01:15 <discord-> R​ingo. — How you guys manage to plan a window for the Moon, I can do it, but it's always tough

01:20 <discord-> A​nomaly. — Could you specify your problem more?

01:23 <discord-> R​ingo. — It's tough to launch 3 days before the AN/DN just by eyeballing the trajectory of the Moon

01:23 <discord-> A​nomaly. — You can tell MechJeb to launch into the LAN you want.

01:24 <discord-> R​ingo. — How I do that?

01:24 <discord-> A​nomaly. — Are you familiar with PVG?

01:25 <discord-> R​ingo. — Just for the "basics"

01:25 <discord-> R​ingo. — MechJeb can launch like 3 days before AN/DN so?

01:26 <discord-> R​ingo. — Or whenever

01:28 <discord-> A​nomaly. — You are saying, you want to launch 3 days before the Moon passes the AN/DN?

01:28 <discord-> R​ingo. — Yes

01:28 <discord-> A​nomaly. — MJ can't do that on its own, but that information is provided by Principia.

01:31 <discord-> R​ingo. — How?

01:34 <discord-> A​nomaly. — Principia has an orbital analysis tab, no? You should be able to see the current mean anomaly of the moon, as well as the anomaly of the upcoming node.

01:34 <discord-> A​nomaly. — Dividing 360deg by the difference between the current anomaly and the anomaly of the node, then multiplying by the orbital period will equal the time before the Moon reaches that node.

01:35 <discord-> R​ingo. — Thanks

01:36 <discord-> A​nomaly. — Sorry I got it the wrong way round, it should be dividing the difference by 360deg.

01:37 <discord-> R​ingo. — I'm gonna note that, I'm gonna post in the channel if I have problems with this

01:37 <discord-> R​ingo. — Thanks

02:21 <discord-> s​cimas. — Ehh, as far as I know the orbital analysis only works for vessels, not celestial bodies.

03:33 <discord-> A​nomaly. — I believe you can also hover the mouse over the AN/DN indicator and it will tell you when the body/craft will pass through it.

04:10 <discord-> s​cimas. — True, but that doesn't help if you're looking for a launch window, which is what I believe the original question was. There aren't going to be any AN/DN indicators while you're on the surface.

04:38 <discord-> i​tsRyan. — If you do KoS, I wrote a script that will calculate LAN and launch time for when your launch lattitude's eastern launch plane will intersect the moon's position 3 days into the future. This happens twice every day if you're above the moon's plane. Below the moon's plane, I'd just launch to its plane since that's nearly free. Let me know if you want it.

04:46 <discord-> i​tsRyan. — If you do kOS, I wrote a script that will calculate LAN and launch time for when your launch lattitude's eastern launch plane will intersect the moon's position 3 days into the future. This happens twice every day if you're above the moon's plane. Below the moon's plane, I'd just launch to its plane since that's nearly free. Let me know if you want it. (edited)

04:46 <discord-> l​pg. — I was wondering, besides being written in kOSscript, is there anything inherent to that script that would prevent it from being a standalone tool? (in the style of !calculator and others)

04:46 <discord-> l​pg. — i.e. does it fish data out of the game that a standalone tool wouldn't have access to?

04:48 <discord-> i​tsRyan. — Yeah, it reads the current positions of the moon and launch site, as well as orbital parameters directly. The formulae would work in a spreadsheet if you plugged in the launch position, the current time, and the correct epoch of the moon's orbit start.

04:50 <discord-> i​tsRyan. — (and nobody modifies those parameters later in RSS)

05:05 <discord-> i​tsRyan. — Yeah, it reads the current positions of the moon and launch site, as well as orbital parameters directly. The formulae would work in a spreadsheet if you plugged in the launch position, the current time, and the correct moon position and Earth rotation angle at the epoch start. (edited)

09:18 <discord-> e​gg. — > nobody modifies those parameters later in RSS

09:18 <discord-> e​gg. — but Principia does, that is its main point

10:39 <discord-> G​erman Mew. — Is/will photon stab be added to principia. I would love to stab my deep space probes that way ( less rcs use )

10:51 <discord-> R​ingo. — @itsRyan I don't have kOS, but maybe I can try, I've heard about this mod

12:14 <discord-> R​ingo. — How I can see the current anomaly and the anomaly of the node in the Tracking Station?

12:17 <discord-> R​ingo. — Or just have the Orbit analysis of the Moon in the Tracking Station?

12:17 <discord-> R​ingo. — Or just see the Orbit analysis of the Moon in the Tracking Station? (edited)

13:22 <discord-> R​ingo. — 🤔

13:25 <discord-> S​tonesmile. — If i recall correctly, the orbit analyzer hasn't been implemented for bodies yet, so a bit tricky to get them from principia, but the values given by for example MJ might be good enough

13:25 <discord-> R​ingo. — Which values from MJ?

13:26 <discord-> R​ingo. — From the "Rendezvous Planner"?

13:26 <discord-> S​tonesmile. — You can create custom windows, where you might find these values under Target

13:28 <discord-> R​ingo. — So the values are correct with MJ?

13:30 <discord-> S​tonesmile. — Not sure, but they should be decent enough

13:41 <discord-> R​ingo. — "N/A" 🤷‍♂️

13:41 <discord-> R​ingo. — https://cdn.discordapp.com/attachments/480397772248580098/738028457690398790/unknown.png

13:43 <discord-> R​ingo. — The time to DN or AN stays to 14min56

13:43 <discord-> R​ingo. — https://cdn.discordapp.com/attachments/480397772248580098/738028826411401296/unknown.png

13:43 <discord-> R​ingo. — Even if I speed up the time

13:47 <discord-> R​ingo. — I guess it goes to #mechjeb-pvg

14:08 <discord-> R​ingo. — I don't find values related to the target, or they're wrong :/

14:11 <discord-> G​erman Mew. — > I don't find values related to the target, or they're wrong :/

14:11 <discord-> G​erman Mew. — @Ringo start when relativ inclination is pretty low. That’s the best way if u don’t want to start from kurou/ use the kos Skript from itsryan ( could be wrong just my experience)

14:12 <discord-> R​ingo. — Where I can fin the kOS script?

