No matter its goal, these work as "chemical clues" for researchers about Mars. After all, these are just organic molecules on their own, so we're still in the stage of chemistry, rather than biology. But it has found the ingredients for life on Mars.
Experts have hailed the two new studies as milestones for astrobiology.
The revelations build on a similar announcement made by NASA in 2014, where scientists confirmed that they had discovered chlorinated molecules on the planet for the first time.
"Organic molecules serve as the building blocks of life while most of the methane in Earth's atmospheric comes from animal and plant life, scientists explained".
The more we learn about Mars, the more it seems that the red planet once could have harbored life.
What has NASA found on Mars? The Viking Project was the first United States mission to safely land spacecraft on the Martian surface, as well as send back images. Using its drill, Curiosity takes samples of Mars and analyzes them in its onboard laboratory, sending the results back to NASA for further examination.
The samples were drilled from the base of Mount Sharp, inside a basin called Gale Crater that is believed to have held an ancient Martian lake. It likely held a lake, and now includes a mountain.
The fluctuations in methane were observed over three Mars years (roughly six Earth years) by Curiosity's Sample Analysis at Mars (SAM) instruments.
Q: What organic molecules did you find, and how do they compare with anything that is found or produced on Earth? Drilling beneath the surface, rather than sampling what was on top like Viking did, also helped. And, she says, it gives us an idea where to look. Over the intervening years, fluid flowing thought it would have initiated chemical reactions that could have destroyed the organic matter - the material discovered may in fact be fragments from bigger molecules.
"What the organic detections in the rock do is to add to the story of habitability".
Seasonal changes in methane at Gale Crater. With five years of data from a single location, they now have answers.
A potential explanation for the seasonal Martian methane. This is different from previous measurements of methane on Mars, which could not be repeated. Perhaps, some researchers speculated, Mars's remaining organics-and thus any signs of past or present life-were locked away in its subsurface depths. By exploring Gale Crater it has shown clear evidence that Mars once had liquid water on its surface, and views of the red planet from orbiting spacecraft have charted a desert landscape that appears to have been swept and hewn into shape by powerful flows of water. Then, the conditions would have been comparable to Earth.
The search for life on Mars over the past half century has been an exercise in lowering the bar combined with ever more sophisticated ways of seeking clues.
NASA's InSight Lander, launched on May 5, will land on Mars on November 26.
"That would be exciting because if that is done within two years, NASA can send a mission specifically to that place", he said.
Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters, praised the findings and said he is positive NASA's search for alien life is headed in the right direction.