Eccentricity is a way of characterizing the curve the object makes around the sun. <1 is an ellipse, and so the object would be in orbit around the sun, and hence probably not interstellar. >1 is hyperbolic, and thus not gravitationally bound to the sun, and so probably interstellar.
The closer the eccentricity is to 1 without being equal or less, the more "curved" the trajectory is and the nearer its closes approach to the sun will be.
> The closer the eccentricity is to 1 without being equal or less, the more "curved" the trajectory is and the nearer its closes approach to the sun will be.
Is this true? I thought it depends on the object’s speed. You can have an object with e=3 have a closer approach to the sun than an object with e=2 if the first object is traveling sufficiently faster.
In other words, at a given perihelion, you can change an object’s e by accelerating or decelerating. Not a orbital mechanics major, just played too much KSP.
The closer the eccentricity is to 1 without being equal or less, the more "curved" the trajectory is and the nearer its closes approach to the sun will be.