Sky Basics: Poles, Polaris, and Landmarks

Vocabulary flashcards covering celestial poles, Polaris, circumpolar stars, and common sky landmarks (Big Dipper) with practical location cues.

Polaris (North Star)

The star nearest the North Celestial Pole; serves as a navigational reference; its altitude above the horizon roughly equals the observer’s latitude.

North Celestial Pole

The point in the sky directly above Earth's north axis; around which stars appear to rotate.

Circumpolar Stars

Stars that, for a given latitude, never set because they stay above the horizon as they circle the celestial pole.

Big Dipper

A bright asterism with a curved bowl; used as a landmark to find Polaris; its two outer stars point toward Polaris.

Finding Polaris with the Big Dipper

Trace a line through the two stars at the end of the Big Dipper's bowl to locate Polaris.

Polaris altitude ≈ observer latitude

Polaris's altitude above the northern horizon is approximately equal to the observer’s latitude.

Baton Rouge example

In Baton Rouge (about 30° N), Polaris is roughly 30° above the northern horizon.

Equator sky perspective

At the equator, the north celestial pole lies on the horizon; Polaris sits on the horizon and many stars rise in the east and set in the west.

North Pole sky perspective

At the North Pole, the North Celestial Pole is at the zenith; stars rotate around it and do not rise or set.

Polaris brightness

Polaris is not exceptionally bright; it is an average-brightness star visible in the night sky.