Really wierd path behavior going to the mun.

[gsonnenf]

Hello, so I set up a shuttle using maneuvers to get to the mun. I found the paths of the orbit lines very bizarre. I was approaching to the front of the moon with my velocity going forward (the yellow dotted line) then at the mun entry point, it warps me across the screen and now my velocity vector is going the other way (from the start of the pink dotted line) and I'm headed in the opposite direction of the mun orbit.

Is this a bug on my system or is it does KSP just do weird discontinuous orbits because their programmers didn't make the changes between conic approximation regions line up correctly?

Edited October 1, 2015 by gsonnenf
answered

[TechnicalK3rbal]

IIRC, there's a setting for this in the Config file called conic draw mode or something similar. It changes the behaviors of interplanetary (Though I guess it's any object. Inter body?) orbit lines.

- - - Updated - - -

Heres a link to another thread on the same topic.

Edited September 22, 2015 by TechnicalK3rbal
Spellcheck

[mdkendall]

It is correct, and there are no discontinuities in your position or velocity in space, but it looks odd because each line segment is drawn relative to a different reference frame.

Before you reach the Mun's SOI, while you are still in Kerbin's SOI, your orbit is drawn relative to Kerbin. You see another section coming up which represents your path within the Mun's SOI, and this is drawn relative to the Mun, centered around where the Mun is right now. So it looks disconnected from your current orbit. But as you proceed the Mun will get closer, and that disconnected segment will move closer, until at the moment you enter the Mun's SOI the entry point on that segment will exactly align with your current position.

At that moment the view switches and your current orbit starts being drawn relative to the Mun. It looks as though you have changed direction but you haven't. What has happened is that before the SOI change your orbit was drawn relative to Kerbin, and after it your orbit was drawn relative to the Mun, and, here is the key, the Mun is moving relative to Kerbin.

Your current segment, the orbit you are on right now, is always drawn relative to the body you are currently in orbit around. Future segments are usually drawn relative to the bodies they relate to, around their current position. But there is some flexibility in this; it can be changed with the conic draw mode setting.

Regardless of how you display it, the path your vessel takes through space is always the same, and there are no actual discontinuities in position or velocity.

[RCgothic]

As mentioned, it's only an apparent discontinuity caused by changing reference frames. Currently displayed are your flyby path relative to the Mün and your orbit around Kerbin (relative to Kerbin) once you complete your flyby.

The two will precisely intersect when you get to the point of changeover. Any change in velocity vector at that point is illusionary.

[Snark]

+1 to previous posters' comments. It's also worth noting that it's a good thing that Squad implemented it this way, or the game would be confusing and difficult-- if you're doing a Mun flyby, you really want to see your trajectory relative to the Mun. In other words, this is the least confusing way of presenting what's going on.