Getting into polar orbits of other bodies.

[Sharkman Briton]

Hi, I'm trying to make a fuel station on Minmus, and I need to do scans of the planet, Is there a good way to get into a polar orbit of Minmus? The only way I can think of is just getting into orbit around Minmus and then doing a big long expensive burn to change my inclination alot, but thats not very good, no?

I can also think of trying to get lucky and capture Minmus while in a polar orbit of Kerbin, but you would need to be EXTREMELY precise and lucky.

Any ideas? Thanks in advance.

Edited October 3, 2015 by Sharkman Briton

[Tex_NL]

Getting to ANY polar orbit is actually very easy.

1. Launch into the 6 degree Minmus plane.
   
2. Make you transfer burn exactly like you would otherwise.
   
3. As soon as you enter Minmus' SOI make your plane change.
   
4. Descent to periapsis and circularize.
   

Make your plane change as high up as possible while you're still going very slow. At that point the dV cost will be negligible.

This works for ANY planet or Moon.

[bigcalm]

Because orbital velocity of Minmus is pretty low, completely changing inclination should only cost you around 300 ms^-1 ÃŽâ€v . You can minimise this further - when encountering Minmus: 1) Burn at periapsis such that you achieve an eccentric orbit around Minmus with low periapsis and high apoapsis; 2) Do an inclination change around apoapsis; 3) Circularise at periapsis. This should mean that you add only ~ 100ms^-1 ÃŽâ€v to your mission budget.

[Sharkman Briton]

Okay, thanks!

[Kryxal]

For that matter, you can make the plane-change maneuver well outside the SoI, though it's probably going to be more difficult without something to allow editing nodes.

[mattssheep4]

I know this is already partly answered, but if you're not aware of this already, if you get a close encounter with Minmus (doesn't have to be a close one, but it has to enter Minmus' SOI), make a maneuver node at least halfway out to Minmus, then focus view on Minmus, open the maneuver node up again, and adjust the node so that the orbit goes above the north or below the south pole. This way, it doesn't really matter what orbit you start in from Kerbin.

Edited October 3, 2015 by mattssheep4

[Highguard]

For that matter, you can make the plane-change maneuver well outside the SoI, though it's probably going to be more difficult without something to allow editing nodes.

Manoeuvre nodes are editable. Just click on one to open it. Mousewheel over a direction indicator (pro/retro-grade, (anti)normal, radial-in/out). The easiest way to do it is to set-up your transfer manoeuvre as normal, just so you get an intercept with the target. Then double-click the target to shift focus to it (the node will close). Adjust your view so you can see the predicted-orbit line at the target and the node at the same time. Click on the node to re-open it, adjust at will, click somewhere else to close it when you're happy.

Adjusting a predicted Minmus equitorial orbit to polar before you even leave Kerbin only takes a few m/s deltaV.