Forward-looking: NASA has shown off two spacesuits that astronauts will use to walk on the lunar surface. They're still in development, but the space agency says they'll be ready for its planned return to the moon in 2024.

Two engineers showed off the spacesuits, which will be used for the Project Artemis moon program, at NASA's Washington DC headquarters. The bulkier of the two suits, called the Exploration Extravehicular Mobility Unit (xEMU), will be worn on the moon's surface. It offers more flexibility than previous designs, allowing astronauts to reach overhead, across their bodies, and letting them twist at the waist - movements that previous suits couldn't perform.

In addition to fitting a wide range of astronaut sizes, the xEMU is designed to cope with the extreme environment of the moon's surface. It has no zippers or cables, and the components are sealed, keeping out the fine dust. It can also withstand temperatures between 250 and minus 250 degrees Fahrenheit.

"Basically, my job is to take a basketball, shape it like a human, keep them alive in a harsh environment, and give them the mobility to do their job," said NASA's lead spacesuit engineer Amy Ross .

The other suit is made of an orange fabric and is much thinner. Astronauts will wear them while traveling to and from the moon, and they'll be able to live inside the suits for days should a spacecraft experience sudden depressurization.

"This is the first suit we've designed in about 40 years," said Chris Hansen, a manager at NASA's spacesuit design office.

In addition to using the suits on the moon, NASA plans on adding modifications so they can eventually be used for future missions to Mars.