AstroMedia: The star clock (Nocturnal)

AstroMedia: The Star Clock (Nocturnal)

Using Polaris and the Big Dipper to tell the time
With the help of the sidereal clock, the local time (= solar time) can be read at night from the position of the constellation Big Dipper in relation to the pole star. The device consists of two rotating discs, one above the other, with a pointer and a hole in the center. The date is set on the lower disk. Afterwards the polar star is aimed through the hole, at the same time the pointer is set to the pole pointer of the Big Dipper. In this way, the time can be read on the upper disk. If it is too dark, you can even find the time by scanning it with your fingertips.

For teachers and students
The star clock is easy to build and is ideal as teaching material at secondary schools. Like all other astro materials, it can also be used for other group and project work on astronomy and physics.

This is what else you will need for assembly

a solid, flat work surface

a sharp cutter knife

a good all-purpose glue

some fine sandpaper

a pair of scissors