Comment on Lmao
expr@piefed.social 6 hours agoI assume it’s not just about the gravity, but also the much larger radius of the planet would mean much larger distance from the surface, and thus much more fuel needed.
That’s, uh, not really how that works. A taller atmosphere would mean you have to go through more of it, but unless it’s not a terrestrial then the atmosphere won’t be that much taller.
If it is a non-terrestrial planet, it’s unlikely anyone would be building rockets on there to begin with.
If it has a higher gravity would the atmosphere technically be lower since it will squish up closer to the planet?
And your username would also be relevant.
You're sort of right. The change in distance from the surface is insignificant, but a spacecraft orbiting a bigger planet has to travel further with each orbit so its speed must be faster to avoid falling out of orbit, even if the gravitational acceleration at its orbital height is the same.
potatopotato@sh.itjust.works 6 hours ago
That’s how how…what???
F = G * (m1 * m2) / r^2
expr@piefed.social 2 hours ago
I stated an assumption and was contributing to the conversation. Even if that assumption is incorrect, there’s no need to be a dick about it.
It seems like a larger atmosphere would result in a longer duration exposed to atmospheric drag, thus requiring more fuel to overcome it.
lemmyman@lemmy.world 5 hours ago
Escape velocity does scale with (square root of) radius so its not a dumb thought.
And I’m not a rocket surgeon but I could imagine earth rockets might be operating near some physical limits that make 50% (or whatever) infrasible.
en.wikipedia.org/wiki/Escape_velocity
Lojcs@piefed.social 4 hours ago
Wikipedia says
energy = GMm/r.if
g=GM/r²,energy = mgr, proportional to r given g is constant.PREVIEW_HERE
My previous comment was wrong, I derivated while integrating.
PREVIEW_HERE
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