Could there be life on Mars?
For over a century now, the question: “Is there life on Mars”, has presented us with songs, films, a TV series and volumes of scientific commentary. Wondering about life on another planet exemplifies human curiosity, and it’s in someway inconceivable to imagine we on Earth are the only ones out there. With the revelations surrounding the existence of water on Mars, perhaps there is also life.
It’s a scientific fact that no organism can survive on our planet without water, but we aren’t even close to understanding whether life can exist without water on Mars. Water may seem like a very common element to those of us here on Earth, and one that some of us perhaps take for granted. Deep down though, we are all aware of what an incredible asset it is. In addition to understanding how Mars has developed and changed over time, scientists are ever hopeful that finding water will help them find signs of life, either past or present.
A timeline of discovery
- In 1877 the Italian astronomer, Giovanni Schiaparelli, gave his description of the planet as being not unlike Earth with oceans and continents. The astronomer Percival Lowell further fuelled the imagination by announcing he had seen: “an irrigation system so linear and “trigonometric, that it could only be the work of a highly intelligent race.” Henceforth came the notion of Martians and the neverending search for the extraterrestrials from the red planet.
- It wasn’t until nearly a century later, in 1965, when NASA’s Mariner 4 spacecraft came within viewing distance of the planet’s northern hemisphere. This provided the first conclusive images of the planet which underwent close scientific scrutiny. The consensus was that Mars didn’t look like Earth – it looked like the moon, dry and arid.
- A few years later in 1971, Mariner 9 brought back contrary photographs of dry river beds and canyons which seemed evident of the existence of water on the Martian surface. This information fuelled much speculation and during the 90’s there were several expeditions to Mars to study the planet and analyse the surface minerals. The results were again in favour of there being at one time a body of salty water.
- In 2002, the Mars Global Surveyor spacecraft spotted features suggestive of liquid water on the surface of Mars which were not remnants of billions of years ago, but more recent. Although diminutive, the water supply seemed to emanate from canyons to form steep, dark gullies.
- In 2004, analysis made by NASA showed clearly that the material making up the rock had once been saturated with liquid. Further inspection into the layered Martian rock showed undeniably that water had once formed lakes, rivers and shallow seas.
From these conflicting facts, the search for water on Mars has grown into one of the world’s most continually riveting mysteries, until last September when NASA’s Science Mission announced that:
“Our quest on Mars has been to ‘follow the water,’ and now we have convincing science that validates what we’ve long suspected. We can confirm that water — albeit briny — is flowing today on the surface of Mars.”
So although we are still a long way off discovering whether or not Martians exist, we are one step closer – aren’t we?
[Photos by WikiImages]