# Getting further then the Mun

## Recommended Posts

I have gotten into orbit, docked stuff in orbit and I've been at the surface of the Mun. But how do i get further? i would like to start with Minmus then move onto Duna, so if anyone at there can help me, Thanks in advance.

##### Share on other sites

If you haven't already I suggest watching all of Scott Manley's videos on youtube. They explain alot.

##### Share on other sites

Going to Minmus is actually easier than going to the Mun, it takes less delta V in overall to reach surprisingly. Then to head off to other planets, two things.

Nuclear rockets. They're gonna save you a lot lot lot of fuel. Second, Phase angles. You might want to use an informative mod such as MechJeb (and Kerbal Engineer, I'm not sure if it gives that information though). Else, there's a lot of tools on the forum to calculate those fore you, and delta V maps will help you calculate how much delta V you need to get to the place you're heading. Maps like this:

##### Share on other sites

Thanks, but is there like an easy way to "calculate" where to put the orbit to get to minmus? because i would like to learn how to do this without a mod

##### Share on other sites

Thanks, but is there like an easy way to "calculate" where to put the orbit to get to minmus? because i would like to learn how to do this without a mod

Where to put the orbit? You mean the maneuver node? Well you proceed exactly like you would for the Mun: You set your maneuver node and stretch it out until it reaches Minmus's orbit, then you move it along your orbital path until you get an intersect. If you aren't getting any, it could be because it's at a point where the inclination is too high to get you in the SOI. If that's the case, just set Minmus as your target and burn north or south at the AN or DN to get the same inclination and do the same thing again. Although it would waste some fuel, so you could simply pass a few orbits and try again until you get your intersect.

##### Share on other sites

Ok, thanks to everybody that's helped me, now imma try to get to da minmus

##### Share on other sites

One thing to remember, sometimes surprisingly simple rockets can go a long way.

##### Share on other sites

The procedure for getting to Minmus is much like the Mun but with the inclination added:

1. Eastward parking orbit

2. Set target, adjust relative inclination to zero at AN/DN

3. Create maneuver node out to target's orbit

4. Drag maneuver node around your path until intercept

5. Fine tune node and execute

6. Retro burn to capture at Pe (make sure to give yourself a Pe above the surface, lower the more efficient)

##### Share on other sites

Maneuver nodes are a bit overwhelming when you first start this game, but once you've played around with them you find out just how incredibly amazingly useful they are, essentially letting you trial orbital-transfers without spending a single ounze of fuel, until you get it just right.

Once in steady Kerbin orbit, left-click a point on your flightpath, click the button that pops up, and just mess around with the settings (coloured markers that pop up around the node). Best to do that for a good 10 minutes, just get a feel for what it does, and you can delete it at any time by left-clicking the centre-circle again and pressing the red cross.

Obviously this isn't autopilot, so don't drift past a node and wonder why nothing happened, like I did for a the first half-dozen times I set one up!

##### Share on other sites

2. Set target, adjust relative inclination to zero at AN/DN

Actually, you save a nice amount of delta V by doing your plane change halfway to Minmus. Changing your inclination near to Kerbin takes a bunch of fuel.

##### Share on other sites

Rats I type too slow...

1) Once you're in Kerbin orbit make Minmus your target.

2) There will be 2 markers that show your inclination. Place a Maneuver Node at one of them.

3) If it's "Ascending" you will want to drag the bottom pointer down until the 2 inclination markers are approx 90Ã‚Â° from the starting position. If its "Descending" drag the top pointer the same.

4) Rotate your ship to either 0Ã‚Â° or 180Ã‚Â° (wherever the blue heading marker is located).

5) Look at your "Total Burn Time" and start your burn at 1/2 the time of your arrival to the Maneuver Node. That is if it's 2 minutes, start your burn at 1 minute before you arrive.

6) Watch the inclination markers and stop burning when they reach near 0Ã‚Â° (anything outside of Kerbin SOI should be more precise). Your ship's orbital plane should now match up with Minmus. Delete the Maneuver Node.

7) Now you will want to set another Maneuver Node anywhere from 90 ~ 135Ã‚Â° behind Minmus.

