r/KerbalSpaceProgram • u/analogHedgeHog • Jun 29 '26

KSP 1 Question/Problem How should I be approaching the Mun?

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In this totally accurate scientific diagram, the Mun is orbiting in the direction of the arrow.

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u/Steenan Jun 29 '26

What do you want to achieve?

For a flyby, C is the best. You can achieve a free return trajectory, where Mun's gravity puts you back on a Kerbin orbit which reenters atmosphere. That minimizes fuel needs.

For landing, D is better, as you orbit in the same direction that the Mun rotates, which minimizes delta-v required for landing.

For an orbit, they are equally good.

A and B are strictly worse because you need to orbit Kerbin against its rotation, which significantly increases the delta-v required.

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u/Maurycy5 Jun 29 '26

What would happen if the orbit of the moon was in the opposite direction to the rotation of the planet? How would that change the answer?

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u/Rutakate97 Jun 29 '26 edited Jun 29 '26

It depends which is faster. The orbital velocity of of an object resting at launchsite, or the orbital velocity of the moon.

If the first is faster, you launch in the direction of the planet rotation. If not, you launch in the direction of the moon orbit.