Full spoilers follow for Avenger: Endgame, so jump on the Benatar and get out of here if you haven’t seen the movie yet!
Early on in Avengers: Endgame, Tony Stark and Nebula are lost in space, adrift on the Benatar. As the only survivors (not including Thanos) of the battle on Titan in Infinity War, they have managed to make it off that world in an attempt to get back to Earth. But with no fuel, no food, no water, and soon, no air, things are looking dire. Tony Stark records a message for Pepper Potts via his Iron Man helmet, but he doesn’t even know if she can receive it because, you know, outer space. And then, just when all hope seems lost and Tony appears to be almost dead, Captain Marvel shows up and flies them home!
Source: IGN.com One Big Question We Have After Endgame