How to get to Minmus?

[kacperrutka26]

Hello everyone!

I need help, I already went to the mun lots on .16 but I still cant get to minmus. I looked for it in the forums but I didnt find anything. Are there any simple ways I can get there? I already got a rocket to get there but I need help how to meet up with it.

Thanks!

[neistridlar]

What I usually do is launch as if I am going to the mun, except I get my mun periapsis as low as possible, when doing the TMI burn. That will slingshot me in to a much higher orbit. From map view I align my view so that my orbit and minmus orbit make a perfect cross, and wait until my ship is at that cross. Then I burn north or south to change my orbit so it aligns perfectly with minmus orbit (this is called a plane change maneuver*). Now I just wait til minmus is some 20-45 degrees ahead of me, and expand my orbit by proburning until the patched conics tells me that I will enter minmus SOI. The rest should be easy to figure out.

This is not the only way, but I think it is one of the more efficient ways. Hope this helps.

[bsalis]

You get to Minmus the same as you get to Mun.

Only difference is you need to adjust your inclination like neistridlar points out.

See this...

http://en.wikipedia.org/wiki/File:Orbit1.svg

To change your inclination you need to do a burn where the target inclined orbit intersects the plane of reference of your current orbit. You do the burn in a direction perpendicular to your orbit. So when orbiting around the equator you do north or south, which on the Nav Ball is between the green markers, on the line where the top (up) and brown (down) meet. Use your map view scrolled out so you can see the purple Minmus orbit line to visually judge your inclination against it so you know when to stop the burn.

Damn, now that I read that it makes is sound harder than it actually is... mebe theres a vid around. It\'s not that hard.

Anyhows, good luck on your Minmus landing.

[maro]

My way to minmus...worked every time...sometimes takes longer but works...

Minmus orbits at 46.400km

1) I set my apo to that 46.400

2) then looking where minmus is

3)

a) is it in front of my apo then i have to be a bit faster so i produce a (near) circular orbit a little smaller ... something like 45.500x46.000 or so

is it behind of my apo then i make a little slower/wider (near) circular orbit....lets say 46.800 x 47.500 about....

4) when the orbits are (near) parallel yo can adapt to a more closer orbit but usually minmus grav catches you this way

[hen3ry]

My default strategy for Minmus is what I call the collision course method - it\'s not really the 'right way' to do it, but it works.

Launch to a projected Apo of 46,400km (-ish) fully vertical. This will put you in a suborbital trajectory, unless (1) you\'re very lucky and happened to launch at just the right time to hit Minmus (rare) or (2) you\'re going to be thrown off by the Mun (also rare, but slightly more likely to occur).

At approximately 2,000km (you can do it anywhere along the path really) altitude, using the map, I make my initial North-South adjustment burns. I burn about 5%-10% throttle, pointed to either 0 or 180 bearing on the navball, along the horizon. This will adjust the projected apo north or south without greatly altering its projected altitude. The target is to put the Apo directly on Minmus\' orbital path. A series of fine adjustments is needed. (RCS burns would work too here, but I seldom bother with RCS).

Once apo is aligned, I burn again prograde or retrograde to put my apo at 46,400km (ish) (the north-south burns can throw it off). If necessary, I repeat the adjustments until it\'s 'good enough'

Now, timewarp to near the apo. Using this method, your relative velocity will be almost nil, due to the suborbital nature of your trajectory. Turn the ship to exactly 270 degrees, on the horizon, and full burn until your velocity is 274.1 m/s (ish). If you were perfect, you should be on a direct collision course with Minmus. More likely, however, you will be on a course to enter Minmus\' zone of influence, from where a properly timed retro burn pulls you into a stable orbit.

The downside to the method is, naturally, you will be entering Minmus\' ZOI with a velocity of about 548 m/s relative to Minmus. Still, I\'ve almost never had a problem performing the required retrograde burn to enter Minmus orbit.

Why do I say this is a wrong method? Ideally, realistically, one would perform the adjustments while in Kerbal orbit, and time a transfer burn to Minmus from there, similar to the Munrise method. The reason would be, if there was a failure, it would be far easier to recover your kerbonauts from near Kerbal orbit, than it would be at 46,400 km away. (and if you miss your adjustments, you don\'t have a second orbit to try again, since you spend much of the trip sub-orbital). I suspect its also a bit inefficient with the delta V, since you\'re making essentially two correction burns - one in the polar direction to get the eccentricity, then one to set the collision course.

One could use the same method to reach Mun (the eccentricity adjustment being skipped as unnecessary), but you would need to Apo at 11,400 km, and then do a 270 burn to 542.5 m/s - and your velocity relative to Mun would therefore be nearly 1100 m/s. I prefer the Munrise method for Mun, but I haven\'t found a good equivalent for Minmus.

Summary: There are better ways to do it, efficiency-wise, I\'m sure. But that would require doing rocket sciency math. xD

[maltesh]

Because of the way orbital periods work, you can use the Munrise Burn Method to get you to Minmus.

Basic Elements of Munrise Burn:

1. Get into eastward Low Kerbin Orbit (aim for about 100km circular orbit, but the method is extremely forgiving with the Mun)

2. Wait for the Mun to rise over the horizon.

3. Burn in your direction of velocity o until your apoapsis is on or about the Mun\'s orbit.

4. Coast to apoapsis, and wait. The Mun will be along shortly and sweep you into its large SOI.

It\'s basically the most fuel-efficient method to get you to the Mun, and puts your spacecraft on the surface (assuming you know what to do from there) in about 7-9 hours from launch.

