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[BigD145]

It'll get science you can use to get more scientific instruments and make landing on either body more lucrative in a single mission.

[WillowLuman]

If you want to get to Minmus, go for a Mun encounter. More often then not, a Mun encounter can give you a big boost outwards that will greatly save on fuel.

Also, as said before, an even easier way to get lots of science is to get flung outside the Kerbin system into solar orbit, then return. Takes a wile, though, so while waiting to re-encounter Kerbin you may as well do other missions.

[GreatWyrmGold]

If you want to get to Minmus, go for a Mun encounter. More often then not, a Mun encounter can give you a big boost outwards that will greatly save on fuel.

Huh? How would I perform this, exactly?

[BigD145]

Also, as said before, an even easier way to get lots of science is to get flung outside the Kerbin system into solar orbit, then return. Takes a wile, though, so while waiting to re-encounter Kerbin you may as well do other missions.

You can burn a little to slow down and fall back to Kerbin SOI.

[Aseaheru]

If you want to get to Minmus, go for a Mun encounter. More often then not, a Mun encounter can give you a big boost outwards that will greatly save on fuel.

Huh? How would I perform this, exactly?

Manuver nodes.

They are your friend.

[WillowLuman]

If you want to get to Minmus, go for a Mun encounter. More often then not, a Mun encounter can give you a big boost outwards that will greatly save on fuel.

Huh? How would I perform this, exactly?

Make your trajectory intersect the Mun's. From the camera view where the Mun's plane of orbit looks top-down (and the Mun is travelling "clockwise"), your intersect should be about 15 degrees ahead of where the Mun currently is. Once you have an encounter, it will show with your blue orbit path leading into an orange one, which leads into a purple one. The purple is the trajectory you will be on after the encounter. If you want, you can burn retrograde during the orange path to become captured by the Mun, but you won't want to do this if your target is Minmus.

[GreatWyrmGold]

And how do I make sure this helps me reach Minmus rather than sending me careening out of Kerbin's SOI and into interplanetary space?

[WillowLuman]

Like at any other time, you can adjust your trajectory by burning in various directions. Use a maneuver node to see how much to burn without going too far. If you burn too much, you'll probably overshoot and not encounter the Mun.

[GreatWyrmGold]

And how does this help me reach Minmus? How do I make sure that bouncing off of Mun gives me an acceleration in the right direction?

[WillowLuman]

Have you done the Mun orbit tutorials in Scenarios?

It's just how Orbits work. Direction isn't really an issue. Any acceleration gives you a higher Apoapsis. If your apoapsis is far enough, it will intersect Minmus's orbit. If it intersects close enough, it's just a matter of waiting for an encounter. Slingshotting from Munar orbit gives you a lot of acceleration that you don't need to spend fuel on. If your trajectory will fling you out of the system, adjust it until it won't.

[GreatWyrmGold]

Have you done the Mun orbit tutorials in Scenarios?

I haven't really looked at the Scenarios.

It's just how Orbits work. Direction isn't really an issue. Any acceleration gives you a higher Apoapsis. If your apoapsis is far enough, it will intersect Minmus's orbit. If it intersects close enough, it's just a matter of waiting for an encounter. Slingshotting from Munar orbit gives you a lot of acceleration that you don't need to spend fuel on. If your trajectory will fling you out of the system, adjust it until it won't.

It strikes me that, unless your orbit is pretty well circular, you'd have to hit it pretty accurately.

[Aseaheru]

SANARIOS. PLAY THEM NOW.

[WillowLuman]

The only thing a circular orbit is good for is rendezvous and observation. A circular orbit actually makes encounters harder, because you have to loose more energy once you're near the target body in order to remain in its orbit. If you circularize your orbit once it intersects the object, you'll just wind up co-orbiting it (sharing the same path but at a different point).

