As a graduate student at UT, I made several visits to McDonald Observatory. One night in particular stands out in my mind. In the early morning hours Comet Hale-Bopp was hanging above the horizon, looking absolutely spectacular in the observatory's dark skies.
During the overnight hours, any calls to the observatory were routed to the 107-inch control room, where I was running the telescope. The phone rang and the caller asked, "What is that thing in the sky that looks like a comet?" I replied, "You're exactly right — it's a comet!"