Basic Basic help with the Moon

[MrFoo]

Ok here goes, I am a noob, I have been playing the Orbiter Simulator for little over a month now, I have managed to fly nearly anything into orbit, I havent tried docking with the ISS or MIR.

Anyway, my biggest goal at this time is to reach the moon and return to earth. But I just can't do it, I have tried every manual going, from Learn to Play in space to IMFD to the moon for dummies, no-one explains it in the clearest basic terms possible. All the guides assume you know what its talking about.

Now I do appreciate Orbiter has a steep learning curve, and I am not the quickest of learners, but I am slowly getting there.

What I really would like, is you nice people to help in the basic way possible, like in earth orbit do I align orbits with the moon first? if so then do I use Transfer MFD? or do you think IMFD is the way? I barely know how to use Transfer MFD, but not a clue with IMFD. I dont know what ECC is, or PeA.

I have managed to blast out of earth orbit using Transfer MFD but my biggest issue is, when do I peform MCC? I mean what do I look out for to know I need one?

I am prob not making any sense, but can anyone help, is there a basic guide for noobies to get to the moon and back, without assuming you know complicated terms or procedures?

Sorry if this has been asked many times before, but maybe you could sticky this, so its there for all to see?

Thanks for your time.

 

[TSPenguin]

I dont know what ECC is, or PeA.

I am sorry, but without the essential terminology, you are pretty lost. Check orbiterwiki, it has nice explanations for everything.
I'd also recommend learning docking first. It is an essentiel operation and the deployed methods also apply to interplanetary travel. I recommend Orbital Operations to learn.

Going to the moon with transferMFD is quite easy, especialy if you watch the included replay that comes with orbiter. But understanding orbital mechanics first is pretty essential.

 

[ripley1]

As the TsPenguin said,its essential to learn few things before the interplanetary flight.But if you really want to,check out this thread.It includes Transfer MFD video tutorial.
http://www.orbiter-forum.com/showthread.php?t=7859

 

[insanity]

There are a lot of tutorials on this website- either written of the forums or linked. I'd watch the tutorial video in Orbiter reread the first part of Go Play in Space and then try their method yourself. Asking questions when you have no idea about the terms or concepts used in the answer will not help you figure out what you need to do.

 

[MrFoo]

Ok sorry if I am pissing people off with my noobness lol.

I can assure you I am reading everything I can and re-reading it, trying it out etc.

Thanks for you help anyway guys or gals.

 

[Hielor]

The default Orbiter installation has a playback of a flight to the moon. Watch that.

 

[ex-orbinaut]

I have noticed previously that a frequently overlooked and excellent resource for basic information on terminology and certain operations is the Orbiter.pdf manual, located in the Doc folder of the Orbiter installation. Lots of relevant information in chapters 13, especialy section 13.2 for what you were asking about Pea and such. Alignment and synchronization info in 13.8 and 13.9. Docking in 16.7. Good luck.

PS: Almost forgot; also these two, recommended on the very Orbiter download page, are really good for helping with the acquisition of basic knowledge;

http://www2.jpl.nasa.gov/basics/index.php
http://www.braeunig.us/space/index.htm

 

[Sam]

> I have managed to fly nearly anything into orbit, I havent tried docking with the ISS or MIR.

That should be your next step. At least rendezvous with one of those two (get to within about 1km, with <1 m/s relative velocity). Start from a lower orbit, then use Align Planes and Transfer MFDs to get you there. That way, the methods you use will be similar to how to get to the Moon.

As long as you're there, you might as well have a go at docking, although that isn't really helpful as "Moon training."

> in earth orbit do I align orbits with the moon first? if so then do I use Transfer MFD? or do you think IMFD is the way? I barely know how to use Transfer MFD, but not a clue with IMFD. I dont know what ECC is, or PeA.

That's how I do it (align planes, then Transfer MFD), and I've never had any trouble that way. I don't know jack about IMFD. I'm pretty good with TransX, but frankly I think that's overkill if you just wanna go to the Moon, and it's too much too fast for a newbie.

> when do I peform MCC? I mean what do I look out for to know I need one?

If you just want to land anywhere on the Moon, in other words you're not shooting for a particular landing point, the only thing you really need to worry about is the aforementioned PeA, which is periapse altitude. That means how far above ground you are at your closest approach, so be sure that doesn't end up being negative. If it does, you'll have a very hard landing.

Do MCCs when you get close enough to the Moon for the Orbit MFD numbers to start making sense when REF=Moon. I usually start watching the numbers closely when I'm about 50,000 km away from the Moon. The numbers will continue to drift until you're pretty close in, so just do a rough estimate at first, then you can do additional MCCs when you get closer to fine tune things. For example, if I see that PeA is drifitng upward, I'll MCC to push it back to ground level at first. By the time I'm closer in, it will have drifted up again, and I'll fine tune it to where I want it to be.

Once you're at lunar periapse, retro burn into a circular orbit, then land from there. Now, getting back from the Moon is a little more complicated...