Say you get a Munar encounter where your periapsis is at about 80,000m. Once you are in the orange (where you're within the Mun's SOI) part of the orbit, you need to burn retrograde (decelerate) so that you loose the velocity which would carry you out of the Mun's SOI. If your periapsis was much higher (approaching a circular orbit), you'd need to burn much more, possibly spending all your fuel, and the burn would possibly be so long that you pass out of Munar orbit before you can complete it.

SANARIOS. PLAY THEM NOW.

Probably a good idea. Will save much tears and trial-and-error

[GreatWyrmGold]

I'm still confused about how to use munar encounters without the Mun and Minmus being in the right places, but let's do the scenarios!


Scenario 1: EVA in Kerbin Orbit

"Jebediah Kerman on EVA about 40 meters from his ship."

...Please be misnamed tutorials.


_...Crap.

And when I hit the 'r' key, Jeb won't re-orient himself to face the camera, which makes it hard to aim him.
I try to follow the capsule but fail. I keep trying, but lose sight of the capsule, even with it set as target.


_{This all seems, in the end, futile.}

I reload, wanting to start over.


_{That is NOT 40 meters.}

I blast straight towards it, or as close as I can. It continues to fall away, getting almost a kilometer off before I start catching up. I keep struggling to close the distance.


_{Come on...come on...}

It gets a bit closer than 200 meters before somersaulting away.
...Remind me to put ladders on anything I want to EVA with in space.

I line up another good burn, not letting it get even 800 meters off before the distance starts dropping. We manage to get within 90 meters before it starts zooming away again.

...Screw this, I can't even get a bead on the thing. The controls suck, and I have no clue what to do. What's the next scenario?


Scenario 2: Impending Impact

"The Mun 7flyby spacecraft is heading straight for an impact with the Mun! See if you can avoid a catastrophe and get Jebediah back home!"


<sub>Dark.

I guess it's technically an encounter...

What's this big yellow--oh. Now that's neat.

Very neat.

So with a periapsis in eight days and an apoapsis in 66, we would have an orbit of 2(66-8)=wait, I'm getting off-track here.

Not ideal, but...that'll do, pig.</sub>

Right. Mun. Kerbin. Jeb. We've got the node, let's time-accelerate some.


_{And also burn a tad in a random direction for an estimate of burn time. Four minutes 21 seconds, it says.}

Ah. Relaxing. And it plays to my strengths: Not rendezvousing.


<sub>It wasn't that funny, Jeb. Shut up. I said shut it. QUIET! Don't make me crash you into Kerbin without a space suit!


It's getting close, and closer by about a kilometer every three or four seconds.

And it's time.

...seems it will be for a while. Well, let's just watch the Mun go by.

Let's hope the node was right, eh?

There's a lot of lines here, but...I think we're now going to not hit the Mun and we're going into Kerbin orbit?

Oh. That looks bad. Better kill the engine.</sub>

There needs to be a way to tell if you'll have any fuel left in your tank after the maneuver is done...
Anyways! Let's see how this works, for now. At our Kerbal Periapsis a few hours from now, we'll try burning retrograde and hopefully end up...


_...alive.

...there, brushing Kerbin's atmosphere.
But let's just wait a while.


_{Not too long. Where's the time-accelerate button?}

Right about at 5:55:00, we reach the megameter mark. Even with zero time-acceleration, we're seeing the numbers whir by, since we're going over 550 m/s relative to the Mun.


<sub>It's growing larger...disturbingly large...how close are we supposed to get again?

I really, really hope we're going fast enough and far enough.

"(muttered prayers to KHWH)"

We're still going to crash, aren't we?

Yup. Carp.</sub>

The maneuver nodes lied to us! The lying liars!

We're at about 20 kilometers and seem to be falling about a kilometer every other second. Maybe a bit faster. We have 1.33 units of fuel, which need to stretch over some unit of the ~30-40 seconds before we land. Maybe we should wait until there's ~15-20 seconds left, then burn at a rate of 0.08-0.09 units per second. That sounds good.
Oh Kod. Oh Karp.


