Centaur Mass for Jupiter's 4th Lagrange Point

[AllanR]

Hi again

How much mass would a centaur need to have Lagrange points? (is a centaur of this size plausible?)

In the story I'm working on a massive centaur passes near Jupiter's 4th Lagrange point, such that the centaur's Lagrange point and Jupiter's overlap.

Could the centaur come at an angle and velocity, that one could engineer a space station, or one of the Trojans, to be captured by the Centaur? (assume a few years of milli gee acceleration is possible on the object to be captured)

 

[stefan r]

Centaurs orbit the Sun at rate that Jupiter orbits the Sun. An L4 of the Centaur would have to orbit Jupiter at the rate our Centaur orbits Jupiter.

Wikipedia says Lagrange points are only stable if the object ratio is greater than 24.96. A Jupiter mass planet can have a Trojan more massive than Earth.

You might be able to get something like Janus-Epemethius. There is nothing else quite like that but it is stable and worth checking out.

617 Patroklus - Menoelios is interesting enough that NASA is sending LUCY there in 2033. They might be tidally locked (speculation not likely to be caught before 2033) which means we could build a space elevator-bridge connecting them. They are small enough we can bore through the cores. The mass driver rail line can continue in a straight line.

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Could the centaur come at an angle and velocity, that one could engineer a space station, or one of the Trojans, to be captured by the Centaur? (assume a few years of milli gee acceleration is possible on the object to be captured)

Jupiter Trojan orbit to a low Jupiter flyby is very low delta-v. When flying by Jupiter you can use the Oberth effect. The magnitude has a square root which can be heavily leveraged by a space station. For example if your perijove (periapsis) has 50 km/s and you give it a 5 m/s impulse the effect of that impulse is the same as a 500 m/s impulse at apojove.

If you were at the L4 point the station would have effectively circular orbits around Jupiter and the Sun. Almost all Trojans will have elliptical orbits around Jupiter. If you flatten the ellipse the station gets closer to a Jupiter flyby. Once it is flat enough it can flyby the large moons or make a close pass by Jupiter.

 

[AllanR]

Thanks for the reply.
Nice I love hearing about strange objects in our solar system. Both Janus-Epemethiu and Patroklus look fascinating. Will have to include them in a story :)