Completing the "Explore The Mun" contract

[S.Bartfast]

I'm slowly working my way through this game and after completing my first successful fly by of the Mun I picked up a contract called "Explore The Mun." and was expecting to more or less repeat the same expedition and collect the contract but upon my eventual return all three requirements are listed as being "Incomplete":

 

I definitely flew very close to the Mun on my flight (PE 6,000m) and did several experiments with my thermometer, barometer, mystery goo as well as the "Science Jr". I also did several EVAs to collect the data and made a successful return (and was awarded several hundred science points for my efforts) however all three stages of this contract remain "Incomplete".

How do I actually complete this contract?

[peteletroll]

Did you orbit the Mun, or did you just fly by? Looks like the contract requires an orbit.

[S.Bartfast]

Just now, peteletroll said:

Did you orbit the Mun, or did you just fly by? Looks like the contract requires an orbit.

It was just a "fly by".

I wasn't sure exactly what constituted an orbit but seem to read that simply entering the Mun's SOI should be enough.

As it was I was trying to repeat the expedition before upgrading my launchpad and with being limited to only 18t I simply couldn't get enough fuel up there to achieve a stable lunar orbit. Do I actually need to conduct a full 360° orbit while in the Mun's SOI for it to be counted as "an orbit" do I?

Guess an upgrade or two will be in order then.

[peteletroll]

You don't have to make a full orbit, but you have to be in orbit with your craft when you EVA.

[Streetwind]

...In other words, you need an apoapsis inside the Mun's sphere of influence, and a periapsis above its surface.

Mind you, it doesn't have to be a low or circular orbit. It can be as eccentric as you like. The apoapsis can be just a few kilometers short of escaping. And my gut feeling says it ought to be possible within an 18-ton, 30-part limit, if built well.

...Okay, I did the math, try the following: parachute, pod, decoupler, 3x FL-T200, terrier, decoupler, 2x FL-T800 (or equivalent smaller tanks), reliant. Remove the monopropellant from the pod. Now you should have a liftoff TWR of 1.39 and close to 5600 m/s vacuum dV. Your mission should take roughly 3500 + 850 + 300 + 300 = 4950, let's round to 5000 m/s. That's with braking into an unnecessarily low and circular 10x10 km munar orbit, and returning back to Kerbin from the same. And there's already a small bit of margin in those numbers to begin with, nevermind the 600 m/s additional dV the rocket will have. All within 11 to 17 parts, and just over 15 tons.

Edited July 8, 2020 by Streetwind

[S.Bartfast]

1 hour ago, Streetwind said:

...In other words, you need an apoapsis inside the Mun's sphere of influence, and a periapsis above its surface.

Mind you, it doesn't have to be a low or circular orbit. It can be as eccentric as you like. The apoapsis can be just a few kilometers short of escaping. And my gut feeling says it ought to be possible within an 18-ton, 30-part limit, if built well.

In fact, try the following: parachute, pod, decoupler, 3x FL-T200, terrier, decoupler, 2x FL-T800 (or equivalent smaller tanks), reliant. Remove the monopropellant from the pod. Now you should have a liftoff TWR of 1.39 and close to 5600 m/s vacuum dV. Your mission should take roughly 3500 + 850 + 300 + 300 = 4950, let's round to 5000 m/s. That's with braking into an unnecessarily low and circular 10x10 km munar orbit, and returning back to Kerbin from the same. And there's already a small bit of margin in those numbers to begin with, nevermind the 600 m/s additional dV the rocket will have. All within 11 to 17 parts, and just over 15 tons.

Oow, that sounds like fun.

However I did just upgrade my launch pad and simply strapped two "Thumpers" to the same craft I used last time and made a nice circular ~7.5km orbit of the Mun, collecting an EVA Report over every section of terrain I covered and still made it home with fuel to spare.

While I don't doubt your numbers there @Streetwind I do very much doubt my ability to pull it off. To be honest I was flat out just managing a simple "fly-by" and making it back myself. As it was, I would have left many a Kerbonaut floating about out there if it weren't for the good old "Revert to launch" option and God only knows how many I'd leave floating if I were to attempt a proper orbit of the Mun as well:

Edit: Oh, and yes. When I returned to Kerbin after orbiting the Mun properly the mission was indeed counted as a success. Thank you: 

Edited July 8, 2020 by S.Bartfast

[bewing]

As far as managing the contract itself goes, there are two ways of viewing a contract. Your image seems to show the contract from inside Mission Control. If you think about if for a really long time, Mission Control does not know which craft you were using to try to complete the mission. Some craft may have flown by the mun. Some kerbals from different craft may have gone EVA. Some other missions may have landed back at Kerbin. So which of those various missions and craft should Mission Control be using to try to figure out partial credit? It can't.

If, instead, you look at the contract using your "Messaging App" when you are in flight mode, it knows that you mean "assuming the currently selected craft", and it will show partial credit.

As the others said, the contract requires that you make a burn in the Mun's SOI to close your Munar orbit. You can leave again immediately, but you need to do that burn -- a flyby does not count.

 

[king of nowhere]

by the way, since you were at risk of not having enough fuel to return, i think you may find useful a deltaV map: it allows you to calculate how much fuel you'll need for any mission.

here is the deltaV map

and here are instructions to read it, if it laves you baffled

with the map you can readily calculate that once you are in kerbin orbit, you need 860 m/s to get on a mun intercept, 280 m/s to enter a circular low orbit around mun, another 280 m/s to get back to kerbin intercept. you'd need additional 860+3400 m/s to land, but you lose those by aerobraking. so, once you got into a mun intercept, you only needed an extra 500 m/s to also get orbit.

those values assume optimized trajectories