Life on Mars not strong enough to invade us
NASA's Mars Curiosity rover has made some startling discoveries.
The Red Planet may have the building blocks of life,... suggesting it was once inhabited... or perhaps still is.
Ro Aram has the full story.
NASA has revealed that the Curiosity rover found an array of organic molecules on the surface of Mars.
These are the carbon-based compounds that make up life as we know it.
Hints of organic molecules have been found before, but NASA scientists say the latest discovery provides the strongest evidence to date of possible life on Mars
However, researchers did note they could have come from somewhere else.
"Now there are three different sources organic materials too. One of them is the biology. One of them could be meteorites that are in falling into the surface and being directly deposited. And the other one is a rock forming processes that might generate organic matter all on their own and they might be the ones that are being brought in by rivers. We don't have enough information from the observations we've made to tell what the source is and how it got in there."
In addition to the carbon-based molecules, Curiosity also found methane in the Martian atmosphere.
The gas is usually emitted from biological sources and only survives for a few hundred years at a time.
Methane can be produced through geological or chemical reactions, but its sharp seasonal increases make a stronger case for possible present-day life.
"So today we're announcing a discovery of a repeatable identifiable seasonal pattern in the methane measurements. And we can look here at the graphic and we can see that it's in that in the lower background level because most of the time I'm not looking at spikes and we see this low background level. You can see from the winter to the summer this growth, and the big surprise to is not only have we got this wonderful repeatability but the seasonal cycle changes by a factor of three. That's a huge change."
The latest discoveries have provided a good stepping stone for future missions to visit and analyze locations on Mars with more detail, bringing us one step closer to answering science's most pressing question - are we alone in the universe?