NASA's mission to return samples from Mars and potentially discover the first signs of alien life has a new timeline. The samples may arrive sooner.

NASA has arrived at two ways of returning samples collected on Mars to Earth. Now, the agency will test the options to see if the cache can make it back in the 2030s.

The agency has collected 30 samples on the red planet but the cost of getting them back had delayed the Mars Sample Return mission. It was initially estimated at $11 billion, with a 2040 return date: a price tag and timeline that administrator Bill Nelson explained was “simply unacceptable.

The Mars Sample Return mission has been ranked as the highest priority by planetary scientists, who hope to find signs of ancient life on Mars.

NASA is pitching a cheaper and quicker way of getting rocks and soil back from Mars. Administrator Bill Nelson presented two options on Tuesday, less than two weeks before stepping down as NASA's chief.