NASA Rover Curiosity
This set of images compares rocks seen by NASA's Opportunity rover and Curiosity rover at two different parts of Mars. On the left is " Wopmay" rock, in Endurance Crater, Meridiani Planum, as studied by the Opportunity rover. On the right are the rocks of the "Sheepbed" unit in Yellowknife Bay, in Gale Crater, as seen by Curiosity. (credit: NASA/JPL-Caltech/Cornell/MSSS )

In a major breakthrough, NASA scientists announced on Tuesday that Mars could have supported microbial life billions of years ago.

Analysis studying the first Martian rock powder sample by Curiosity rover shows the presence of sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon - some of the important chemical ingredients that can provide energy source for life.

"A fundamental question for this mission is whether Mars could have supported a habitable environment," Michael Meyer, lead scientist for NASA's Mars Exploration Program at the agency's headquarters in Washington, said in a statement. "From what we know now, the answer is yes."

Last month, Curiosity rover drilled into a flat, veiny rock called "John Klein" in Gale Crater of the Red Planet, using a percussive drill mounted on its robotic arm. Gray rock powder samples were collected from the interior of the rock and a small portion was ingested into the rover's Chemistry and Mineralogy (CheMin) and Sample Analysis at Mars (SAM) instruments.

Based on the analysis carried out by CheMin and SAM, scientists have found that the rock is made up of a fine-grained mudstone containing clay minerals, sulfate minerals and other chemicals. The data obtained from the instruments indicate that the Yellowknife Bay area, which the rover is currently exploring, was the end of an ancient river system or an intermittently wet lake bed that could have provided chemical energy and other favorable conditions for microbes to thrive billions of years ago.

Earlier, NASA's other rovers - Spirit and Opportunity - have found wet environments on the Martian soil. Such areas were harshly oxidizing, acidic or salty - extreme conditions that would have been challenging for modern Earth-type organisms to survive.

However, data obtained from Curiosity rover reveals that the ancient stream bed that flowed in the Yellowknife Bay area during the formation of the rock could have supported microbial life that are commonly found on Earth.

NASA scientists found a mixture of oxidized, less-oxidized, and even non-oxidized chemicals that could have provided energy to live for Earth-like microbes. "The range of chemical ingredients we have identified in the sample is impressive, and it suggests pairings such as sulfates and sulfides that indicate a possible chemical energy source for micro-organisms," said Paul Mahaffy, principal investigator of the SAM suite of instruments at NASA's Goddard Space Flight Center in Greenbelt, Md.

However, scientists are yet to confirm if the organics detected were from the Martian rock or from contaminants brought from Earth. They also have to find out if the organics were formed as a result of chemical reactions when the rock was heated, reported The New York Times.

Researchers are further planning to use an additional drilled sample to help confirm these results.

Curiosity landed on the Gale Crater in August last year. The rover is on a two-year mission to find out if the Martian conditions could have ever supported microbial life.