Furry
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Little extra involvement isn't being in the orbit of mars, imo. You went all the way there, might as well go for the extra 20%.
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The Astronomy Thread
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whatever, blah blah it just needs to happen BEFORE I FUCKING DIE !!!!! Sorry I just seem to be falling apart , I want this shit to happen NOW!
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Big Phoenix
Pronouns: zie/zhem/zer
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Seems like it would be a win win imo. The legwork and logistical setup to enable starship to land on mars is a decade+ away. You can go to Deimos and back with significantly less investment. Go there, score brownie points and hyper up every would be investor for cash to support your Mars landing in that decade+ time frame.
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Gavinmad
Mr. Poopybutthole
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Extra 20%? A round trip to the surface from Mars intercept is just shy of 10000 dV, Deimos is only 2000 dV and Phobos is about 2500 dV. You need 5-6x more fuel for a Mars landing than you do for one of it's satellites.
Of course this isn't KSP so there's no particular benefit to landing on Deimos or Phobos like there is to landing on Ike but it's a far simpler mission in terms of how big a payload you have to move to Mars orbit and back.
Of course this isn't KSP so there's no particular benefit to landing on Deimos or Phobos like there is to landing on Ike but it's a far simpler mission in terms of how big a payload you have to move to Mars orbit and back.
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Kiroy
Marine Biologist
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So technically after the first few proof of concept missions to mars and getting a small colony going at massive expense, you could then start loading up the moons with gear until the mars colony had a way to create it’s own fuel to go start ferrying it down.
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Captain Suave
Caesar si viveret, ad remum dareris.
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(Edit: Found a better source right after posting.)
Delta-V map of the solar system. Not sure where your numbers are from, but this indicates it's about 25% more expensive in dV to land on Mars than either of the moons. Aggregate all the nodes over the total route from origin to destination.
At least 70% of the energy is just getting past low Earth orbit. Gravity is a bitch.
File:Solar system delta v map.svg - Wikipedia
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Gavinmad
Mr. Poopybutthole
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Might as well just stash stuff in low Mars orbit. The dV cost to get to Mars orbit is not that much higher than the cost of going to Phobos or Deimos orbit, it's landing and taking off again where the massive dV difference comes in. When live people aren't involved the range of viable possibilities to get things down to the surface is much wider. First thing that comes to mind is you could put a payload in a slightly elliptical orbit with it's periapsis just barely dipping into the atmosphere and let it take several weeks to finally slow down enough to de-orbit.
I was using a map that starts at Earth transfer. Which isn't entirely fair and I should have been starting at LEO, but either way you don't include surface to LEO dV cost.(Edit: Found a better source right after posting.)
Delta-V map of the solar system. Not sure where your numbers are from, but this indicates it's about 25% more expensive in dV to land on Mars than either of the moons. Aggregate all the nodes over the total route from origin to destination.
At least 70% of the energy is just getting past low Earth orbit. Gravity is a bitch.
File:Solar system delta v map.svg - Wikipedia
en.m.wikipedia.org
View attachment 545236
Captain Suave
Caesar si viveret, ad remum dareris.
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Why? Because that leg is covered by first stage fuel? It's still part of the trip even if you're using separable boosters.
Gavinmad
Mr. Poopybutthole
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Because it has nothing to do with the trip to Mars. It could conceivably take 3+ launches to get all the pieces of the mission into orbit but that doesn't add 30k dV to the trip.
Captain Suave
Caesar si viveret, ad remum dareris.
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I guess I don't understand how you get to Mars without first getting off Earth.
No, but all three launches would experience the delta v of the surface to orbit leg.
Captain Suave
Caesar si viveret, ad remum dareris.
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It sure mattered for the planning and design of the LEM and the mission as a whole.
If that's the logic, why count anything before where the presumed lander/entry vehicle would separate from the transit bus in Mars orbit?
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Gavinmad
Mr. Poopybutthole
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I meant to refer to the CSM rather than the LEM but this is going nowhere very slowly so I'm gonna stop wasting my time.
Cybsled
Naxxramas 1.0 Raider
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Realistically you'd have to match the orbital velocity of one of them from a launch of Earth, which is significantly slower than the velocity usually used for Earth-Mars transit missions, which means you'd need to slow down significantly. Since they have negligible gravity, you can't use the "moons" themselves to do that.
It's also theorized they might be effectively loose rubble piles weakly held together
They might be targets in the future, but as Furry mentioned, they aren't really that interesting compared to other objects (or even asteroids) in the solar system.
Gavinmad
Mr. Poopybutthole
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A mission to Phobos or Deimos would be nothing like that. There's a dV chart on this page that shows the lower capture cost for Phobos or Deimos compared to Mars, although I prefer the subway map format as it's quite a bit easier to read.
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Ukerric
Bearded Ape
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The thing is, rendez-vous with asteroids and even bringing back stuff has been done. The only difference would be that those asteroids are in orbit around Mars instead of the Sun.
But if it's intended to scam... sorry, hype investors for support, sure, why not?
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