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A comment on Another Interstellar Object Detected in the Solar System. Parent comment

Re:Another Interstellar Object Detected in the Solar System by _kst_ on Thursday September 12, 2019 @01:08AM (#20948194)
An interstellar object cannot be captured into a stable orbit unless some other force (such as Jupiter's gravity) acts on it.

Orbits are time-symmetric, so an interstellar object being captured into a stable elliptical orbit would be equivalent to an object in a stable elliptical orbit escaping the Solar System (again, ignoring other influences).

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Re:Another Interstellar Object Detected in the Solar System by tempestn on Thursday September 12, 2019 @02:41AM (#20948666)
Is that true of comets as well? It seems conceivable to me that the sun could spin it around such that the comet's off-gassing could reduce its speed and allow it to be captured. Obviously unlikely, and highly dependent on conditions (in particular incoming velocity) but possible.
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Re:Another Interstellar Object Detected in the Solar System by lojack on Thursday September 12, 2019 @09:52AM (#20951431)
If you're ignoring all other influences then there is no such thing as interstellar objects. By definition, every object in a two body system are gravationally bound to each other.
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Re:Another Interstellar Object Detected in the Solar System by ravar on Thursday September 12, 2019 @12:57PM (#20953707)
This is so wrong. Objects can have enough energy that will become arbitrary far apart as time passes. In no sense are the objects bound together in that case.
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