Polar orbit questions

[Serenity]

So i was trying to figure out a simple way to have my polar orbits/transfers to other planets in the same plane.

Example: To avoid this https://imgur.com/a/BwI2Vh2

My brain literally broke down and if that wasn't enough, i wondered if the green vessel with the slower orbit will ever match the plane of the red one.

I am maybe thinking they will? but i cant figure it out.

Sorry if this has been asked before but i am kinda bummed out that i hit this wall and i am out of energy to search for it,

although i hope there are some simple things you can do to ensure they are in the same plane and i am just overthinking and missing the obvious.

Edited May 2, 2018 by Boyster

[GrouchyDevotee]

They appear to be in the same plane, but they are orbiting in opposite directions. They will eventually be in the same spot at the same time, but the game will probably not create an impact.

If you are trying to send an orbiter to another planet, or one of Kerbins Moons, and want it to achieve a polar orbit in a specific direction, set up a manoeuvre node before you enter the sphere of influence and make an insertion adjustment burn.

Make adjustments to the node until you have a polar orbit, then adjust the Peripsis altitude, if it's orbit is in the correct direction you're fine. If it's in the wrong direction Watch the Periapsis and reduce the altitude until it appears you will impact the surface, keep adjusting the manoeuvre node in the same direction until the Periapsis is back up to a safe altitude in the proper direction.

Edited May 2, 2018 by GrouchyDevotee

[Serenity]

Hmm, you made me think a way, maybe.

Maybe if i decide for Mun for example to always enter its sphere of influence from the north ''pole'', then the direction of my vessels will always be the same.

Right?

About the other part, i know that they will be in the same spot, what i am wondering is if after many many years, they will have the same direction if one orbit is slower than the other.

Which sounds crazy but i dont know why i bugged out in that.

Edited May 2, 2018 by Boyster

[GrouchyDevotee]

I really don't know the specific technical descriptions and terms, but here is my guess.

I believe that the first part will not be correct. If the first Satellite enters the Mun's Sphere of influence ( SOI ) in it's orbit around Kerbin closest to the sun, and the second Satellite enters the Mun's SOI when the Mun is at it's farthest point from the sun in it's orbit around Kerbin, then the satellites will be travelling in opposite directions if they both enter over the North pole. 

For the second part, if they are in the same plane then they will always be in the same plane, and will not wind up going in the same direction.

 

 

Edited May 2, 2018 by GrouchyDevotee

[Serenity]

You really broke my spirit man  hehe.

My brain hurts, i ll try what you said in your first post but i wonder, if i make the insertion burn right from the start to match the direction of my desire

what keeps me from having the wrong direction by the time i am doing the circularization burn.

Edited May 2, 2018 by Boyster

[Zeiss Ikon]

Your two satellites are not in the same plane (even if they appear to be).  If you express their planes as inclination, one is at +90 degrees, the other is at -90 degrees.  The cheapest way to get them together is to boost one so the apoapsis is near the edge of the SOI, wait until the satellite reaches that point, then burn to reverse the orbit (that'll be a tiny burn, potentially a few tens of m/s).  Wait again, and burn at periapsis to lower your apoapsis back to the correct figure.

[Serenity]

26 minutes ago, Zeiss Ikon said:

Your two satellites are not in the same plane (even if they appear to be).

I dont want to be rude just i never said they were in the same plane.I said i want to avoid that and match their planes when i am making planetary transfers, if there is a simple way to know how

to make the insertion burn correctly every time.

Edited May 2, 2018 by Boyster

[bewing]

There is no simple way to know how to match the planes when you enter the SOI.

The only time you can match planes is at the moment that your current trajectory crosses the plane of your target orbit. And until you have a closed orbit in your new SOI, there is no easy way to know exactly where that node is. When you are in a completely different SOI from your target orbit, that makes it even harder. The best you can do is set up an approximate manuever node, and then run it along your current trajectory to see how it impacts your final trajectory in the new SOI -- that will tell you approximately where on your trajectory you are crossing the plane of the target orbit.

[Zeiss Ikon]

The orbital planes will (or should, if the game's physics doesn't screw this up) remain fixed as the body's orbit carries it around its primary, so there's no general way to make an insertion burn (when coming from interplanetary space) to ensure matching planes, other than to look ahead for the plane of the satellite(s) already in place and match it.  There'll be two windows per orbit (one for insertion "above" the ecliptic, one for "below") when you can insert directly to the correct plane from a Hohmann transfer -- those will be the two times when the orbit "faces the sun".  More cometary transfers will have similar windows, when the orbit you're matching is at a suitable angle matching your encounter approach.

Otherwise, you'll just need to capture as high/eccentric as possible in the SOI and change planes where your velocity is low near apoapsis, in order to minimize the dV required to change planes.