Declination

Definition

Declination is the angular distance of a celestial object north or south of the celestial equator. It is measured in degrees, with positive values indicating north and negative values indicating south.

5 Must Know Facts For Your Next Test

1. Declination is one of the two coordinates used in the equatorial coordinate system to specify the position of an object in the sky.
2. It ranges from +90 degrees at the celestial north pole to -90 degrees at the celestial south pole.
3. Declination is analogous to latitude on Earth but applies to celestial objects.
4. A star with a declination of 0 degrees lies on the celestial equator.
5. To find a star's declination, astronomers use instruments like telescopes equipped with setting circles.

Review Questions

• What does a declination of +45 degrees indicate about the position of a celestial object?
• How does declination compare to latitude on Earth?
• Why is declination important for locating stars and other celestial objects?

Related terms

Right Ascension:

The angular distance measured eastward along the celestial equator from the vernal equinox.

Celestial Equator:

An imaginary circle created by extending Earth's equator into space.

Latitude:

The measurement of distance north or south of Earth's equator, similar to declination but for terrestrial locations.