Stupid Question- orbit direction

[Stewcumber]

All planets and moon in KSP orbit anticlockwise when looked from top down. Th is kind of 'left / east' when looking from the KSC in default map view. Do I want to be orbiting Kerbin in a clockwise (i.e 'intercepting Mun') or anticlockwise (i.e. catching up to the Mun) direction for trips to Mun and Minmus?

Cheers!

[Pecan]

1. It is always easier to launch into an anti-clockwise orbit from Kerbin because you gain momentum (300m/s ?) from the existing rotation of the world.

2. To go to Mun/Minmus you need to raise your apoapsis until it reaches their orbit. IE; burn prograde at the opposite point in your Kerbin orbit - whichever way around it is.

3. When you get to the target you'll probably want to circularise your orbit around it. This is easier if you're 'catching up a bit' rather than 'whizzing past in the opposite direction'.

So - always* orbit Kerbin anti-clockwise.

[*Unless you don't want to]

PS: waves from the coast further East of you :-)

[Red Iron Crown]

Anticlockwise will have lower delta-V requirements, so it's usually the way to go. Less energy to launch, same energy to transfer, less energy to capture and land.

When you do an anticlockwise Mun or Minmus transfer, you'll notice that you don't catch up to them, they catch up to you.

[Taki117]

In all honesty it really doesn't matter. you will spend a little more dV to get into a clockwise orbit around Kerbin (And any other body you are orbiting) because of the rotation of the planet. (For kerbin it is 174m/s, for the mun it is 9m/s) but considering most rockets are over engineered anyway it's not that big a loss. The issue comes when landing. If you are orbiting with the planets rotation (Anti-clockwise) then you will have to put the point at which your orbit intersects the ground before the point where you plan to touchdown. (Undershoot your LZ) whereas for a clockwise orbit you will need to overshoot the LZ.

[Claw]

Also, I think orbiting and intercepting retrograde can shorten your flight time.

My first landings on the Mun were retrograde, because it is pretty easy to literally line up and crash onto the surface. The orbital alignment felt much less complex than trying to "meet up and orbit" when I was first learning how.

[Vanamonde]

If you go anti-clockwise (prograde with respect to the planet's rotation), you'll be overtaking the moons from behind, with a bit of speed boost from the planet's rotation. If you go clockwise (retrograde), you'll be fighting the planet's rotation and scrambling to manage a head-on collision when you arrive at the moons. Therefore, it's easier to go prograde for the same reason that planes take off over the bow of a carrier and land on a carrier by approaching the ship from behind.

[pantner]

can't remember the names for the directions, but I've seen people say that if going interplanetary then for the outer solar system you should turn to 90 degrees for your gravity turn, if you are going to the inner solar system then you should turn to 270 degrees.

[kahlzun]

It doesn't matter either way: launching east (90) saves you ~ 300dV

[Red Iron Crown]

can't remember the names for the directions, but I've seen people say that if going interplanetary then for the outer solar system you should turn to 90 degrees for your gravity turn, if you are going to the inner solar system then you should turn to 270 degrees.

No, it's better to go East for both scenarios. The dV saved by building on Kerbin's rotational speed rather than working against it is beneficial whether you're heading inbound or outbound. The only difference is where in your orbit you do your interplanetary burn (angle to prograde).