Visually Tracking Starships

I think I know the scientific answer to this but want to explore the subject with everyone.   I'm thinking of an amateur astronomer watching starships thrusting out of a system or breaking on the way into a system.  Would the exhaust of the engines be visible to the astronomer with some nice telescopes?<div><br /></div><div> I'm thinking the guy knows when in the year the common trajectories of ships along the jump routes are within observational range of him for the planet or moon he is on as the ships go to and from the major planet in the system.  He is not on the major planet. </div>