The race to find intelligent life, or any life at all, beyond Earth has been a heated space scramble for decades. Even though no concrete evidence of extraterrestrials has ever been confirmed, it seems like every space probe ever launched and scheduled to launch has a «FIND LIFE» stamped in its mission.
That isn’t to say we don’t have our theories for where life might be hiding. Here, we take a look at some places we’ve explored, and some we haven’t.
There have been around 22,000 documented meteorite discoveries on Earth and many have been found to hold organic compounds.
In 1996, a group of scientists announced they had spotted strong evidence of microfossils on a Martian meteorite found in Antarctica showing that life may have existed on the Red Planet some 3.6 billion years ago. After years of intense debate, the issue whether the Martian meteorite contains life or not remains unresolved.
If this were true, it would also give excellent evidence to support the theory of «panspermia.» Literally meaning «seeds everywhere,» panspermia is the idea that life came from outer space and planets exchanged life — «life» in this case meaning bacteria, which can be dormant and withstand harsh environments. Life could have existed on another planet, maybe even one as close as Mars, and then made its way to Earth instead of originating here.
The next frontier, Mars has long been a target for extraterrestrial life hunters, but its arid and barren landscape has turned our attention away from finding little green Martian men to finding simpler life forms.
But there is evidence that the Red Planet had a warmer and wetter past: dried-up river beds, polar ice caps, volcanoes and minerals that form in the presence of water have all been found. In 2008, the Phoenix Mars Lander sent back photos of ice chunks it had found after scooping up handfuls of soil, a huge discovery in the search for liquid water — a key ingredient for life. Another key ingredient for life was found the following year: NASA scientists detected methane in the Martian atmosphere, indicating that the planet is still alive.
Although no life has been confirmed on Mars, scientists are hopeful that it’s just hiding. Methane-producing microbes were some of the earliest life forms on Earth, so if the same exists for the Red Planet, chances are these bacteria are well below the surface.
This Jovian moon isn’t trying to give life the cold shoulder. In fact, it could be a home not just to simple micro-organisms, but also complex life.
Scientists have theorized for years that an ocean could be hiding beneath Europa’s icy surface, one that even contains oxygen. After studying how quickly Europa’s surface ice was replenished, University of Arizona researcher Richard Greenberg estimated in 2009 that enough oxygen reaches the subterranean ocean to sustain 6.6 billion pounds of «microfauna» — more complex animal-like organisms.
Before we get too carried away, it’s important to note that no definitive evidence has been found to support that said ocean even exists beneath the ice.
«A journey of a thousand miles must begin with a single step.» — Lao Tzu Copyright © Demetrios the Traveler