New research suggests that alien life on Mars may have been possible at some point in the planet's history. However, it may not be what one would normally think when the word "Martians" is mentioned, and such life may have existed billions of years ago, according to new findings from NASA's MAVEN Spacecraft.
For years, many have theorized that it may be possible for Mars to host some form of life, or that the planet may have hosted life at some point in its past. And while some of these theories can head into the realms of science fiction, such as the possibility of a nuclear war that destroyed the Martian atmosphere, other theories have more basis in science. Earlier this week, the Daily Express wrote that an asteroid strike may have caused a mega-tsunami that would have resulted in a massive extinction event after it engulfed Mars in water.
The study in question came short of suggesting there may have been alien life on Mars, but new research from NASA based on findings from its MAVEN Spacecraft does hint at this.
In NASA's official press release, the space agency explained that there may have been some forms of microbial life on Mars when it was still a young planet. But since our sun was still at a similarly young age, its ultraviolet radiation and solar winds were far more intense, thus resulting in much greater atmospheric loss on the Red Planet at this early stage in its life.
"It's possible microbial life could have existed at the surface early in Mars' history. As the planet cooled off and dried up, any life could have been driven underground or forced into rare surface oases."
Liquid water is considered to be one of the key features that would allow life to be hosted on a planet. But at the present, it isn't stable on the Martian surface due to its cold and thin atmosphere. But there are other features on Mars, such as dry riverbeds and certain minerals, that suggest that the planet once had liquid water, and may have had a climate warm enough to allow that water to flow.
MAVEN principal investigator Bruce Jakosky and his colleagues analyzed how much of two argon gas isotopes were present in the Martian atmosphere and on the planet's surface and attempted to see how much of this noble gas was lost in space over billions of years. The NASA press release pointed out how the lighter of the two isotopes tends to float off into space faster, leaving whatever is left behind mixed in with the heavier isotope.
As noble gases such as argon cannot be trapped in rocks, they can only be removed by the "sputtering" phenomenon, where ions caught in solar winds can bounce atmospheric gas into space due to their high speeds. The researchers measured how much argon may have been lost by sputtering, then did the same to some other atoms and molecules, primarily carbon dioxide.