Interstellar Approach — Art of War in Approaching a Solar System

On earth a ballistic projectile follows a parabole, but how would you go ballistically in a solar system?
So that approached planet doesn’t suspect agency in your trajectory.

If such a concern was valid in approach, it would also mean you can’t change direction once you hit the gas from unobservable distance.

Unobservable distance would be variant on a spectrum range. Based on your optimism how early/late in technology your approached galaxy is.

Such a concern would also mean, multiple ballistic passby for intelligence collection would be better form of attack.

First a probe, then a secondary probe for specific planet identified as point of interest.

And finally the landing collossus, to take on the planet without giving them a headsup of the incoming interstellar attack.

Inspiration : Oumuamua, and yet another upcoming asteroid is soon to passby our solar system in few years. Except this one is bigger. It is going to pass by Mars, which might have been the suspect planet for the “interstellars”.