Tim Peake, a British astronaut on the International Space Station, is about to undertake an unusual driving test: guiding a Mars rover around obstacles in a dark cave while he's 249 miles above it in space.
The experiment is streaming live on the website of Airbus Defence and Space, which is headquartered in the UK. Peake is supposed to start around 10:20 am Eastern time, pending any last-minute changes.
The rover, developed by British scientists, isn't actually on Mars today — it's exploring the Mars Yard in Stevenage, about 30 miles north of London. The yard is a room filled with sand and designed to mimic the landscape of Mars.
Here's the obstacle course the rover, named Bridget, will have to navigate:
Transmitting signals from Earth to the moon or Mars can be slow — it takes seven minutes for a signal to travel to Mars, plus seven more minutes to make sure the signal went through. Controlling a rover from space is one way of cutting down on those delays.
The experiment is also meant to test how humans and robots work together: Peake will have to figure out a route for the rover himself, making adjustments along the way. That's important because it's easier for humans to figure out and respond to the tricky terrain. A misstep could leave an expensive robot stuck on another planet forever.
This video from Airbus explains the experiment in a bit more detail:
Airbus says Peake and Bridget's mission may also ultimately help astronauts prepare for future missions to the moon, perhaps even establishing a permanent base there, and to Mars.