HELP: Mun orbit (through) center of Mun

[pdxoreg]

I keep having this problem that when I approach Mun and my orbit changes, the orbit goes through Mun and not around. How do I fix this problem? Thanks!

Edited November 4, 2013 by vexx32
Fixed image.

[vexx32]

Thread moved to Gameplay Questions and Tutorials. (and I fixed the image so it'd show properly)

Welcome to the forums

Generally speaking, when burning into an orbit, you need to be facing somewhere around the horizon markers on the navball. Your orientation is currently directly towards the Mun which, while it'll probably get you there, will result in a high speed impact. Reorient your ship so it's pointing... from the image, I'd say your best bet would probably to face West (270) on the horizon and then burn. It may take some adjustment to get a decent orbit from that. Once you have a stable orbit, you can fine-tune it using manoeuvre nodes

[Vanamonde]

To raise your orbit so that it is not a collision with the moon, you could 1) accelerate straight ahead until your speed will carry you around rather than through it, but then you would need to shed that speed again before attempting to land or orbit. Or, 2) you could turn 90 degrees away from Mun in the plane of your current path and burn to raise your apoapsis without changing your speed as much. But the best method is to 3) change your approach to Mun before you get there, because the farther away you burn to make the adjustment, the less fuel you will use. Experiment with maneuver nodes to plan your route while you are still orbiting Kerbin, and see how the line of your projected path through Mun's sphere of influence changes as you play with the maneuver node. It is quite helpful to get into the game's settings file and change the line

CONIC_PATCH_DRAW_MODE = 3

to

CONIC_PATCH_DRAW_MODE = 0

This will display the line of your path near Mun more clearly.

(vexx32 is giving you the same advice as my option #2, just in different terms. )

Edited November 4, 2013 by Vanamonde

[Kasuha]

The most effective way to avoid collision with Mun in this situation is to burn in radial out direction. If you place a maneuver on the trajectory ahead of you, it's the cyan circle with short lines stretching out.

(actually the most effective is to combine prograde and radial out, but using just one is simpler and the difference is not that great)

To prevent your trajectory getting distorted on passing the Mun (or whatever) SOI boundary, make sure you cross the SOI boundary at lowest possible time warp, ideally x5.

Edited November 4, 2013 by Kasuha

[pdxoreg]

Thank you for the quick response! And also for the advice it worked beautifully.

[Sirrobert]

Whenever you see an orbit you don't like, open up a manouver node and just play with all options. See what works best. That's how you learn what everything does.

It costs less fuel if you do this earlier. When you are still in Kerbin SOI, you can see the projected orbit you are going to get with the Mun. If there is no periaps symbol, that means your periaps is going to be inside the Mun. So just make a node and see if you can change that