How to get a perfectly equatorial orbit around moons in the stock game??

[Dafni]

Hey crew, the title says it all. How to get an accurate number for the inclination, or how to get the DN/AN when you are in orbit around a moon (i.e. cant set an orbiting body with zero inclination as target)???

For example, around Kerbin we can use the Mun as target and get AN/DN to make corrections to get a perfectly equatorial orbit, but I have yet to find a way to do this around the Mun.

Am I missing something?

 

Thank you in advance

Daf

[Magzimum]

You will need KER. That's a mod that gives information, but does not fly your ships or actually do anything at all. (And in my opinion, it should be stock). 

If you look at the various tabs, enable the one called "Surface". That shows your latitude and longitude. When the latitude will approach zero (i.e. you're about to pass the equator), you are at the AN/DN.

The inclination itself is listed under "Orbital", also in KER.

[Streetwind]

In stock KSP? You can eyeball it to get very close by using the navball. If you orientate your ship the right way, you can use the horizon line to see where you cross the equator, and then make repeated small burns in those places to try and make your prograde vector stick as close as possible to the horizon.

With mods? MechJeb or KER or similar mods will display your current inclination, as well as where your orbit crosses the equator.

[Dafni]

3 hours ago, Magzimum said:

You will need KER. That's a mod that gives information, but does not fly your ships or actually do anything at all. (And in my opinion, it should be stock). 

If you look at the various tabs, enable the one called "Surface". That shows your latitude and longitude. When the latitude will approach zero (i.e. you're about to pass the equator), you are at the AN/DN.

The inclination itself is listed under "Orbital", also in KER.

 

3 hours ago, Streetwind said:

In stock KSP? You can eyeball it to get very close by using the navball. If you orientate your ship the right way, you can use the horizon line to see where you cross the equator, and then make repeated small burns in those places to try and make your prograde vector stick as close as possible to the horizon.

With mods? MechJeb or KER or similar mods will display your current inclination, as well as where your orbit crosses the equator.

 

Thank you guys. That's what I was afraid of. I know about the mod solutions, and I used them before, as well as the eyeball approach that stock offers... I was just checking if I missed a better option in stock KSP.

I agree that the inclination information should be a stock feature, as well as some other useful (not to say essential) numbers that KER or MJ provide.

 

Thanks again

Daf

[Superfluous J]

It's important to note that while you can't get the information in the stock game, you also have no reason to need it. 1 degree off of equatorial is just as good as equatorial for all stock implementations, because you're dealing with nonnumeric maneuver nodes and imperfect trajectories.

Even with KER installed, there's no real reason to need a perfectly equatorial orbit.

[Dafni]

48 minutes ago, 5thHorseman said:

It's important to note that while you can't get the information in the stock game, you also have no reason to need it. 1 degree off of equatorial is just as good as equatorial for all stock implementations, because you're dealing with nonnumeric maneuver nodes and imperfect trajectories.

Even with KER installed, there's no real reason to need a perfectly equatorial orbit.

True indeed. Call it a mix between OCD and the quest for the most efficient lunar orbit rendez-vous, Apollo style. I like to launch my lightweight LEM ascent module straight to the rendez-vous with the Command Module (CM) and naturally I have some inconsistencies with fuel consumption (the longer you stay on the surface the more you have to adjust your ascent profile when the AN/DN of the CM is slowly drifting away from you. Difference is especially notable in very low CM parking orbits). Its minor and not much of a problem really, I was just looking for ways to make it more "perfect". But yeah, you are absolutely right of course.

Edited February 24, 2017 by Dafni

[TheKorbinjer]

Launch yourself into an orbit, with a spacecraft with the capability of making maneuvers in orbit, set the mun as a target, and it'll tell you your relative inclination. Make burns until it says 'NaN'*

 

I do believe there's a place in the cheat menu that will tell you extreme specifics (down to the ten thousandth of a degree(relative to the equator))

It's under physics tab. Enable "GUI"s where possible.

[Streetwind]

15 minutes ago, TheKorbinger said:

Launch yourself into an orbit, with a spacecraft with the capability of making maneuvers in orbit, set the mun as a target, and it'll tell you your relative inclination. Make burns until it says 'NaN'*

 

I do believe there's a place in the cheat menu that will tell you extreme specifics (down to the ten thousandth of a degree(relative to the equator))

It's under physics tab. Enable "GUI"s where possible.

...You might want to read his opening post. Just a suggestion.

However, the thing with the debug menu? That's interesting, I never heard of that. Will have to see if I can find it once I get home.

[Dafni]

Thank you @Streetwind

 

The thing with the debug menu is new for me too, might be just what I was looking for. Cheers @TheKorbinger

[TheKorbinjer]

1 hour ago, Streetwind said:

...You might want to read his opening post. Just a suggestion.

However, the thing with the debug menu? That's interesting, I never heard of that. Will have to see if I can find it once I get home.

