LIBRATION

Pronunciation (US):

(GB):

IPA (US):

 Dictionary entry overview: What does libration mean? 

• LIBRATION (noun)
  The noun LIBRATION has 1 sense:

1. (astronomy) a real or apparent slow oscillation of a moon or satellite

  Familiarity information: LIBRATION used as a noun is very rare.

 Dictionary entry details 

• LIBRATION (noun)

Sense 1

Meaning:

(astronomy) a real or apparent slow oscillation of a moon or satellite

Classified under:

Nouns denoting natural processes

Context example:

the libration of the moon

Hypernyms ("libration" is a kind of...):

variation ((astronomy) any perturbation of the mean motion or orbit of a planet or satellite (especially a perturbation of the earth's moon))

oscillation (the process of oscillating between states)

Domain category:

astronomy; uranology (the branch of physics that studies celestial bodies and the universe as a whole)

Derivation:

librate (vibrate before coming to a total rest)

 Context examples 

In 2007, radar observations made from Earth revealed small shifts in the spin of Mercury, called librations, that proved some of Mercury’s core must be liquid-molten metal.

(A Closer Look at Mercury’s Spin and Gravity Reveals the Planet’s Inner Solid Core, NASA)

They suggest that other models could be developed to explain the moon's observed libration, and that further measurements by Cassini could help determine which model is most likely to be correct.

(Saturn Moon May Hide a 'Fossil' Core or an Ocean, NASA)

This effect is called libration, and Earth's moon does it as well.

(Saturn Moon May Hide a 'Fossil' Core or an Ocean, NASA)