NASA Astronaut Explains What GOTG 3 Got Wrong About Star-Lord Almost Dying In Space

The actual science of the scene featuring Star-Lord almost dying in space in Guardians of the Galaxy Vol. 3 is revealed by a real-life NASA astronaut. In the climactic scenes of James Gunn’s Marvel Cinematic Universe trilogy capper, Star-Lord launches himself from the High Evolutionary’s ship to Knowhere, but gets stuck in space, and is eventually saved by a redeemed Adam Warlock. Before he’s saved, though, it’s an emotional moment during the Guardians of the Galaxy 3 ending in which all the other characters watch on as Star-Lord slowly dies. But, like much in movies, it’s not quite scientifically accurate.

In an interview with Vanity Fair, retired NASA astronaut and engineer Chris Hadfield breaks down the accuracy of various movies, including Guardians of the Galaxy Vol. 3. Although Star-Lord’s future in the MCU is thoroughly in doubt while he’s dying in space, Hadfield explains that someone could survive in space for about 30 seconds.

Hadfield goes into detail about what would actually happen to a person stranded in space without a space suit, explaining they’d only be conscious for about 15 seconds, and after 90 seconds, they’d suffer irreparable damage to their body that would result in death. Read his full comments below.

Our best guess is that you can live outside of a spaceship without a space suit for 30 seconds really no problem. But beyond about a minute and a half, there’s gonna be stuff [that] happens to you that does permanent, irreversible and deathly damage. Ninety seconds and you’re a satellite.

Within about 15 seconds, all the oxygen that is in your blood will have now come through your lungs the other way, and you will have breathed it out. So in about 15 seconds, you have blood without enough oxygen in it, and when it gets up to your brain, you’ll go unconscious.

You can see his face swelling up—that’s real. If you popped your helmet off in space, sure your lungs would sort of collapse, but also your blood would fizz like opening a can of Coke. Release the pressure and suddenly there’s bubbles in your blood and in your cheeks and in all of your flesh. And you’re gonna swell up. Not as much as he’s swelling up here.

Suddenly he’s got frost on his face—it wouldn’t happen like that. There’s no water on your face. It’s not gonna instantaneously freeze. You got a lotta thermal mass, it’s like sticking a big roast in the freezer. It doesn’t instantaneously freeze, it takes a while. Most of the stuff that’s happening [is] inside your body, but it’s really hard to show that to the movie audience, so that’s why they sort of exaggerated what’s happening to his face.

I think it would’ve been better if this had happened to Groot. I think Groot would’ve just like flown out of that one ship and gone, “Groot!” And then been on board the other ship, and it wouldn’t have been any big deal.

How GOTG 3’s Star-Lord Scene Is More Accurate Than Guardians of the Galaxy

Guardians of the Galaxy Vol. 3 isn’t the first time Gunn included a scene where one of the characters slowly dies in space, as there was a similar scene in the first Guardians of the Galaxy movie. After Nebula destroys the pod Gamora was flying in near Knowhere, she’s left floating in space, but Star-Lord saves her by giving her his mask and calling Youndu and the Ravagers to get them. Both Gamora and Star-Lord survive, but not before a perilous few moments in space during which their skin freezes over. This is consistent with how Star-Lord’s near-death in Vol. 3 is depicted, but there’s one difference.

In Guardians of the Galaxy, Gamora and Star-Lord don’t appear to swell up the way he does in Vol. 3—at least, not to the same degree. It’s unclear why the depictions of what happens to a person left unprotected in space is changed from the first movie to the third, but based on Hadfield’s explanation, it makes the third movie more scientifically accurate. Of course, it’s not entirely accurate, as Hadfield said, but adding the detail of Star-Lord’s face swelling gives it a bit more realism, and also ups the emotional impact of the scene in Guardians of the Galaxy Vol. 3.