Is There an Orbital Mechanic in the House?

[Grav_Moped]

I'm working on Boughene (a non-standard one -- it's the TravellerWorlds version you get from TravellerMap if you force placement of the mainworld as a satellite*, that is, Boughene orbits the gas giant Komesh along with 4 other moons).

Here's how you make it (basically, come in to TravWorlds via TravMap, set "place main world as satellite", save the preference, back out and come back in again)

Here's the problem (basically, that a "Boughene Month" -- one orbit around Komesh -- is very close to a "Komesh Year" -- one of its orbits around the un-named star).

Here are my questions:
1. Is this stable?
2. Would it be more stable if Boughene was at the L4 or L5 Lagrange point of the star-Komesh system?

What are the odds this could happen naturally? Is this whole dang star system an Ancients Artifact?

-------------------------
*Oops. My bad: locked a preference setting in without noticing. But I spent months running a PbP scenario that assumed it was correct, so continuity and all that...

 

[Grav_Moped]

Well, no.

Boughene would have to be orbiting Komesh at the same distance as Komesh orbits Unnamed Star (0.26AU), as the L4/L5 (Trojan) points are in the orbit of the planet and equidistant from the star and planet. Boughene orbits Komesh at 0.09AU, which isn't even in the ballpark.

Nice theory while it lasted, anyhow. I'm still not sure where my math error is (or if there actually isn't one and I just am just reading all of this wrong somehow).

 

[Spinward Flow]

You're just running into the same problem that I did with the TravellerWorld randomization settings producing something that is "rules legal" but still "reality deficient" when looked at objectively.

Komesh orbits the M1V primary star at 0.26AU.
Boughene (the moon) orbits Komesh as 0.09AU.

This means that Boughene's orbit moves it from 0.17-0.35AU distant from the star as it orbits around Komesh ... which is extremely unlikely to be a long term stable orbital distance.

A closer orbit to Komesh would be perfectly fine, but a moon orbiting that far away from a planet that close to a primary star makes little sense to anyone who knows anything about orbital mechanics (let alone stable ones).

 

[Grav_Moped]

A closer orbit to Komesh would be perfectly fine, but a moon orbiting that far away from a planet that close to a primary star makes little sense to anyone who knows anything about orbital mechanics (let alone stable ones).

Which suggests that it might have drifted into the L5 (trailing Trojan) point by chance (or just time and gravity)... LOL. Or, maybe it was put there a few hundred thousand years ago by the folks who could move planets around in that era. That'd be a useful post hoc justification for the Scout Base (not that anyone's actually found anything, but it wasn't for lack of trying -- it's fair to posit that they've long since given up by now).

Alternately, it could be in a (even more unlikely) precessing polar orbit.

 

[Spinward Flow]

Or Boughene (the moon) could be a capture that is in an orbit of temporary stability (for a few thousand years?) before it gets stripped from Komesh by gravitational forces and slung off in who knows what direction.

In fact, I would go so far as to say that having Boughene (the moon) be a "captured transient" would possibly make for the most interesting possibility, especially given the size of Boughene (the moon) with a Diameter: 8 (Terra-sized!).

Could even be a case of Boughene originally having been an interstellar "rogue planet" that entered the Boughene system but wound up getting captured by Komesh, in which case Boughene (the moon) and Boughene Station are rather unlikely to be orbiting Komesh in the equatorial plane.

Heck, Boughene (the moon) could even be in a highly inclined retrograde orbit around Komesh!
Now wouldn't THAT be interesting!

 

[Grav_Moped]

Oh, that's nice.

I see how the system-gen made it happen.
1. force mainworld as satellite.
2. mainworld has to be in hab zone.
3. place gas giant in hab zone (not usually a problem, but Unnamed Star is small and dim so ya gotta be right next to it...)
4. build moon system of gas giant (not usually a problem)
5. plug mainworld into moon system randomly (though probably bias it outward so tidal forces don't turn it into a tectonic nightmare).
6. resulting orbit is so far out as to render it unstable. Oops.

 

[BackworldTraveller]

The "Capture" idea works well with the "B" atmosphere. To have got where it is it would almost certainly have had to hit something relatively large to slow enough to not just leave on hyperbolic orbit. The "B" could be the result of that. Now where are all the other bits from that crash?

 

[Spinward Flow]

Now where are all the other bits from that crash?

Moons 2, 3 and 5 of Komesh ALL have Atmosphere: B ... and they're all Diameter: 8-9.

Where did the other bits from that crash go?
Easy answer ... INTO THE OTHER MOONS of Komesh!