this post was submitted on 21 Apr 2025
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SpaceflightMemes

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[–] [email protected] 20 points 1 week ago (10 children)

People shit on NASA all the time, as if "private space exploration" is the future, but I did the math on their JUNO mission and their margin of error was 1%.

NASA is goated.

[–] [email protected] 4 points 1 week ago (3 children)
[–] [email protected] 10 points 1 week ago* (last edited 1 week ago) (2 children)

Delta-V Budget assuming standard parts

Getting anywhere in space requires ∆V, think of it like "gas needed" to go somewhere in a car, in an extremely simplified form.

The long form is a dimensionless change in velocity. You can point to any object in the night sky and calculate the ∆V required, like Jupiter.

In this case, NASA needed to go say, 384 miles to get to Jupiter and made it with less than 4 miles of fuel remaining using the car analogy. That's a shocking degree of accuracy.

They then purposefully coasted into the gravitational terminus of Jupiter terminating the mission using the final 1% of fuel, while studying the planet over a number of years.

In space, informally, and also because I'm personally somewhat awful at space, a 20% margin of error in ∆V would be considered "good" for us mere mortals, because we need to have wiggle room for errors, mistakes, and course corrections.

(Flipping a lander or rover over on the Moon is considered to be average performance, see: IM-2)

[–] [email protected] 7 points 1 week ago

I'll have you know I managed to land Jeb on mun with exactly zero fuel remaining, so suck it NASA.

[–] [email protected] 2 points 1 week ago

20% is kinda a lot ngl, we could probably do better.

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