Observing · Constellations
Declination
Say it: dek-lih-NAY-shun IPA: /ˌdɛklɪˈneɪʃən/ noun
Declination: The angle of a celestial object north or south of the celestial equator.
Project Earth's latitude lines onto the sky and you get declination. With right ascension, it fixes an object's place on a star map regardless of where you stand.
- Example
- A star with a declination of 60 degrees north never sets for most observers in Europe.
- Why astronomers use it
- It is one half of the standard coordinates astronomers use to find anything in the sky.
- Tiny cosmic connection
- Compass declination is something else: the difference between magnetic north and true north.
Observatory Observing Constellations
Where to check it
- NASA Science: Universe glossary (opens in a new tab)
- NASA Hubble glossary (opens in a new tab)
- NASA: Basics of Space Flight glossary (opens in a new tab)
- Wikipedia: Declination (opens in a new tab)
Written for Cool Moon Facts in its own words; the sources cover the same idea in more depth.