How to Use a Planisphere
- 1). Prepare the planisphere for viewing. Position the planisphere with the star listings and constellations in front of you.
- 2). Set the planisphere time settings. Rotate the circular window to observe the current time and date. The days and months are marked on the edge representing the sky; the times are marked on the inner edge. For example, if you are in New York on March 10th observing the sky at 6 PM, then you will rotate the window to align 6 PM with March 10th.
- 3). Examine the stars through the viewfinder. Look through the hole in the planisphere to view the stars. The view that is visible represents the star locations at the date and time that has been selected.
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