A mission that could bring chunks of rock samples collected by NASA's 2020 Mars rover back to Earth for analysis could launch as early as 2022, scientists say.
NASA's Ames Research Center has developed a draft proposal for the "Red Dragon" project which would see NASA team up with Elon Musk's company SpaceX.
The mission, which remains a concept at the moment and not an approved mission, would send Mars rock samples back toward Earth, where researchers could examine the material for possible signs of past life on the red planet.
The sample-return project would use SpaceX's Falcon Heavy rocket and a modified version of the company's robotic Dragon cargo capsule, the concept's developers said.
Red Dragon is "technically feasible with the use of these emerging commercial technologies, coupled with technologies that already exist," said Andy Gonzales, of NASA's Ames Research Centre, during a presentation with the space agency's Future In-Space Operations (FISO) working group.
Mars is a cold and dry place today, but evidence gathered by NASA's Mars rover Curiosity and other spacecraft suggests that the planet was warmer and wetter, with lots of surface water, billions of years ago.
NASA aims to grab and cache samples from a potentially habitable environment with its next Mars rover, which is scheduled to launch in 2020. But the space agency does not yet have a firm plan or timeline for bringing this material back to Earth.
That is where Red Dragon could come in, Gonzales and his team said.
The researchers have drawn up a plan that uses a modified version of SpaceX's uncrewed Dragon cargo capsule, which has already flown six resupply missions to the International Space Station for NASA.
The Red Dragon variant would include a robotic arm, extra fuel tanks and a central tube that houses a rocket-powered Mars Ascent Vehicle (MAV) and an Earth Return Vehicle (ERV).
Red Dragon would launch toward Mars atop SpaceX's huge Falcon Heavy rocket, which is scheduled to fly for the first time next year.
After a long deep-space journey, the capsule would touch down near the 2020 Mars rover.
Red Dragon's robotic arm would then grab a sample from the rover's onboard cache and transfer it to a secure containment vessel aboard the ERV, which sits atop the MAV.
Red Dragon can also simply scoop up some material from the ground using its arm.
The MAV would then blast off from the centre of the capsule sending the ERV on its way back to Earth. The ERV would settle into orbit around our planet; its sample capsule would then be transferred to, and brought down to Earth by, a separate spacecraft - perhaps another Dragon capsule.
The ERV, meanwhile, would be placed in a sun-circling orbit so it could not contaminate Earth or the Moon with stray Mars material.
