Evidence of Martian Aliens: Ancient Microbial Life
- Science Holic
- Nov 11
- 3 min read
Author: Jeffrey Chen
Editor: Kacey Ye
Artist: Felicia Chen
Due to the extreme weather conditions and lack of an ozone layer that allows for unhindered ultraviolet radiation, there is likely no life present on Mars today. However, signs of life on ancient Mars have been present since 1996, beginning with the discovery of evidence for microscopic life from a meteorite belonging to Mars. Over the course of the past few decades, further findings have been made to suggest that ancient Mars was likely able to have conditions to support life.
For example, Mars lies within the Goldilocks zone, evidence of a large underground water reservoir, and the detection of methane in Mars’ atmosphere. Another factor that makes the theory possible is the presence of extremophiles on Earth, which are able to survive both extreme heat (thermophiles) or extreme cold (psychrophiles)
The Perseverance Rover landed in February of 2021, with the goal of searching for signs of life to determine if it could be habitable for humans. Recently, the rover collected a sample found in an ancient riverbed of the Jezero crater, in a rock formation named Bright Angel. The rock that the sample was collected from, named Cheyava Falls, contained a mixture of compounds that could act as a source of energy for microorganisms, composed of carbon, sulfur, phosphorus, and rust. Furthermore, colorful spots were found on the rock, potentially byproducts of microbial life if they used carbon, sulfur, and sulfur as energy sources.
Another major discovery found within the rock sample was the presence of two minerals, vivianite and greigite, found in patterns on reaction fronts (area separating minor and significant reaction speeds). These minerals are important since vivianite is commonly found near decaying organic matter, and greigite is produced by some microorganisms. Although continuous high temperatures and acidic conditions are also able to produce these minerals abiotically, there is no evidence that these conditions affect the rocks of Bright Angel.
This finding also suggests that Mars was habitable for longer than it was theorized to be, since the biosignatures were also found within the youngest sedimentary rocks.
It is important to note that although abiotic factors do not seem to have caused the presence of the minerals, they should not be completely left out of the equation. Scientists must continue to eliminate variables that could’ve caused the formation of the minerals vivianite and greigite, ensuring to provide enough evidence to guarantee whether or not microbial life really existed on ancient Mars.
In addition to eliminating variables that could have formed vivianite and greigite abiotically, future missions have been planned out by NASA to continue this search for life on Mars. One of such missions is the Mars Sample Return (MSR) program, a joint mission between NASA and the European Space Agency, aiming to send Martian rocks, soil, and atmosphere to Earth in order to conduct detailed analysis. This mission will allow for greater certainty about findings made previously since the samples collected from Mars may be able to provide further evidence to support claims about ancient Martian life, geological and geochemical development, and the evolution of the atmosphere on Mars.
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