While companies like SpaceX are working how we get to Mars, NASA has already started investigating the possibility of what a home would look like once we actually got there.

In 2015 it launched the 3D-Printed Habitat Challenge where it invited teams from all over the world to enter designs for a habitat that could comfortably survive Mars’ cruel conditions.

Now some three years later NASA and Illinois’ Bradley University have chosen their finalists.

Each of the Martian homes had to be evaluated using specialised software that determined whether or not each of them could realistically survive the extreme weather that can be found on the red planet. That meant checking radiation shielding, structural integrity as well as backup systems in case the lights went out.

The next step for each of the teams will be to actually build some mockups of their habitats so that NASA can pick one that it feels could actually be the first home on Mars.

Here are the five winners:

1st Place: Team Zopherus of Rogers, Arkansas

This remarkable design envisages a lander arriving before humans. The lander then attaches itself to the floor and inside it contains everything you need to 3D print a building. Once it’s built the lander lifts itself back off and starts the process all over again until you have an entire base built ready for human arrival.

2nd Place: Team AI. SpaceFactory of New York 

This second place entry is called ‘Marsha’ and sees astronauts living in large 3D printed towers. The team felt that a large tower was more structurally secure than the conventional domes that we so often see. Unlike most buildings, this one actually expands and contracts, adapting to the vastly changing Martian weather.

3rd Place: Team Kahn-Yates of Jackson, Mississippi

This slightly more alien-looking design is thanks to the huge dust storms that can ravage the planet’s surface. Team Kahn-Yates came up with the rather clever idea that the main landing craft would also double as the inside of the house. Once it had settled, 3D printing arms would then cocoon the habitat with the foundation and the outer walls. Inside would be a large, airy space where plants could grow alongside the main living space.

4th Place: Team SEArch+/Apis Cor of New York

Arguably the most distinctive-looking of all the designs. Team SEArch have created an architecturally attractive building that’s designed around protecting its inhabitants from the increased radiation exposure that takes place on Mars’ surface. Huge 3D printed shells overlap each other and protect two inflatable habitats that have been sunken slightly into the ground. This design protects against the worst radiation while still allowing light in.

5th Place: Team Northwestern University of Evanston, Illinois

Northwestern University have perhaps the most conventional design here, opting for a standard 3D printed dome. Firstly, a robot inflates the initial human habitat, the 3D printing robots then create the shell over the top of it, assuring a secure fit. The inside is split up between ‘wet’ and ‘dry’ rooms which keeps things nice and separate for those who will have to spend a year or so living there.