Elon Musk says SpaceX has shifted its near-term priorities from Mars settlement plans to building what he called a “self-growing city on the Moon,” arguing the lunar target is faster and more achievable. In a post on X, Musk claims the company could complete this in less than 10 years, while doing the same on Mars would take over 20 years.

This marks a major shift for the aerospace company, as Musk points out that the logistics of first completing a proof of concept on the moon are easier with respect to launch windows and proximity to Earth. The SpaceX founder is notorious for promising optimistic timelines that never come to pass, and said in 2017 that a base on Mars would be ready for its first settlers as early as 2024.

In subsequent replies to other posts Musk predicted “Mars will start in 5 or 6 years, so will be done parallel with the Moon, but the Moon will be the initial focus.” He also said a manned Mars flight might happen in 2031.

Early last year Musk said in a post on X that SpaceX would be going “straight to Mars” and that “the Moon is a distraction.” This was in response to Space industry analyst Peter Hague pointing out that among other considerations, lunar regolith, a material found on the surface of the moon, is about 45 percent oxygen. In 2023 NASA proved this oxygen could be extracted, which would yield enormous payload savings as opposed to shipping liquid oxygen between Earth and Mars.

NASA’s Artemis missions, which SpaceX is a contractor for at certain stages, are planned to see humans back on the lunar surface by 2028. Artemis II, during which astronauts will circle the moon before returning to Earth, is set to launch in March of this year.

This article originally appeared on Engadget at https://www.engadget.com/science/space/spacex-is-pivoting-to-focus-on-a-moon-base-before-mars-141851264.html?src=rss