Here’s a quick one from the Twitter-feed:
It is in fact true that Curiosity will soon be using her SAM (Sample Analysis at Mars) to effectively ‘smell’ the atmosphere of Mars, in what will be the first such analysis since Viking in the 70’s. The hope, I think, is to look for some methane – which has been detected from orbit. Methane could be indicative of some kind of biology – but we’ll wait on that for now and get back to the smell.
What does Mars smell like? That’s a good question – and not one we have a very easy answer to.
So here’s the thing, nothing we’ve ever sent to Mars has ever come back – so we don’t know for certain what anything on Mars smells like, but we can make a fairly good educated guess, and it runs like this…
The atmosphere on Mars is overwhelmingly made of Carbon Dioxide, so imagine the scent of a freshly opened can of soda water – the whiff of the gas, which is basically odourless, but has elements of sparkling freshness – a tingling… a hint of something. If you’ve access to such a can, I suggest you try it.
But – that’s not all, not by far, because Mars is dusty and rocky and that dust and those rocks are made of hematite along with a rusty material made of tholeiitic basalts (silica and iron based igneous rocks) as well. You will be familiar with the scent of rust if you’ve tasted blood – that stale metallic scent in your nose, like an old penny – and hematite is kind of salty, so that’s there too.
So Mars – as best as I can tell – smells like a carbonated can of salty blood. But only faintly so.
I suppose we’ll find out the real answer when Curiosity reports back to us in a week or so.