Tutorial:How to get to Minmus

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This tutorial will attempt to teach you how to get to Minmus. It assumes that you have successfully completed a trip to The Mun, if you haven't I suggest you check out the tutorial.

Click here for a more up-to-date version of the Mun tutorial.

Introduction

Landing on Minmus is similar to landing on the Mun, with a few minor exceptions:

  1. Minmus is further from Kerbin than the Mun, which means:
    • More fuel is required from the trip between Kerbin's orbit and Minmus.
    • It has a slower orbit, making intercept velocities lower.
  2. Minmus is significantly smaller than The Mun, which means:
    • Landing on, and achieving orbit from Minmus is significantly easier due to lower gravity, requiring much less fuel.
    • Its Sphere of Influence (SOI) is smaller, which (plus the distance) requires more precision.
    • Its gravity is low enough that Reaction Control System alone is enough to correct a smaller spacecraft if it has been tipped over.
  3. Minmus has an inclined orbit, which means:
    • Direct injection has a higher failure rate.
    • Matching orbits requires a little extra knowledge about adjusting orbital inclination (and fuel).
  4. Minmus is not tidally locked to Kerbin which means.
    • More precision is needed when using direct injection when trying to land on a selected location.

Constructing a Minmus Rocket

The Upper Stage (Lander)

This stage should be much lighter than the one you would use to reach The Mun. Landing on Minmus and returning to Kerbin only requires about as much fuel put together as the landing phase of a Mun visit.

The Middle Stage (Transfer Burn)

Take advantage of the weight you have saved on your lander to pack more fuel for this one. You will need it for the trip between Kerbin and Minmus.

The Lower Stage (Launch)

This stage should not be much different than the one you would use on a Mun attempt. If you are not feeling confident about your middle stage, it never hurts to pack a little more fuel/thrust, adding boosters is never bad, you can use fuel ducts to get more Delta V.

Launching Into Kerbin's Orbit

Same as any standard launch, presumably on a much larger scale. Read the tutorial for how to reach orbit if you haven't already figured it out.

Minmus Injection

While it may not be absolutely necessary, matching your orbital inclination with Minmus makes it much easier to get caught in its SOI. Set Minmus as your target and burn perpendicular to your orbital plane at one of the nodes until they read '0.0' or 'NaN'.

Similar to the Mun guide, wait until Minmus is about 4-5 degrees over the horizon (20-40 degrees in the map) to begin your burn. It will appear as a small dot above the horizon. Burn until your apoapsis intersects Minmus' orbit, and (hopefully) you will be caught. Alternatively, you could also burn until your apoapsis intersects Minmus's orbit without changing your inclination. You probably won't see an encounter, so to fix your inclination for much cheaper, halfway to the apoapsis burn antinormal to drag it down until you see an encounter. This takes less thrust and is more efficient.

Landing on Minmus

Your orbit, retrograde burn, and landing will all be at much lower speeds than they would be at either the Mun or Kerbin. In fact, it's unlikely that you will (or should) reach speeds above 100 m/s at any point near Minmus, also move your retrograde vector pointing close to directly down. Try aiming for a frozen lake if you are looking for an easier landing, close to chart datum. Minmus' large mountain ranges make for more of a challenge elsewhere on the surface. And no, it's not a big ice cream!

Returning to Kerbin

Basic method

This is a crude but effective method, using slightly more fuel than the advanced method below. Begin a light burn until you escape Minmus' SOI, then apply retrograde thrust until your periapsis is below 65 km altitude on Kerbin. Happy Landings!

Advanced method

This method is cheaper on fuel.

  • Burn to raise the apoapsis to around 10,000m.
  • Burn prograde at apoapsis to achieve a low equatorial orbit.
  • When the craft is moving retrograde relative to Minmus's orbit around Kerbin, face prograde and burn again to escape velocity.
  • Keep burning until your periapsis around Kerbin is below 32,000m.
  • You will now be on a trajectory towards Kerbin. You will not need to burn again to re-enter the planet's atmosphere.

See also