Whoops. I seem to do that alot. =/

[Tyko]

here's a stock solution that's only slightly cheaty - use the F12 menu to put a reference object in orbit around the target body. Call it a navigation beacon or some such. The orbit command places the object in a perfectly circular orbit with zero degree inclination

Edited February 24, 2017 by Tyko

[paulprogart]

2 hours ago, Tyko said:

here's a stock solution that's only slightly cheaty - use the F12 menu to put a reference object in orbit around the target body. Call it a navigation beacon or some such. The orbit command places the object in a perfectly circular orbit with zero degree inclination

Similar but less cheaty is if you have a derelict from a basic rescue or have done a satellite with a basic orbit at the target body, then you can use one of those as a reference because they will be at almost exactly 0 degrees.  (There will be a small margin of error due to either the EVA exit or the satellite tolerance.)

Problem there of course is that it's a very big "if" depending on your career progression.  (If you're even in career mode... if not then please ignore.)

Edited February 24, 2017 by paulprogart
didn't see career mode mentioned... oops

[bewing]

8 hours ago, Streetwind said:

...You might want to read his opening post. Just a suggestion.

However, the thing with the debug menu? That's interesting, I never heard of that. Will have to see if I can find it once I get home.

If you get your inclination to NaN before you get to the Mun, then it will still be NaN once you are at the Mun -- because it's all coplanar, and your retrograde hold does a good job of keeping it there. And in that way, you can leave a little piece of debris (a stage separator maybe) in that perfect equatorial orbit, and use it as a reference.

 

[Tyko]

9 hours ago, Dafni said:

True indeed. Call it a mix between OCD and the quest for the most efficient lunar orbit rendez-vous, Apollo style. I like to launch my lightweight LEM ascent module straight to the rendez-vous with the Command Module (CM) and naturally I have some inconsistencies with fuel consumption (the longer you stay on the surface the more you have to adjust your ascent profile when the AN/DN of the CM is slowly drifting away from you. Difference is especially notable in very low CM parking orbits). Its minor and not much of a problem really, I was just looking for ways to make it more "perfect". But yeah, you are absolutely right of course.

If you're shooting for Apollo level accuracy you can do pretty well with just the mk1 eyeball and stock tools. They certainly didn't have .001 precision on their maneuvers either. They also didn't have the benefit of maneuver nodes.

[Superfluous J]

Also important to note, Apollo didn't orbit the Moon's equator, partially because the Moon doesn't orbit directly over ours, and partially because it didn't matter to them, either

[Tyko]

Talking about accuracy. I didn't realize that Apollo 12's lander - Intrepid - was able to land within 70 meters of the Surveyor 3 probe. I've been practicing landings for a year now and I can finally get within a few hundred meters. Apollo did it on their second moon landing.

https://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/lroc_20090903_apollo12.html

Edited February 24, 2017 by Tyko

[Dafni]

9 hours ago, 5thHorseman said:

Also important to note, Apollo didn't orbit the Moon's equator, partially because the Moon doesn't orbit directly over ours, and partially because it didn't matter to them, either

Point taken 

[cratercracker]

Maybe it sounds hard but here is a sollution of Finding perfect equatorial orbit:

Okay,okay lets start!

1)Land a lander/rover near the equator.

2)Drive/land to a strange line( It is some sort of line with no texture right in the middle of any planet!)

3) Git into orbit around planet/moon you want

4)Set your lander/rover as a target

5) In orbital view you can see inclination difference with your rover/lander

4)hopefully legit

[FancyMouse]

Why nobody mentions Kerbnet? The ability of telling you latitude is as good as telling you the exact numbers (despite some manual calculation needed, and you may need to travel multiple orbits to get info/do burns). Roughly the steps are:

1. Find your maximum latitude. Derive inclination from that.

2. Find AN/DN by monitoring the latitude until you get to equator. Compute your orbital velocity from your altitude at that moment (along with other orbital parameters).

3. Compute the necessary delta V, plot maneuver and burn (either plot at the same AN/DN you get from previous step and burn after a orbital period, or just bravely burn immediately).

Repeat until you're happy with the precision.

[Blaarkies]

Use the stars!

It's much easier than IRL because KSP has no axial tilt. You need a rover landed on the moon, then lookup at the same star for 4 kerbin years(this will give a nice average). Use the sundial method to draw lines indicating where the star was last year...if you see that the stars at it's peak does not have an azimuth of Pi/2, then move your rover(in the stars general direction...relative to the ground of course)

Rinse and repeat, then some 20 Kerbin years later you should have the perfect, up to the closest eyeballing unit of measure accuracy in where the equator is.

Glad i could help!

[Superfluous J]

5 hours ago, FancyMouse said:

Why nobody mentions Kerbnet?

I actually didn't know Kerbnet told you your current lat/long. That's convenient. Of course, it'd be the lat/long of when you took the "screenshot" but for all but the lowest orbits on the biggest worlds will you get far enough from that quickly enough for it to matter.

17 minutes ago, Blaarkies said:

Use the stars!

I've done this, only with the galactic equator which happens to match every planet's equator. It gives a nice "close enough for me" equatorial orbit.

Edited February 28, 2017 by 5thHorseman