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There is a delta-v map (not to scale) of our solar system that could be used as the basis of this: https://www.reddit.com/r/space/comments/1ktjfi/deltav_map_of

by fyfy18 7y ago

There is a delta-v map (not to scale) of our solar system that could be used as the basis of this: https://www.reddit.com/r/space/comments/1ktjfi/deltav_map_of_the_solar_system/ https://www.reddit.com/r/space/comments/1ktjfi/deltav_map_of...

JetSpiegel 7y ago
Direct link to the image: https://i.imgur.com/SqdzxzF.png https://i.imgur.com/SqdzxzF.png
throwaway2048 7y ago
One of the more interesting consequences of orbital mechanics is it takes far more delta-v to get close to the sun, than it does to leave the solar system entirely. Think about this in terms of how fast the earth is moving to avoid "falling into" the sun, anything that leaves the earth has that velocity too.
- DavidSJ 7y ago
  If you do a Hohmann transfer — the most basic sort, used by most Δv calculations — from Earth to the Sun, yes. But if you give yourself solar escape velocity (a savings of about 59% in your hyperbolic Earth escape velocity, which works out to a huge savings of about 18.9 km/s Δv if you do your burn in Low Earth Orbit), then once you get very far from the Sun you can stop yourself virtually for free, and fall straight down. The whole trip would take decades though. The same basic idea works for reaching any inner object orbiting any body. In practice you can probably do better by aiming for a planet and slingshotting, but that gets more complicated.
bjelkeman-again 7y ago
This illustrates why being in a Earth orbit is really “Halfway to anywhere” [1] in the solar system. Well, at least to where you would like to land. [1] A book by Harry Stein about single stage to orbit attempts. https://en.m.wikipedia.org/wiki/G._Harry_Stine https://en.m.wikipedia.org/wiki/G._Harry_Stine
mcv 7y ago
What's funny is that in terms of delta-V, the surface of Deimos (Mars' second moon) is actually closer to us than the surface of the Moon. Of course in travel time the distances are very different. Delta-V is not the only factor that matters.
- PhasmaFelis 7y ago
  Interesting. How does that work for Deimos specifically? I've read that landing on Mars takes less delta-V than the Moon because you can aerobrake, but that doesn't apply to Deimos. Is that because of its nearly nonexistent gravity, or is there some other factor?

by fyfy18 7y ago

JetSpiegel 7y ago

Direct link to the image: https://i.imgur.com/SqdzxzF.png https://i.imgur.com/SqdzxzF.png

throwaway2048 7y ago

One of the more interesting consequences of orbital mechanics is it takes far more delta-v to get close to the sun, than it does to leave the solar system entirely. Think about this in terms of how fast the earth is moving to avoid "falling into" the sun, anything that leaves the earth has that velocity too.

DavidSJ 7y ago
If you do a Hohmann transfer — the most basic sort, used by most Δv calculations — from Earth to the Sun, yes. But if you give yourself solar escape velocity (a savings of about 59% in your hyperbolic Earth escape velocity, which works out to a huge savings of about 18.9 km/s Δv if you do your burn in Low Earth Orbit), then once you get very far from the Sun you can stop yourself virtually for free, and fall straight down. The whole trip would take decades though. The same basic idea works for reaching any inner object orbiting any body. In practice you can probably do better by aiming for a planet and slingshotting, but that gets more complicated.

bjelkeman-again 7y ago

This illustrates why being in a Earth orbit is really “Halfway to anywhere” [1] in the solar system. Well, at least to where you would like to land. [1] A book by Harry Stein about single stage to orbit attempts. https://en.m.wikipedia.org/wiki/G._Harry_Stine https://en.m.wikipedia.org/wiki/G._Harry_Stine

mcv 7y ago

What's funny is that in terms of delta-V, the surface of Deimos (Mars' second moon) is actually closer to us than the surface of the Moon. Of course in travel time the distances are very different. Delta-V is not the only factor that matters.

PhasmaFelis 7y ago
Interesting. How does that work for Deimos specifically? I've read that landing on Mars takes less delta-V than the Moon because you can aerobrake, but that doesn't apply to Deimos. Is that because of its nearly nonexistent gravity, or is there some other factor?