Earth prepares a Martian armada

For decades when mankind peered at the red planet, he wondered whether an alien race might be peering back at Earth. Back then the question wasn’t whether or not life was there, but whether or not it was plotting the Earth’s destruction (Illudium Q-36 Explosive Space Modulator anyone?).

Today, we know that Martian life – if it exists at all – is going to be a little single cell and not a little green man. Although this eliminates the worry that a Martian race (fleeing their dying world) will launch an armada hell-bent on our destruction, it does make finding life on Mars a good deal harder.

Past efforts have drawn a bit of a blank but in the next few years planet Earth will be launching its own armada to the red planet and it is hell-bent on finding life.

Martian life, if it exists at all, is likely to be on the scale of bacteria so, rather than looking for the life itself, the coming missions will be looking for the faint and ephemeral chemical signatures that life leaves behind.

Above: Today, Mars’ surface is a frozen wasteland, but there is evidence that water once flowed across it’s surface. Ancient lakes and dry river beds tell of an ancient past that was once warm, wet and favourable for life.

If life emerged and evolved on early Mars then it is likely that its physical or chemical signatures are preserved in the planet’s rock record.

Above: Set for launch later this year, Nasa’s next generation rover, Curiosity, will be armed with experiments designed to search for those signatures.

Below: Evidence of life can also be found in a planet’s atmosphere. Biological processes produce gases, such as methane, as a by-product. Does the recent discovery of localised patches of methane in the Martian atmosphere indicate the presence of life?

Below: Even though the planet’s surface is scourged by deadly levels of radiation, it can only penetrate a few meters deep. Perhaps some of that ancient life survives today – protected from the harsh surface deep underground? But to find that, you need a to be able to drill beneath the Martian surface. This where ExoMars comes in – click the graphic to enlarge

On a separate note... does anyone else think that Mars rovers are starting to look an awful lot like 'Johnny 5' from the 1980's movie, Short Circuit?