For nearly four years, NASA's Perseverance rover has journeyed across an unexplored patch of land on Mars—once home to an ancient river delta—and collected a slew of rock samples sealed inside cigar-sized titanium tubes.
These tubes might contain tantalizing clues about past life on Mars, but NASA's ever-changing plans to bring them back to Earth are still unclear.
On Tuesday, NASA officials presented two options for retrieving and returning the samples gathered by the Perseverance rover. One alternative involves a conventional architecture reminiscent of past NASA Mars missions, relying on the "sky crane" landing system demonstrated on the agency's two most recent Mars rovers. The other option would be to outsource the lander to the space industry.