SAM

 

[Tommy]

Actually, getting back from the moon is fairly easy if you aren't too concerned about doing it in the absolute most efficient way. Get into a Moon orbit with a very low Inclination (how much above and below the Moon's equator you go). Wait until the Earth "rises" above the horizon, and let it get a bit above the horizon. One "Earth width" is good. Then burn Prograde until OrbitMFD shows you will escape the Moon (Ecc >= 1, when the orbit "snaps" open). Then change OrbitMFD's reference to Earth. watch the number on the bottom, and when it changes from red to yellow then green, (you are in the Earth's Sphere of Influence) you can burn Prograde to raise your PeA, or Retrograde to lower it. It's crude, but it works.

 

[ar81]

Reaching the moon is somehow similar as reaching ISS.
Both bodies orbith Earth.
You should learn to reach ISS first.
[ame="http://www.orbithangar.com/searchid.php?ID=3074"]Tutorial: DG to ISS[/ame]

Then you may need to learn about interplanetary flight, since reaching Moon is slightly different
[ame="http://www.orbithangar.com/searchid.php?ID=3403"]Tutorial: Concepts for Interplanetary MFD 4.2.1[/ame]

 

[Matt Decker]

I find the easiest way to get to the Moon is use IMFD5.2. It is best to be aligned with the Moon but you don't have to be.

Just click MNU, then select Course. Highlight, "Target Intercept", and click on "Set". It will tell you to select a target. Click on "TGT", and type in Moon.

Then click on "Nxt" until "Realtime" is highlighted. Change that to "off-axis" by clicking on the "+" right below the "Nxt" button.

Then click on "PG" (one of the things about the IMFD is that you need to understand how hitting "PG" changes the display),

Then click on "AB" and wait for burn time.

:focus:

 

[ar81]

If you do not align with moon, you are having an off plane transfer.

 

[MrFoo]

Thanks for all the advice guys.

Been reading about Ecc, lol you need a PhD just to understand that alone lol

 

[n122vu]

Thanks for all the advice guys.

Been reading about Ecc, lol you need a PhD just to understand that alone lol

We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard... John F. Kennedy, 1962

The reason rocket science is used as the difficulty benchmark for other tasks, is because it is rocket science...

 

[Tommy]

Been reading about Ecc, lol you need a PhD just to understand that alone

I have found that we are often given more information than we really need. You don't actually need to fully understand the math and physics of eccentricity unless you are performing a flight much more complex than a simple Moon trip. For most purposes it's enough to understand that Ecc =0 means a perfect circle. Ecc greater than 0, but less than 1 means an elongated, less "round", orbit, and Ecc of 1 or more means you will escape the planet/moon you are orbiting. It does help to know how to adjust your Periapsis (the lowest point of your Orbit) and your Apoapsis (the highest point). The closer they are to matching, the lower your Ecc will be.

Practice adjusting your Orbit while in LEO (low Earth Orbit), and once you can comfortably and reliably adjust your Pe and Ap (and therefore your Ecc) you'll be ready for the next step.

For most things, it's not absolutely necessary to completely understand the physics and math involved, and it's easy to overwhelmed by too much information that just confuses even more. However, in order for anyone to be able to help you it is essential that you have a basic understanding of the terms and techniques. Just imagine trying to talk someone through making a sandwich when they don't understand what you mean by "bread", "knife", or "Butter". They don't need to know how bread is made, or what it's ingredients are, but they do need to know that "bread" means the brown loaf on the counter. They should also know the basics of how to use a knife (hold it by the handle and cut with the sharp side, etc.)

 

[MrFoo]

Thank you Tommy, I thought that was excellent advice, I was getting to the point of just not attempting orbiter anymore, because I thought I don't have the 'know how', but that post inspired me to keep trying.

Thank you

 

[Tommy]

Any time. I can't remember how many tries it took me to get into orbit the first time, or dock the first time, etc. Often reading the tutorials didn't really make sense at first, but if you keep trying, eventually it will start to click. Start simple, and let it come to you. You don't need to know the physics behind the reason burning prograde raise the opposite side of your orbit, it's enough to know that it happens. As you use the techniques of spaceflight, and experiment, understanding of the physics will come in time.

 

[TSPenguin]

Any time. I can't remember how many tries it took me to get into orbit the first time, or dock the first time, etc. Often reading the tutorials didn't really make sense at first, but if you keep trying, eventually it will start to click. Start simple, and let it come to you. You don't need to know the physics behind the reason burning prograde raise the opposite side of your orbit, it's enough to know that it happens. As you use the techniques of spaceflight, and experiment, understanding of the physics will come in time.

That is exactly why I love orbiter so much.
You have to understand a little to perform various maneuvers, but that is often the reason to research further, learn more.

 

[Sam]

Actually, getting back from the moon is fairly easy if you aren't too concerned about doing it in the absolute most efficient way.

Point well taken. I prefer a more precise approach, but this is advice for a first-timer to get there and back.

SAM