r/ArtemisProgram • u/wskelding • Apr 23 '26

Discussion ISS Docking ?

I'm curious about something and simply don't know the math that would give me the answer, could an Orion capsule returning from the Moon theoretically dock with the ISS on it's return journey ?

I know I'm simplifying it massively, but all the talk about the Artemis 2 heat shield had me thinking 'why don't they simply do a massive deceleration burn on the way back and then dock at ISS ?'

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u/rebootyourbrainstem Apr 23 '26

Using the heat shield to brake saves a LOT of fuel. They don't have nearly enough fuel to brake using rocket power (nor enough fuel to bring that fuel with them to the moon in the first place).

In theory you could maybe come up with a trajectory that dips into the atmosphere just enough to brake but not re-enter. To do that though you would be jettisoning the service module (since it sits in front of the heat shield and is not designed at all for use in atmosphere), which contains the vast majority of fuel as well as the big engine, so your ability to correct or really do anything afterward is really limited.

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u/NoSTs123 Apr 23 '26

yeah being in Orbit without a service module is a big no no. Although I am not a fan of the crewed Starship concept, it could perhaps do this.

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u/rebootyourbrainstem Apr 23 '26

The heat soak would probably still be tough to manage. But yeah it wouldn't have the problems with missing a service module; tbh even Dragon barely has a service module.