8) Drag the Prograde pointer until you have an intercept with Minmus. Fine tune it until Minmus Periapsis is around 6,000~20,000m. With airless planets, in genera,l it's easier to capture an orbit the closer you are to the surface.

Aeshi did a chart for minumum safe orbits. Check my post here: -Question-Capturing-Orbits-Is-there-an-Optimal-Altitude-for-Airless-Planets Props to Scintillator for directing me to the answer and Aeshi for the chart.

9) Time Warp to just prior to Minmus SOI. Note: Don't ever "Timewarp" faster than 2x when crossing SOI boundary markers. It will throw off your periapsis quite alot.

10) When you are in Minmus SOI place a Maneuver Node at your periapsis and drag the pointer until you have an orbit. I usually set mine around 60,000m but I have gone as low as 6,000~8,000m.

11) As before start firing, "Retrograde" this time, at 1/2 the time of your total burn time to your arrival to Maneuver Node until you've closed your orbit. Keep an eye on your Periapsis. Don't let it drop below 6,000m. Set your Apoapsis to your liking.

12) When you reach Apoapsis fire your rockets "Prograde to raise your Periapsis and you have an orbit.

For other transfer orbit calculations see: Tranfer Orbit Calculator

Edited by Landge
##### Share on other sites

2) There will be 2 markers that show your inclination. Place a Maneuver Node at one of them.

3) If it's "Ascending" you will want to drag the bottom pointer down until the 2 inclination markers are approx 90Ã‚Â° from the starting position. If its "Descending" drag the top pointer the same.

4) Rotate your ship to either 0Ã‚Â° or 180Ã‚Â° (wherever the blue heading marker is located).

5) Look at your "Total Burn Time" and start your burn at 1/2 the time of your arrival to the Maneuver Node. That is if it's 2 minutes, start your burn at 1 minute before you arrive.

6) Watch the inclination markers and stop burning when they reach near 0Ã‚Â° (anything outside of Kerbin SOI should be more precise). Your ship's orbital plane should now match up with Minmus. Delete the Maneuver Node.

I'll say it once again, but it's much, much more efficient to do your plane change halfway through to Minmus than before doing the transfer burn.

##### Share on other sites

I'll say it once again, but it's much, much more efficient to do your plane change halfway through to Minmus than before doing the transfer burn.

Sorry I was typing and missed your post! Thanks, that will save me a ton on fuel!

##### Share on other sites

One alternative that I haven't tried yet is to launch directly into the plane of Minmus. To do this, you set Minmus as your target while on the launch pad, and wait until the ascending or descending node is right above the launch complex. Then, launch. If the node is ascending, you want to be slightly north of east, by 6 degrees (the inclination of Minmus' orbit). If it's a descending node, you wand to be 6 degrees south of zero inclination. If you can get it close enough this will really save on plane change corrections later.

The problem people have with doing the plane change after the transfer burn is that the transfer burn itself won't give you an intercept, and without mods, it can be tricky to tell if Minmus will actually be at that spot after you do the burn. The stock game gives you surprisingly little information. Even if I do my launches manually, I'd still like to have MechJeb's info displays so I can see my apoapsis and inclination real time during the launch.

##### Share on other sites

I'll say it once again, but it's much, much more efficient to do your plane change halfway through to Minmus than before doing the transfer burn.

more efficient maybe, but not as easy. Of course launching into plane for Minmus from KSC is even more efficient, so launch into a 6 degree inclination.

##### Share on other sites

more efficient maybe, but not as easy. Of course launching into plane for Minmus from KSC is even more efficient, so launch into a 6 degree inclination.

Bah, it's as easy as adding a maneuver node halfway and doing a small axial tilt, it's not too complex.

##### Share on other sites

I'll say it once again, but it's much, much more efficient to do your plane change halfway through to Minmus than before doing the transfer burn.

