Hunt for trojans

This is really great - also know what you mean by algorithm, i forgot about EDSM database dumps silly me given iv used them to do HR diagrams haha

I did actually locate what looked like a Trojan Moon, though its likely just a coorbiting moon more than a true orbit at a Lagrange point. I have to locate my exploration note pad (moved houses, its in a box somewhere still) These objects have always been interesting to me, and while my alt is out in the middle of nowhere, ill keep an eye out for them
 
My submission. Blua Byoe IZ-D b14-0.
Found these last night. Unfortunately I forgot to take another measurement from the other moon but since they share the same orbital plane and orbital period I don't think it's an issue.
Weird, EDSM doesn't have the celestial bodies of the system yet.
Blua Byoe IZ-D b14-0(Blua Byoe IZ-D b14-0 4 a)_00004.pngBlua Byoe IZ-D b14-0(Blua Byoe IZ-D b14-0 4 a)_00003.png
They're really close to the rings too.
View from A
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View from B, they're pretty much identical, they both have the same composition.
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Unfortunately I forgot to take another measurement from the other moon but since they share the same orbital plane and orbital period I don't think it's an issue.
The primary qualification for Trojanity is that the smaller planet/moon is sitting in the L4 or L5 point of the larger, such that they share the same orbit but are separated by 60 degrees. So I don't think those moons 4a and 4b are actually Trojans - they're not separated by 60 degrees; it looks more like 110 degrees. and the slightly thicker grey orbital line they are sitting on makes me think that they almost, but not quite, have the same orbital period ("0.8 days" is likely to be rounded considerably; one might be 0.788, the other 0.789, for example). So, certainly interesting, but alas, not a Trojan.

Weird, EDSM doesn't have the celestial bodies of the system yet.
I assume you are actually running EDD or some other third-party programme that sends data to EDSM? EDSM does not connect directly to the game, it depends on people submitting data to it. If you're running EDD, the celstial body info should transfer across immediately, but there may have been a connection glitch with EDSM at the time you visited the system; try clicking on the "send unsynced logs to EDSM" button.
 
and the slightly thicker grey orbital line they are sitting on makes me think that they almost, but not quite, have the same orbital period
That's the way Elite plots these lines. It's a bit faulty and depends on the zoom level.
First there is one thick line, then there are two lines and finally it's just one line.
Screenshot_0197.jpgScreenshot_0198.jpgScreenshot_0199.jpg
 
Sorry to bump but I got pointed out to this thread again.
We know there are trojan moons and planets, but what about Gas Giants?
Found two GGs with ammonia based life with the same orbital period, eccentricity and inclination.
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Distances are the same from both one body to the other and the star.
 
Yep, that be a Trojan, then. Even though this system "fails" the mass ratio test (the mass ratio here is 69.16 : 5.15, or 13.4 : 1 - well below the 100:1 needed for a truly long-term-stable Trojan pairing. Still, the Stellar Forge created it, so it counts.

Giant-Giant pairings are reasonably common (for Trojans, that is), though specific pairings might be scarce. For example, by my count, Orvidius' list currently has 5414 Trojan pairs. Out of those, just four of them (Blua Blou QU-D d13-40 8/9, Drojaea UY-R d4-3 4/5, Phroea Eaec ZG-E b2-0 1/2 and Praea Euq HN-X c16-1 3/4) are GGABL-GGABL pairs.
 
Yep, that be a Trojan, then. Even though this system "fails" the mass ratio test (the mass ratio here is 69.16 : 5.15, or 13.4 : 1 - well below the 100:1 needed for a truly long-term-stable Trojan pairing. Still, the Stellar Forge created it, so it counts.
The mass ratio required for stable orbits at L4/L5 points is actually 24.96:1, not 100:1 - and that's actually between the central body of the system (the star) and the more massive planet. I'm not sure if anyone's actually run the numbers on whether there's an upper limiit of mass for the trojan objects themselves compared to the main planet in their orbit that they're 60° ahead/behind of.
 
The mass ratio required for stable orbits at L4/L5 points is actually 24.96:1, not 100:1 - and that's actually between the central body of the system (the star) and the more massive planet. I'm not sure if anyone's actually run the numbers on whether there's an upper limiit of mass for the trojan objects themselves compared to the main planet in their orbit that they're 60° ahead/behind of.
Based on what I've read, that's the lower limit for being minimally stable. That is, anything below that will not be stable. However, if you want it to be reliably stable for millions or billions of years, it needs to be higher, and the rule of thumb seems to be about 100:1. As far as I know this gets applied to both the ratio between the two planetary bodies, and the larger body and its parent.

I'm totally not an expert, just reporting what I've read in various articles and on wikipedia. :)
 
There's a really good article on it here: http://spaceengine.org/articles/lagrange-points-and-trojan-orbits/
See also this post for an examination of how the mass ratio affects orbits at L4/L5: http://forum.spaceengine.org/viewtopic.php?t=446&start=75#p31064 - increasing the mass ratio only really seems to tighten the object's orbit around the L point, I think it's still stable no matter what though above 25:1. (though gravitational interaction from other bodies in the system would probably affect the stability too)
 
Interesting, so as long as the ratio 1:~25 (or better) is maintained between the total mass of the two bodies to the parent (star), then it can be stable -- As a rule of thumb. That clarifies a lot. I appreciate the level of detail that they go into with it. Sometimes the simple rule needs a lot of explanation to understand why.
 
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