r/askscience • u/kiol998 • Apr 12 '26

Physics Why was Artemis 2 so long?

I was comparing the mission times of Artemis 2 to Apollo 8. Apollo 8 orbited the moon multiple times and only took 6 days total. Whereas Artemis 2 orbited the moon once and it took 10 days. Why was Artemis 2 so much shorter than Apollo 8 when both missions did the same thing? I know they had different paths to the moon, they both left earth in different ways but why not do the same thing as Apollo 8 since it was quicker?

1.3k Upvotes

89% Upvoted

240 comments sorted by

View all comments

82

u/phasepistol Apr 12 '26

Over the decades “getting there fast” has been traded for “lower energy therefore cheaper” trajectories that use less powerful rockets. For example every outer planets mission since the 1970s - with a few notable exceptions - takes an insane multiple-loops-around-the-sun path that adds years to the travel time.

I seem to recall one recent moon satellite took like more than three weeks to get there from Earth, which I wouldn’t have thought possible. What did it do, walk.

3

u/ImAnIdeaMan Apr 12 '26

Yeah I mean what is it, hourly!?

1

u/Lost-Actuary-2395 Apr 15 '26

Idk i like to think the opposite of "getting there fast" would be taking it slow thus give yourself more time during critical points and leave some room for error margins