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.
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)
I’ll have you know I managed to land Jeb on mun with exactly zero fuel remaining, so suck it NASA.
20% is kinda a lot ngl, we could probably do better.