Finding signs of life on Mars has always been one of the missions of the rovers sent on the Red Planet's surface. Multiple observations from these rovers have helped scientists identify signatures of microbes, which signify that Earth is not the only planet on the Solar system that hosts life on the Solar System.
However, Mars has already fooled scientists before and until today, they have yet to fully explain all of the planetary workings of the Red Planet even as NASA's Curiosity rover observed mixtures of carbon isotopes.
Life on Mars: Evidence From NASA Curiosity Rover Remains Mysterious Until Martian Rock Sample Will Be Analyzed
Finding Signs of Martian Life in Rock Samples
Past observations of Mars showed that it was not a world awash easily in detectable life. In 1996, scientists recovered a Martian rock sample from the Allan Hills region of the Antarctic that appeared to contain microfossils in which tiny worm-shaped, mineralized signs of life are seen as evidence of life some 4.1 billion years ago.
Astrobiologist Kendra Lynch said that the findings fueled so much in the astrobiology field because they made scientists think about what humans know so far about life.
According to National Geographic, Mars exploration welcomed a new era in 2012 when NASA's Curiosity rover landed on the Red Planet's Gale Crater. The rover's primary goal is to search for signs of life and past habitability of the planet, such as water, organic compounds, and energy source.
Finding the lake was easy as the Curiosity rover immediately identified rocks that could only be formed when water was present. But the rest was not that so simple to detect. For many years, the rover continued its search and managed to find numerous organic molecules and spotted signs of ancient hydrothermal activity.
Furthermore, the Curiosity rover also detected methane gas in the Gale crater when seasons change. If this was on Earth, it would be a strong indication of beings with active metabolisms. However, none of these observations have been linked to biology.
Astrobiologist Christopher House from Pennsylvania State University said that most carbon-related processes on Earth are related to biology, but Mars is a different planet and should be treated differently.
ALSO READ: What Was Mars Like in the Past? Scientists Say Red Planet Was More Beautiful Than Earth Before
NASA's Curiosity Rover Finds Tantalizing Organic Compounds on Mars
Last month, NASA announced that the Curiosity rover has found "tantalizing" Red Planet organic compounds that could be a sign of ancient Martian life. But as Space.com reported, it would take a lot more to prove that hypothesis.
The rover has been collecting Martian rock samples for years. Some of the powdered rock samples they collected contain organics rich in isotopes of carbon that are also found on Earth, which is associated with life. But researchers said that it is still too early to conclude anything as many Martian processes remain mysterious.
Retired Curiosity's Sample Analysis at Mars (SAM) chemistry lab principal investigator Paul Mahaffy said in a statement that their team is finding interesting things on Mars, but more evidence is needed to say that they have finally identified life on the Martian surface. For now, they are looking for what could have caused the carbon signatures they detected on the rocks.
RELATED ARTICLE: False Fossils on Mars: Explorers Searching For Life on Red Planet Can Be Fooled, Research Says
Check out more news and information on Mars in Science Times.