Private spaceflight firm Space Exploration Technologies, SpaceX, which is preparing to send a space capsule to the International Space Station this November, will team up with NASA to send a mission to search for life on Mars.

The "Dragon" space capsule of SpaceX will fly the NASA hardware to the red planet sometime around 2018, a NASA scientist has said.

The Dragon capsule is part of SpaceX's project to offer space taxi service with NASA funding. The primary mission will be to ferry cargo and astronauts to and from the International Space Station.

The Mars mission, which is more than half a decade away, has not been given an official name -- but one NASA astrobiologist has called it the "Red Dragon," according to space.com.

"I just want a cheap delivery system to go to Mars ... I don't care how it gets there," Chris McKay, of NASA's Ames Research Center, was quoted as saying.

Red Dragon is not NASA's next Mars mission, however. That will be a rover called Curiosity, whose mission will be to ascertain if Mars is capable of supporting life. However, the Red Dragon mission will be tasked with finding out if there is life on Mars.

The Viking lander NASA launched in 1976 had been unable to return any hard organic evidence of life on Mars.

Perhaps the biggest breakthrough in the search for life forms on Mars came in 1996, when scientists famously said "We are not alone." The basis for this proclamation was the discovery of evidence of fossilized microbial life in a meteorite from Mars. However, further analyses and research were inconclusive.

In March this year, NASA's Richard Hoover said in a paper that fossil evidence suggested the existence of cyanobacteria in carbonaceous meteorites from outer space.

NASA has proclaimed the next two decades are going to be important in its search for life on Mars. The first leg of a series of NASA missions will focus on establishing if Mars has ever been, and still is, an inhabitable planet.

"On Mars, we will therefore search for evidence of life in areas where liquid water was once stable, and below the surface where it still might exist today," NASA said.

NASA is planning a $2.5-billion Mars Science Laboratory (MSL), which will land on the red planet in Aug. 2012. While NASA hopes to send a man to Mars in about 25 years, SpaceX has more ambitious plans and says it could put a man in space in 10 or 20 years.

SpaceX's heavy-lift rocket, the Falcon Heavy, is expected to be launch ready in late 2012 or early 2013. This will carry the Dragon capsule to the International Space Station.

SpaceX CEO Elon Musk says Dragon has the potential to expand space exploration into the other worlds as well. "This would possibly be several tons of payload — actually, a single Dragon mission could land with more payload than has been delivered to Mars cumulatively in history," he told MSNBC.

And reducing the cost of commercial space exploration is a priority for him. "I want the commercial space sector to drive costs down," he said.