This could potentially be a ground breaking discovery.
Since David Bowie posed the question back in 1971, we've been fascinated with the question...'is there life on mars?'
Well that question could be one step closer to being answered! After a Nasa robot on Mars detected its largest amount of methane yet, which could be an early sign of life on the red planet.
Methane gas is associated with living things here on Earth, however it can also be created naturally.
Scientists say the Curiosity Rover isn't capable of figuring out where the methane has come from.
"With our current measurements, we have no way of telling if the methane source is biology or geology, or even ancient or modern," said SAM Principal Investigator Paul Mahaffy from Nasa's Goddard Spaceflight Center in Greenbelt, Maryland.
While Curiosity continues to measure some spikes, and one of these has been confirmed by the European Mars Express satellite in orbit at the planet - another spacecraft, supposedly with much better sensitivity, has seen nothing.
On Earth methane usually comes from wetlands, livestock, biomass and fossil-fuel burning, landfill and rice paddies.
When the source of the methane finding on Mars is discovered it could potentially be the moment we discover we aren't alone in the universe...
