It has just been two years since NASA's Curiosity rover landed on the red planet's Gale Crater but efforts to bring the spacecraft to explore the surface of Mars are apparently no longer in vain.

In just two years since the rover touched down on Mars in August 5, 2012, it has already provided crucial information about the red planet.  In its first year of operation, the spacecraft has already accomplished its major objective of determining if Mars has environmental conditions that could support microbial life.

In March last year, the team behind Curiosity rover announced that the powder  the rover drilled out from a Martian rock suggests that Mars may have been able to support microbial life billions of years ago. Scientists found that the powder contained sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon, which are known to be elemental life ingredients. They also found that the sample contained at least 20 percent clay minerals, which on Earth, are produced with the reaction of fresh water with igneous minerals.

Lisa May, the lead program executive for NASA's Mars exploration said that the car-sized, six-wheeled Curiosity rover has already met the success criteria of its mission but with billions of dollars spent on getting the spacecraft on the red planet, scientists plan to keep using it.

"Curiosity has already met its mission success criteria, but there's always the intention of continuing as long as our spacecraft lets us," May said. "We have spent $2.5 billion to send this spacecraft to Mars, and we'll use it to learn and explore as long as we can."

Besides providing evidence that ancient Mars could have supported life, the Curiosity rover also detected dangerous radiation levels on the red planet, a crucial information as NASA prepares for future manned mission on Mars. NASA scientists and engineers could use this information to develop technologies that could give astronauts ample protection from harmful radiation.

Scientists also said that the spacecraft's most important findings may yet be discovered. Curiosity is currently nearing Mount Sharp whose rocks are believed to provide the geological history of the red planet that spans billions of years.

"The hope is that we can traverse those rock layers and read Mars like a history book, going from the earliest time period where we see some evidence for clays from orbit, to sulfates, to this dusty layer on top where it might represent the modern conditions," Ashwin Vasavada, Curiosity's deputy project scientist, said.