The rocket equation,the difference between momentum change (linear) and energy (quadratic) in Vexhaust of rockets, and the laws of thermodynamics constrain us t

The rocket equation,the difference between momentum change (linear) and energy (quadratic) in Vexhaust of rockets, and the laws of thermodynamics constrain us to low speeds if we actually want to stop anywhere rather than sail by in a few seconds, which doesn't get you much more than good telescopes do, if anything. Slow travel is also a lot safer because of kinetic energy being quadratic in v. If a vessel can be made that survives travel durations of thousands of years, and the passengers likewise, then they're adapted for life in interstellar space, and won't see much point in expending a lot of energy to go far down a gravity well to a hostile environment. Telescopes are fine for observation. There's plenty of stuff in Kuiper belts. The locals won't be interesting until they get out to their own Kuiper belt anyway.