The MinmusRise burn is basically the same; you only need to be going about 80 m/s faster to put your apoapsis in the range of Minmus\' orbit than you do in the Munrise Burn, and

1. Get into eastward Low Kerbin Orbit

2. Wait for the Minmus to rise over the horizon.

3. Burn in your direction of velocity until your apoapsis is at Minmus\' orbital radius.

4. Coast to halfway out or so, and do a plane-change that puts your apoapsis on Minmus\' orbit. You may also need to adjust your velocity a bit to find the intercept, but with v0.15\'s patched conics, it will be fairly obvious when you do.

5. Coast the rest of the way, get swept up into Minmus\' SOI, and land.

Thus is ultimately both more time-efficient (putting you on Minmus in about 2 days from launch), and fuel efficient than using a Munar slingshot. As mentioned before, you only need about 80 m/s more to burn into a Minmus intercept than you do into a Munar intercept from LKO, and if by some miracle, you don\'t manage to spend more than that in delta-V adjusting your Munar flyby trajectory to give your exit path an apoapsis Minmus orbit, you /will/ spend more than that in delta-V circularizing at Minmus\' orbit

As for why I advocate doing the plane-change late in the transfer; The faster you\'re moving, the harder an orbital plane change is, and the farther out you are, the slower your spacecraft\'s moving, and at 30,000 km over Kerbin, you\'re moving pretty darned slow. You don\'t have to orbit in the same plane as Minmus to intercept it, you just have to cross the plane at a point where Minmus is at the time you cross it.

[Monger]

I found it considerably easier to land on Minmus, when you align your orbit on the same plane like Minmus' orbit. Navigating in threedimensional space can be tricky, and tilting an ellipse works best at its smallest radius.

So, my advice:

1) go into orbit around kerbin at ca. 150.000m

2) use the orbital map to find out where Minmus' Orbit and yours are at the same height. For this, rotate around Kerbin until Kerbin, your Orbit, and Minmus Orbit are crossing. Move your spaceship until you are at this point

3) Accelerate north or south, until both orbits align. The better you do this, the less issues you'll have once you expand your orbit

4) Pick a point about 30 degrees in front of Minmus, draw a line from there through kerbin to the point where it crosses your orbit. Move to this point, and accelerate horizontally along your orbit, until it crosses Minmus path. If you aimed precisely enough, you will get caught in Minmus' gravity, and can decelerate from there.

[vexx32]

My method is a little more... shall we say... impatient. On my first attempt, I knew full well that not having accounted for Minmus' position on launch or during any of my transfers, I could well end up playing catch-up with it for years on end. So... This is what i did.

1. Achieve Kerbin orbit.

2. Burn prograde at Apoapsis or Periapsis (yeah, wherever it happens to be, doesn't matter yet) until your Apoapsis reaches 46,400,000m or thereabouts (there's some margin for error here, but not too much).

3. Wait until you reach your new apoapsis. Not how slow your ship is travelling.

4. Orient your ship retrograde (should be 270 on the navball, assuming you launched 090 -- East)

5. Burn until you've changed orbit directions, and continue until your periapsis has gone up to around the same altitude as your apoapsis. Again, there's some margin for error.

6. Look in Map view for where your orbit crosses over Minmus' (where the planes of the orbits intersect) and wait until you reach one of these points.

7. According to where you are in your orbit, you'll nee to burn either North (000) or South (180) to move the point of the orbit you're travelling towards up/down respectively.

8. Align your orbital plane pretty closely with Minmus'.

The patched conics should be able to show you an encounter pretty much straight away. As soon as it does, you can stop burning.

However, since you're orbiting in the opposite direction to Minmus, you'll need to be ready to slow down a fair bit (you'll have about 200m/s or so to cancel out) in order to orbit Minmus or land.

[LMUBill]

What exactly is Minmus' orbital angle off of the "zero" plane that Kerbin and the Mun orbit? I want to try to go directly into that plane while lifting off. (Like NASA/RSA do when launching to the ISS.)

[sal_vager]

LMUBIII, I couldn't tell you exactly, but it looks like about 5 degrees.

[simplemunrockets]

You're very close. The exact inclination is 6 degrees.

[KevinTMC]

How to get to Minmus?

Practice, man. Practice.

(Oh, wait...you said "Minimus", not "Carnegie Hall", didn't you...)

[nhnifong]

2. Burn prograde at Apoapsis or Periapsis (yeah, wherever it happens to be, doesn't matter yet) until your Apoapsis reaches 46,400,000m or thereabouts (there's some margin for error here, but not too much).

Why on earth would you do that when you could just take off in the other direction to begin with...

[Endeavour]

Why on earth would you do that when you could just take off in the other direction to begin with...

It is much easier to switch the inclination of your orbit when its velocity is lower.

[robly18]

When I want to go to Minmus I simply make an orbit and attempt to get my apoapsis line up with minmus' orbit. On my first time I actually did a gravitational slingshot maneuver on the Mun to help me get there. Anyways, simply line your orbit up with minmus, time warp and wait until you're on a collision orbit. Works fine for me.

[handelin]

I´m wondering how these things handle in real life.. When watching the Curiousity landing movie by NASA it looked as they went directly into space without going into Orbit first. Maybe it´s just simplified for the viewers but does anyone know if that´s the case? It should definitely be possible to reach Minmus by just going at the right direction when leaving the atmosphere if the launch is executed at the right time at the right angle.. But I guess it involves some heavy calculations.

Anyway my way of getting to Minmus have been to first reach the Mun and change the inclination from there. If you time it right you can slingshot away from the Mun and reach Minmus.

[erkha343]

Launch satellite into a 5,5* orbit, inclined with Minmus, use Minmus orbits to confirm it's the right angle of 5,5* and not pointing the other way, then time your launch when KSC is lined with the satellite, and launch it in an 85* HDG, until it reaches a 100km orbit, tweak the orbit until it matches 100% the orbit of the satellite, then burn 30-45* ahead of Minmus.

* is degrees