planisphere
/ˈplænɪsfɪr/
noun
- A circular star chart with an adjustable overlay that shows which stars and constellations are visible at a given time and place.
- By turning the dial on the planisphere, she could see what constellations would appear at midnight.
- The astronomy club gave each member a planisphere to help them learn the night sky.
- He used a planisphere to find the North Star on his camping trip.