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As an example, look at Earth's only confirmed Trojan By Phoenix7777 - Own work Data source: HORIZONS System, JPL, NASA, CC BY-SA 4.0, source Now, to understand what is happening here. The yellow dot is the sun. The blue dot is the Earth. Although the Earth is orbiting the sun, the "camera" is turning so that it appears that the Earth is roughly ...


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The mass of the Trojans (both camps as far as I know) is estimated at around 0.0001 Earth masses (reference) (Note that this number is debated). The density of them vary but the highest found is around 2.5 g/cm^3 (reference) Assuming that the composition is mainly rocky/icy with very little gas, the act of combining all of them should make a rocky/icy object ...


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The Jupiter Trojans are not at the Sun-Jupiter L4 and L5 Lagrange points. They are instead in pseudo orbits about those points. These pseudo orbits appear from the perspective of a frame of reference that rotates at Jupiter's orbital rate (i.e., a frame in which the Sun and Jupiter are more or less fixed). Unlike central body motion, which results in planar ...


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Trojan asteroids are in roughly circular orbits around the Sun at roughly the same distance as Jupiter, that are in 1:1 resonance with Jupiter and stay very roughly 60 degrees away from it. Scott Manley's video below shows two classes of asteroids in resonance with Jupiter. The first one shown is confusing because it is in a 3:2 resonance and in the rotating ...


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There is a symmetry in the rotating gravitational field, which means that capture of an asteroid to the L4 is just as likely as to the L5 Lagrange point. In the case of Mars the split is 1:6, and a simple binomial model suggests a probability of 0.0625 (the probability of a 1:6 or 0:7 split given the hypothesis that they are distributed randomly is 0.0625) ...


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In short, most of the trojans stay orbiting arround L4 or L5. These can be called tad-pole orbit asteroids. There are some trojan asteroids, however, that their orbit never get's too close to L4 nor L5 to get trapped and have a tad-pole orbit, or they do but they have too much energy to get trapped. These trojan asteroids have larger orbits, following a ...


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They are pulled out of stable orbits by Jupiter. The details are in https://ui.adsabs.harvard.edu/abs/2012jsrs.conf..225B/abstract Full text https://syrte.obspm.fr/jsr/journees2011/pdf/baudisch.pdf The planet Jupiter is solely responsible for the hole of instability for short time integrations ($T < 10^{7}$) compared to the age of the planetary system. ...


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There is essentially no room in our habitable zone for another Earth-sized planet. The exact timescale for instability would depend on the details of where you put it, but the system couldn't survive long term. Most investigations of the long-standing question of solar system stability (without any additional planets) find that the system is stable in the ...


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The least stable orbits are likely the temporarily captured orbiters of Earth and other planets. These are bodies that have been captured by the Earth/Moon gravity well and move from solar orbits to terrestrial orbits. They normally have complex orbits that take them well beyond the orbit of the Moon and most don't last long. Most such objects are small, ...


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Answer posted under the wire during closure. Others may be able to write an additional and/or different answer as soon as two more reopen votes are cast. Would it have been possible to send a radio signal towards ʻOumuamua? Yes. It is certainly true that at any time, a large radio telescope or even a small transmitter can always sent a signal toward ...


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I post an answer from the comment. Trojan satellites or trojan moon are natural satellites that are in the lagrangian point (L4 and L5) of another bigger (more massive) moon. All the known examples are Saturn's moon. In particular Tethys and Dione have other moon in their lagrangian point L4 and L5


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Are their orbits circular as Neptune's (in this case) or highly eccentrical? L4 and L5 stability is rather narrow Source: http://ccar.colorado.edu/asen5050/projects/projects_2010/singh/ A more elliptical or eccentric orbit in resonance with a planet with a circular orbit would reach well outside of L4 and L5 and wouldn't be an L4 or L5 object. (though ...


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There is one known earth Trojan - http://en.wikipedia.org/wiki/Earth_trojan The reason L1, L2 and L3 aren't stable is covered here: https://physics.stackexchange.com/questions/36092/why-are-l4-and-l5-lagrangian-points-stable The reason the earth has so few L4 and L5 asteroids is cause other planets like Jupiter and Venus tend to destabilize the orbits - ...


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