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It does. If you turn on the solar pressure radiation you need to set the mass of spacecraft, SRP area and coefficient of reflectivity. And it really makes a difference. I tried to integrate in GMAT trajectories of real spacecrafts and without including the solar pressure into calculation I had...

Honestly, I don't think all this spaceship details are relevant in our case because anyway we get the significant mismatch between the Orbiter and GMAT integrations from using VSOP87 in Orbiter. My usual approach is to use simplified models without the solar pressure radiation, the...

Yes, it might be more convenient than to do it manually. Just one remark. It's better to use TDBModJulian instead of UTCModJulian for the maximum precision.

Yes, Orbiter uses the ecliptic coordinate system and VSOP87 uses the J2000 epoch.

For coordinates : just divide/multiply by 1000 and swap Y and Z For time epoch: TDBModJulian+29999.5= Orbiter MJD

I think, any program that looks like this can do it ;)

BTW, it's very easy to create illustrations for those hyperbolas with GMAT: Create Spacecraft DefaultSC; GMAT DefaultSC.DateFormat = TAIModJulian; GMAT DefaultSC.Epoch = '21545'; GMAT DefaultSC.CoordinateSystem = EarthMJ2000Ec; GMAT DefaultSC.DisplayStateType = OutgoingAsymptote; GMAT...

It's good. I wish I had such explanation when I tried to use TransX first time ;) They call it "outgoing asymptote direction" in NASA ;) I think, there are two hyperbolic orbit passing over the launch site, but taking into account the planet rotation one is always more preferable than other.

I've checked it in Orbiler, and it works. There is a "lodestar" (for the green trajectory) that can be used to target LOP-G from Brighton-Beach: GL-03:DeltaGlider STATUS Orbiting Moon RPOS -3111927.892 -26616079.085 -14832641.036 RVEL 8.0341 435.9435 99.7092

GMAT gives an interesting solution: The green line is the trajectory to the LOP-G from a low circular orbit above Brighton-Beach and the yellow is the return trajectory. The most interesting fact is that we need less than 200 m/s at the apoapsis to align speed with LOP-G, dock, and then to...

You are right, Moon turns with NRHO plane , my mistake.

Thanks again. To watch graphs and videos it's very different from "to touch" those orbits in Orbiter or GMAT. And without your scenario I wouldn't know where to start from and what an initial guess to choose searching for NRHO-like orbits. Currently for this scenario I see two opposing...

Yes, with your periapsis it is less stable, but still, it should be possible to do more than 2-3 revolutions: RPOS -15969338.210 -3884420.146 -5698604.470 RVEL 368.6800 556.7144 165.8636

Yes, the periapsis was redused by GMAT. BTW, they want to use a low perilune for LOP-G too: https://en.wikipedia.org/wiki/Lunar_Orbital_Platform-Gateway The LOP-G would be placed in a highly elliptical near-rectilinear halo orbit (NRHO) around the Moon which will bring the station within 1,500...

It has to be more than 2-3 revolutions. For example try this values (for the same Date MJD 52013.754909351): RPOS -12142686.086 -14397704.633 -5091606.013 RVEL 176.6108 590.1609 100.3061 I'm not sure if it is exactly a NRHO, I didn't do the math, just did a simple "brute-force" optimization...

Something odd. GL-02 escapes Moon after two revolutions. Is this really NRHO? Can you recheck, please?

Where is "Date MJD" ?

I've rewritten the code of this amazing Keithth G's tool for new Pykep/Pygmo v 2.x and Python v3.6 with some improvements such as multi-revolution solutions, checking of altitude, SPICE and GMAT suppport, trajectory plot, sequenced input. It's based on the Keithth G's code (from...

I have a suspicion that the most efficient L1->L2 transfer trajectory between symmetric planar Lyapunov orbits should look like this.

Thanks! A very interesting topic. I'm trying now to get deeper into the subject too. There is a transfer from a planar Lyapunov orbit L1 to L2, e.g. :)