Do any of you have a database of DeltaV to and from each celestial body?

[Amagi82]

I'm working on making a newer, shinier, better Android app, and I was planning to include the requred Delta V for a transfer and a landing to and from each celestial body. I've found plenty of resources on Kerbin to elsewhere, but nothing on other planets. Anyone have this, or remember the calculations necessary to figure them out?

Thanks!

[Taki117]

This dV map should get you going. Just add all the numbers from where you are to where you want to go and double it.

[Claw]

This dV map should get you going. Just add all the numbers from where you are to where you want to go and double it.

I like this dV map a lot too.

Just make sure you read the notes off to the right as they explain what the numbers mean. Also realize that each dV map uses slightly different assumptions. And only double the numbers if you're actually calculating the "there and back" part.

[Guest]

This dV map should get you going. Just add all the numbers from where you are to where you want to go and double it.

The numbers for Tylo seem quite a bit low on that map. I think it's closer to 3000 dv to land. Anyone else been able to land on Tylo with 2270 dv?

[Amagi82]

The problem with that delta v map is that it is Kerbin-based, and doesn't allow for a direct trip from, say, Moho to Jool. Have you seen anything, for KSP or otherwise, that lets you just plug in raw data and get accurate results, using teh maths?

[Zeroignite]

Here ya go

[benschwab]

Here ya go

That gives more information but it still doesn't allow one to go from a moon to a body that isn't another moon in the same planetary system of the planet itself.

I am quite impressed by the program never the less.

[bernierm]

That gives more information but it still doesn't allow one to go from a moon to a body that isn't another moon in the same planetary system of the planet itself.

I am quite impressed by the program never the less.

As far as the departure from a moon goes, you could probably approximate by adding the moon's escape velocity to the delta v needed from an orbit around the moon's planet at the moon's orbit (ie, for mun, that would be 12,000,000 m). Escape velocities are listed in the wiki.

[XiXLLAMAXiX]

That gives more information but it still doesn't allow one to go from a moon to a body that isn't another moon in the same planetary system of the planet itself.

So, you'd want dv for direct transfer from (for example) Ike to Kerbin? Because that's actually pretty hard to calculate accurately.

What I normally do in some situations is figure out the height of the moon above it's host's surface (for ike, this is about 3200km) and plug that height into the alexmoon calculator (ejection dv for duna(3200)->kerbin(100) is about 574), I subtract the orbital velocity of the moon (Ike's is avg 320) which lets you know that you need to leave ike's SOI traveling at about 254m/s. This gives you a lower bound for the dv required. Using orbital kinematics, we can find that a good upper bound for the dv required is (254 <known final SOI velocity>)(1049598 <height of sphere of influence of ike>)/(130000 <equatorial radius of ike> + <whatever starting height you're going from>) - ((1.857e10 <gravitational parameter of ike>)/(130000 <eqr of ike> + <start height>))^(1/2) which calculates to 1673m/s (from an orbit immediately above surface level on ike). the above formula I provided should get you rather accurate values in this case, but know that this makes several assumptions such as assuming that ike is properly lined up so that you can eject into a transfer exactly at the alexmoon launch window time, which is not necessarily very common. You can use this methodology to find moon->other body dv. I don't feel like figuring out moon->other body's moon at this point, =P

[benschwab]

I don't feel like figuring out moon->other body's moon at this point, =P

That's fine by me. I'm impressed by the program as it is. I thank whoever wrote it.

[Amagi82]

So, you'd want dv for direct transfer from (for example) Ike to Kerbin? Because that's actually pretty hard to calculate accurately.

What I normally do in some situations is figure out the height of the moon above it's host's surface (for ike, this is about 3200km) and plug that height into the alexmoon calculator (ejection dv for duna(3200)->kerbin(100) is about 574), I subtract the orbital velocity of the moon (Ike's is avg 320) which lets you know that you need to leave ike's SOI traveling at about 254m/s. This gives you a lower bound for the dv required. Using orbital kinematics, we can find that a good upper bound for the dv required is (254 <known final SOI velocity>)(1049598 <height of sphere of influence of ike>)/(130000 <equatorial radius of ike> + <whatever starting height you're going from>) - ((1.857e10 <gravitational parameter of ike>)/(130000 <eqr of ike> + <start height>))^(1/2) which calculates to 1673m/s (from an orbit immediately above surface level on ike). the above formula I provided should get you rather accurate values in this case, but know that this makes several assumptions such as assuming that ike is properly lined up so that you can eject into a transfer exactly at the alexmoon launch window time, which is not necessarily very common. You can use this methodology to find moon->other body dv. I don't feel like figuring out moon->other body's moon at this point, =P

Thanks! I'll plug some numbers into that formula after I get some sleep here. Many of the fancy calculators I've seen give a few values I know to be completely wrong, which makes me question the accuracy of all the other values. Unless someone beats me to it, I'll post the numbers when I finish.

[Taki117]

That gives more information but it still doesn't allow one to go from a moon to a body that isn't another moon in the same planetary system of the planet itself.

I am quite impressed by the program never the less.

If I am understanding what you are asking for, you are looking for something that gives you the dV to go from the Mun, to Minmus yes?

With the dV map I gave you does just that.

580 for munar liftoff, 230 for escape, 80 for munar transfer, 70 for minmus transfer, max of 340 for plane change , 90 for escape, 70 for low orbit, 180 to land on Minmus.

580+230+80+70+340+90+70+180 = 1640

Don't forget to add a little bit of wiggle room and you are good.