Listen to part of a lecture in an astronomy class.
There's been a lot of talk recently about life on Mars, at the level of microorganisms anyway, mainly because of a few important discoveries and inventions.
For example, one major discovery was that at one point water was present on Mars.
How do we know?
Well, in 2004, an exploration robot discovered jarosite there.
Jarosite is a yellowish brown mineral with a crystalline structure that's also found on Earth.
It contains iron, potassium and hydroxide.
The interesting thing is that on Earth at least it needs highly acidic water to form.
So we've got water or had it at one point.
And since most planetary scientists believe that water is essential to life, the presence of jarosite means that one prerequisite for life was once present on Mars.
But there's another thing about jarosite.
One step in its formation on Earth involves microorganisms; they actually speed up the formation of jarosite dramatically.
Now, theoretically it is possible for jarosite to form without the help of biological life forms.
But we don't really know for sure if this happens 'cause… well, because every corner of Earth has some form of biological life.
But jarosite on Earth incorporates all kinds of microorganisms into its crystalline structure.
So it's possible that if the jarosite on Mars was also formed with the help of microorganisms, we might be able to detect remnants of them in the samples we find.
And we have instruments now that will enable us to try to do this.
For example, there's a new instrument called the micro-fabricated organic analyzer, or M.O.A.
The organic analyzer is an amazing tool.
It will be able to collect soil samples and analyze them right there on Mars, pure, untouched samples.
It will let us eliminate the risk we would take of contaminating the samples if they were brought back to Earth.