14:12 <discord-> R​ingo. — From Itsryan

14:14 <discord-> G​erman Mew. — https://github.com/ryanc55/KOS-Scripts/blob/master/moonlaunchwindow.ks

14:14 <discord-> R​ingo. — Thank you

14:14 <discord-> R​ingo. — So in your experience, it was sometimes wrong?

14:16 <discord-> G​erman Mew. — Doing it with relativ inclination u can get 5-27 degree margins. 5 degree aren’t that bad tbh

14:55 <discord-> S​tonesmile. — Trying to create an exterior ballistic capture to the moon, like GRAIL. What is the minimum dV requred to capture into a semi-circular orbit once at the moon?

14:57 <discord-> S​tonesmile. — GRAIL had about 1k dv per orbiter, but i assume some/most of that was for orbit maintenance

16:08 <discord-> Z​eusbeer. — Like 30dv to capture, its a joke if you do it right

16:08 <discord-> Z​eusbeer. — M/s,

16:08 <discord-> Z​eusbeer. — M/s* (edited)

16:11 <discord-> Z​eusbeer. — basically, the idea with a ballistic capture, is that it almost captures itself. the hardest part about it is getting the perfect angle, but it's possible

16:11 <discord-> Z​eusbeer. — basically, the idea with a ballistic capture, is that it almost captures itself. The hardest part about it is getting the perfect angle, but it's possible (edited)

16:20 <discord-> S​tonesmile. — @Zeusbeer you did one in stock right? I think the hardest part for me is to launch into the correct plane in RSS

16:21 <discord-> Z​eusbeer. — actually, yesterday, I did one in RSS

16:21 <discord-> Z​eusbeer. — what you have to do, is pull the prograde so high that's it's barely not an escape trajectory

16:22 <discord-> Z​eusbeer. — and then move the time slider around till your periapsis gets close to the moons orbit

16:22 <discord-> Z​eusbeer. — and then fine tune with some correction burns later in the plan

16:22 <discord-> Z​eusbeer. — it could take up to +- 90 days

16:23 <discord-> Z​eusbeer. — also, if your out of plane, you can burn prograde till your periapsis is as high as it's gonna get

16:23 <discord-> Z​eusbeer. — and then do a binormal correction at a cheap point, which should help it out

16:23 <discord-> Z​eusbeer. — also, if your out of plane, you can burn prograde till your periapsis is as high as it's gonna get, while your apoapsis still not on escape (edited)

16:25 <discord-> S​tonesmile. — Yeah, I know that I have to launch to Earth-Sun L1, but the best capture i have managed is still ~300 m/s

16:25 <discord-> Z​eusbeer. — corrections take a lot of deltaV

16:26 <discord-> Z​eusbeer. — you have to correct till your spacecraft makes a few loops around the moon

16:26 <discord-> Z​eusbeer. — for the cheapest capture

16:26 <discord-> S​tonesmile. — The binormal correction was only about 50 dV

16:26 <discord-> Z​eusbeer. — how many loops would your spacecraft have made if you didn't capture?

16:27 <discord-> S​tonesmile. — about 5, it might be that I targeted a too circular orbit

16:27 <discord-> S​tonesmile. — it's still 300 m/s down from 900 m/s

16:27 <discord-> Z​eusbeer. — hmm

16:27 <discord-> Z​eusbeer. — is that with complete circularization?

16:28 <discord-> Z​eusbeer. — or just capture

16:28 <discord-> S​tonesmile. — yeah, quite circular

16:28 <discord-> Z​eusbeer. — yeah the extra circularization burn takes up a lot of deltaV, but capturing for a quite stable elliptical orbit should be quite cheap

16:29 <discord-> S​tonesmile. — Yeah, so I managed a good capture then, good to know

16:29 <discord-> Z​eusbeer. — actually really good, 5 loops is quite well done

16:35 <discord-> Z​eusbeer. — also, 49m/s binormal? teach me 🙂

16:37 <discord-> S​tonesmile. — I launched at morning/evening to get my AN/DN close to the burn to E-S L1, I *think* that minimizes the plane correction at AP

16:41 <discord-> S​tonesmile. — Reasoning being that the velocity at L1 is minimized (?)

17:27 <discord-> s​cimas. — @egg Something is broken with the flight plan rendering in the target LVLH frame. I can't get it to render the trajectory beyond ~ 3h 20 min from "now." Now = current time, not the flight plan base time. All other frame trajectories render just fine, with or without a target selected.

17:29 <discord-> l​pg. — target frame flight plans are also limited by the prediction duration (purple line)

17:29 <discord-> s​cimas. — Oh, huh, yeah, just figured that out. Wasn't expecting that.

17:30 <discord-> l​pg. — gotta know where the target will be in order to show where you'll be relative to it

17:30 <discord-> s​cimas. — Was it always like this, I don't seem to remember it working like that.

17:53 <discord-> e​gg. — yes, for the reasons outlined by @lpg, though the details of the interaction may have changed in Fano with asynchronous prediction computation

19:15 <discord-> R​ingo. — First time that I use the kOS script from @itsRyan for Moon launch window , very useful ,thanks a lot

19:15 <discord-> R​ingo. — https://cdn.discordapp.com/attachments/480397772248580098/738112473248301136/unknown.png