Researchers analyzed Martian materials collected by the Curiosity rover, which led them to believe that evidence of Martian life may have been wiped from existence.
Background: Was There Life on Mars?
The search for extraterrestrial life has been of significant interest since the 19th century, and Mars has been a primary focus of such endeavors. While hearing the phrase “life on Mars” may create images of science fiction-esque advanced and intelligent aliens in one’s mind, it is more likely that life existed in the form of microorganisms instead. The red planet is often portrayed as an extremely inhospitable and barren wasteland. While it is true that conventional and complex life as we know it would have a rough time surviving on it today, recent discoveries have indicated that Mars could have once supported life. It was discovered that underneath the Martian surface lay massive deposits of ice and salt lake reservoirs. Being that water is a crucial ingredient for the survival of life as we know it, the discovery was huge when it came to the question of whether or not there exists life on Mars. The Curiosity rover, launched by NASA in late 2011, has patrolled Mars’ Gale Crater- hypothesized to be a dried-up lake for over nine years, and has been studying Martian geology to learn more about the red planet as well as its capabilities for sustaining life.
Analysis: What did Curiosity Discover?
Unfortunately for the quest for Martian life, a new discovery by the Curiosity rover has shown that proof of life found in Mars’ geology may have been wiped clean by extremely salty brine water. NASA’s rover made the discovery while investigating the presence of clay in the Gale Crater, clay being primarily created by water- a key sign of life- eroding other rocks. Curiosity obtained samples by drilling into the Martian surface, samples that researchers would then discover contained only half of the presumed clay content inside.
They believe that brine water had found its way into the clay-rich rock and removed much of it, potentially erasing biological evidence of life, given clay’s remarkable ability to maintain fossilized remains. Since Mars contains no tectonic plates, scientists thought that the clay layers in the Gale Crater would likely remain similar to how they were billions of years ago. Instead, the brine shifted the minerals around.
Despite what would seem to be a significant setback in pursuit of life on Mars, researchers continue to remain optimistic and overall are positive about the discovery. They found that despite original indicators of life being swept away, it has created the necessary conditions to support life below the Martian surface in its wake through a process known as diagenesis. It shows that not all Martian soil in the crater is fit for finding signs of life, but the parts that do the job well are at least extremely close. The Perseverance rover, which landed on the red planet in February of this year, will be working alongside Curiosity to collect proper samples to potentially send back to Earth.
Outlook: The Future of the Curiosity Mission
It is hard and would be irresponsible to say that we are just on the cusp of finding life on Mars because, in reality, it is still unclear whether it has ever existed or not. However, more and more known essential survival conditions have been found over the half-decade that has passed since initially discovering evidence of Martian water.
According to Curiosity, one comes in the form of a potential leak of methane gas emanating from the surface, which could mean the existence of microbial life. With these discoveries, it can be said that the search for life is getting continuously narrower in its focus, and the odds of it being successful are increasing. There are many exotic and extreme environments on Earth where life prevails, making it not entirely out of the realm of possibility that it exists currently on the red planet- or at least did at some point in time.
Should the Perseverance rover successfully return to Earth with its precious cargo of Martian samples intact, it may bring with it the answer to whether or not we are truly alone in the universe.
Liam Stewart is a junior at NYU studying Journalism and Political Science. He is currently covering Science, Space, and Technology at The Debrief. Follow him on Twitter: @stewwashere