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Using Phillip's Planisphere (question)

Started by George Victor, 02/24/2003 03:53PM
Posted 02/24/2003 03:53PM Opening Post
I hope this is the right section of the forum to post this. I guess the Star Wheel is "Equipment".
I just received a Phillip's Planisphere and have a question on its use for sunrise and sunset. I have read the directions on the back several times and just don't get it.
Thanks in advance.
George
Posted 02/24/2003 06:35PM #1
George,
The easiest way to get your bearings with a Planisphere is this. Set the clock dial to the day/ month dial for the time/day/month you want to observe. Now hold the planisphere up in front of you while facing south. The time/day month setting will show you exactly whaty the sky looks like at that time. If you want to see what the sky would look like at sunrise or sunset, set that time of day to the appropriate day/month and it will show what the sky looks like at that hour.

The bottom of the planisphere window represents south. The rivet hole represents the north star, Polaris. the line up thru the center of the planisphere should show you the stars right up thru the meridian in the sky. When facing south with the planisphere in hand, left is east in the sky and on the planisphere.

Its a bit more difficult using the planishere to find things in the north circumpolar area.

Remember this. the planisphere is trying to place a map of a half circle section of the sky on a flat surface. If you could bend the planisphere into the shape of a bowl, it would take on the shape of the sky overhead.

hope this helps, edz.