How to Use a Planisphere
A planisphere is a rotating star chart that allows you to dial in the entire visible sky for any day and time of the year and with great precision.
What we want to share with you here is how to use any planisphere you might purchase or make yourself that is set up for the Northern Hemisphere.
Step 1: Notice that the planisphere has every day of the year marked on the inside wheel, as seen below:
Step 2: Notice that the rotating outer wheel has the hours of the day and night, as seen below:
Step 3: To see what your sky is like tonight, slide the the rotating outer wheel to match the date to the time of night.
Step 4: If you are on Daylight Savings Time, remember to subtract an hour.
Step 5: Hold the planisphere over your head and point the corner of the planisphere marked "North" to the northern sky. What you see on the planisphere as you gaze upward will match what your are seeing in the sky.
That is basically it. There are more complicated and interesting things you can do depending on the planisphere you make or purchase, but all properly made rotating star charts of this kind should be able to show you what is visible every night of the year at any time of night. You can mark your favorite objects on the star chart. You will always know whether they are visible or not and, if visible, where they are in the night sky.
Our Star and Planet Locator Map is 8.5" x 8.5" and comes with a booklet that contains a wealth of information, including:
- the many different ways you can use a planisphere
- the brightness and distance in light years of the most visible stars
- how and where to find the planets
- and there's even a pronunciation guide for Arabic and Latin names of the stars and constellations!