Actually plane changes are most efficient when you're furthest from the primary body (Kerbin, in this case.) This is due to simple inertia; it's easier to change the direction of a slow moving object than a fast moving one, and you're slowest at apoapsis. The trouble in this discussion is that we're talking about two kinds of intercept:

1) If you want to have your whole orbit in Minmas's orbital plane (6 degrees inclined relative to Kerbin's equator), you have to adjust at the AN or DN, which are both going to be near Kerbin. This kind of orbit is much more forgiving; you can push your apoapsis out past Minmas's orbit and get two possible intercepts; and the map view will show them more readily.

2) If you adjust mid flight, you're going for a single point intercept, where your orbit intercepts Minmas's orbit only at a single point; hopefully when Minmas is there. This is probably more efficient than 1, but can result in highly inclined final orbits around Minmas, and is more difficult to pull off. And you'll probably have higher relative velocities at intercept, which means your capture burn will be longer.

##### Share on other sites

Actually plane changes are most efficient when you're furthest from the primary body (Kerbin, in this case.) This is due to simple inertia; it's easier to change the direction of a slow moving object than a fast moving one, and you're slowest at apoapsis. The trouble in this discussion is that we're talking about two kinds of intercept:

1) If you want to have your whole orbit in Minmas's orbital plane (6 degrees inclined relative to Kerbin's equator), you have to adjust at the AN or DN, which are both going to be near Kerbin. This kind of orbit is much more forgiving; you can push your apoapsis out past Minmas's orbit and get two possible intercepts; and the map view will show them more readily.

2) If you adjust mid flight, you're going for a single point intercept, where your orbit intercepts Minmas's orbit only at a single point; hopefully when Minmas is there. This is probably more efficient than 1, but can result in highly inclined final orbits around Minmas, and is more difficult to pull off. And you'll probably have higher relative velocities at intercept, which means your capture burn will be longer.

I did the math once, and I came out by using less delta V by doing the plane change halfway, then leaving my apoapsis higher during my capture burn, doing my plane change far away from Minmus (that already has a very small gravitational well anyway) and then by doing my circularization burn in low Minmus orbit. But coming in and landing from the slightly inclined orbit isn't much of an hassle anyway.

##### Share on other sites

I got the same answer when I ran the numbers awhile back. a plane-change to reach minmus at about 30,000 km tended to max out at about 85 m/s, and was generally significantly cheaper.

And besides, all the cool kids use CONIC_PATCH_DRAW_MODE = 0 in the settings.cfg, which makes it easy to see exactly what your path will be around Minmus when you get there, and lets you tweak it effectively with maneuver nodes far outside the SOI.

All told, if you're already in orbit, it probably would be cheapest to combine your plane change and the transfer burn into a single burn, but KSP isn't very accommodating for that sort of thing.

##### Share on other sites

I did the math once, and I came out by using less delta V by doing the plane change halfway, then leaving my apoapsis higher during my capture burn, doing my plane change far away from Minmus (that already has a very small gravitational well anyway) and then by doing my circularization burn in low Minmus orbit. But coming in and landing from the slightly inclined orbit isn't much of an hassle anyway.

It's generally most efficient not to try to match the inclination of your target during the transfer, but just to make your transfer orbit intersect the target orbit at the right time. Two ways of doing that are to include an inclination change component in your ejection burn (where you get to take advantage of the law of cosines which can reduce a 30m/s inclination change down to about 0.5m/s net) or to change your inclination mid-transfer like you're suggesting. The optimal point to do the inclination change mid-transfer varies depending on the eccentricity of your transfer orbit and the angle by which you need to change your inclination.

I hacked my porkchop plotter a bit to explore the transfer to Minmus from a 100km Kerbin orbit and it looks like the two strategies are pretty much equivalent in terms of delta-v (about 1410m/s total depending on the window), but the window is much larger for the mid-course plane change strategy. The optimal time to do the plane change maneuver varied but was generally quite close to Minmus (around 5 degrees prior to intercept, for example).

I think the simplest and most efficient transfer to Minmus would be to wait for a window where Minmus will intersects an ascending/descending node at the time of intercept. Then you don't have to do any plane change and you can get an intercept with a single maneuver node.

## Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

×   Pasted as rich text.   Paste as plain text instead

Only 75 emoji are allowed.

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×

• #### Community

• Release Notes

• #### Social Media

• Store
×
• Create New...