NASA has set its sights on building homes on Mars. The US space agency has selected five winners of the latest phase of its “3D-Printed Habitat Challenge” to design 3D printed houses for the arrival of astronauts on the red planet.

18 teams were tasked with designing a virtual model of a 3D-printed house on Mars. They were encouraged to use recycled material and “indigenous resources” (basically Martian rocks) in an effort to keep the planet waste free. Each of the five winners won around $20,000.

The idea is to send a robot to Mars to autonomously print a habitat for the arrival of astronauts. The winning designs include a garden for food and oxygen, a roof that bends in case of “marsquakes” and a spherical house with a recreational room on the top floor.

When asked when she thought we’d see 3D-printed houses on other planets, Monsi Roman, NASA’s Centennial Challenges Project Manager, said “realistically, somewhere around late 2030.” She noted that we will probably first see one of these houses on the moon.

NASA hopes the competition will advance 3D printing technology in the construction sector on earth. The next phase of the contest is now focused on building the actual robot that will autonomously print part of the design. The final winner that makes it through the last round wins $2 million in prize money.