Astronomical ruler

The astronomical ruler will come in handy if you like celestial navigation with a sextant or just stargazing.

Star identifier astronomical ruler, and for sextant astronomical navigation purists the Rude pattern star finder from Weems & Plath.

For celestial navigation, you may also need:

• nautical ephemerides including the Dieumegard and Bataille tables and the HO-249 tables or others...
• sextant, artificial horizon
• astronomical calculator
• marine chronometer
• astronomical ruler
• astronomy course books and manipulation of a sextant
• professional astronomy books