Altitude-Azimuth coordinates

Azimuth measures along the horizon in degrees. When combined with altitude, "Altitude-Azimuth coordinates" uniquely specify a given point with respect to an observer's horizon at an indicated time.

Test your understanding:

• Do any two different locations in the sky have the same pair of altitude-azimuth coordinates?
• Do altitude-azimuth coordinates vary with location? That is, will two astronomers who are observing the same planet or star at the same time, but who are located many miles apart, see it at different altitude-azimuth coordinates?

Altitude-Azimuth coordinates are used with many telescope mounts.

Try this:

• Use a protractor outdoors to estimate the altitude of Polaris, or to measure degrees of azimuth along the horizon, starting from due north.