Sky & Telescope's Triton Tracker
Neptune, at magnitude 8, is the beyond the reach of the naked eye and even some binoculars. Locating the most distant planet can be a bit daunting on its own. But if you are up for a serious challenge, you can go further and try spotting its largest moon, Triton.
Next comes the date and time; when the routine opens, it is initialized to the present (as determined from your computer's clock). Change the date and time by entering new values in the corresponding boxes and clicking the dark gray Recalculate button on the next row. Or click on the adjacent buttons to step backward or forward in increments of 1 day or 1 hour.
Our Triton Tracker uses Universal Time (UT, the same as Greenwich Mean Time), and underneath the day- and hour-increment buttons it shows what we think is the offset between UT and your local time, based on your computer's current settings. When changing the time manually using the Time input box, enter the Universal Time that corresponds to the local time when you will be observing.