygen in its atmosphere already - through non biological processes. If it had life producing oxygen, then you'd never notice the signal, not if the life was as rare and slow growing as it is in these remote dry deserts on Earth - and if the most habitable places on Mars are similar in habitability to these deserts.
It's probably mostly microbial if it exists, but it could also be multicellular life, e.g. lichens on Mars, we wouldn't see that from orbit either.
As for the icy moons, the oceans are hidden from view below a layer of kilometers of ice. There could be almost anything down there. We wouldn't know even if there was intelligent life there, if it was non technological. Not that that seems all that likely, but it just shows how little we know.
For more on this: Our Spacecraft Could Look Straight At an Extraterrestrial Microbe - And Not See a Thing!
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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