<sub>You lied! And I suppose I didn't have much chance of slowing down in time anyways.

That was...fun.</sub>


Scenario 3: Mun Orbit

"The Kerbal 11 Mission in low Mun Orbit. This mission is comprised of two docked vehicles, the Landing Module and the Command Module. The lander is undocked from the Command Module, flies down to land, then returns to orbit where the Command Module will rendezvous and dock with it. After that, the lander is discarded and the crew leaves Mun orbit to return home."

I like my plan better.


<sub>Space is pretty.

Well, no reason to dawdle, eh?

Why is everything drifting now? Let's try switching.

Um...?

Oh, I see! ...I wonder why the lander has a parachute.

Here comes the tricky part...landing.

Preceded, of course, by managing to get into a crashing course.

Here we go!

...in, oh, about twelve minutes' time.</sub>

And so the landing is getting prepared.


<sub>Maybe that line was just an excuse to break up a series of pictures. So what?

Wait, are those landing struts on the...shit, this is the command module isn't it?

Crew reaction is...shall we say...mixed.</sub>

I start the burn at the guessed time, only to discover that the engine is off and, relatedly, the estimated burn time was way off. Current periapsis: 10,625 meters. Not quite close enough for landing, neh? I plan a maneuver to bring it down to 4,888.
We wait for the node, watching the real lander drift away all the more, wondering how we were supposed to get over there anyways. A few seconds beforehand, I burn, finishing it faster than I had imagined. Our periapsis is 4,523 meters, which works.

One nice thing about atmosphereless bodies is that it's easier to predict where you'll fall. I add a maneuver node to just about kill the last of our orbit and end up pretty close to the surface.


_{Because landing the command module wasn't death-defying enough on its own?}

That orbit has us landing here:


_{Looks safe enough. Light, at least.}

And so we say goodbye to Mr. Sun until after the Node.


<sub>Also, Bob suspects that Bill is an alien spy.

Trust me, that crater looked REALLY cool a couple seconds before I took the picture.

Getting pretty close...

Dammit, dot, why don't you like focusing right on the right spot?

Man, this just doesn't feel right, you know?</sub>

Then something happens. There's an explodey sound and we start spinning.


<sub>Hey, guys, what happened? ...Guys?

What the hell did you guys do? We're reading an apoapsis of over a hundred forty-five kilometers! You've wasted Kord* knows how much delta-v, and landing way far from our planned landing point. ...Guys?</sub>

*Kord: God of Strength and War. Chaotic Good.

Well, that went poorly. And that seems to be a docking port, by the way. Sadly, it wasn't giving me the catastrophic failure log, so I didn't learn the sequence of events that lead to one little docking port being sent into where the Mun's stratosphere would be if it had any air. Still, I got to watch what happened as the docking port sailed through the lack of air and into the Munar surface.


<sub>Ooh. Kerbrise.

More bits of debris, too far to guess what they are. At least ten are still around, although all are lower than the docking port.

A new kind of sunrise.

More or less the peak of the orbit.

I could probably see my house from here, if I lived on this section of the Mun.

Oh hey, we're a docking port attached to a battery, that changes everything!

"Well, you're getting close to the surface so um...happy landing? Good luck?"

Getting pretty close...

Dammit! A second too soon!

"We're calling this one a catastrophic failure."</sub>


Scenario 4: Station One

"Space Station 1 is a small refueling outpost at low Kerbin orbit, where ships can stop to fill up before leaving on interplanetary missions."

Great, so what do I do?


<sub>...

Sigbro and Richsby joining the regulars, I see.

...

Well, this was pretty at least.</sub>


So. That was a...fun couple hours.

[WillowLuman]

It's avoiding the Mun impact that you'll need to practice in. Generally, unless you want to stay in a body's orbit, you don't want to wait until the encounter itself to adjust your trajectory. Adjust your trajectory in the blue stage, before the encounter itself, to avoid colliding with the body.