Comment Re: The "Science" of Ad Adstra (Score 1) 89
There's a big difference in the Orion project ideas and the concept of just taking a normal ship (looks a bit like a capsule that might go to the moon), pointing it towards Earth, detonating a single nuke next to it, and having it fly all the way back to Earth from Neptune. Or from outside of the heliopause. The movie thinks those are the same thing for some reason.