Spacecraft Oxygen: How Astronauts Breathe in Zero Gravity

In space, where there's no air, astronauts need oxygen to breathe.

Spacecraft use special systems to make oxygen.

They split water into oxygen and hydrogen.

The ISS has systems to do this.

Astronauts also have backup oxygen tanks.

During spacewalks, they use portable oxygen supplies in their suits.

Scientists are working on new ways to recycle air, which will be important for future trips, like to Mars.