- a real or apparent oscillatory motion, especially of the moon.
Origin of libration
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for libration
For other worlds, we usually have to rely on other data: fluctuations in gravity, or the gentle rocking motion known as libration.
The authors of the new study used data from the Cassini probe orbiting Saturn to measure the libration of Mimas.
A list of some of the principal astronomical researches of Lagrange and Laplace:—Libration of the moon.
The one on the left illustrates the manner in which the libration in longitude is made apparent.
The last of Galileo's great astronomical discoveries related to the libration of the moon.Great Astronomers
R. S. Ball
One more astronomical discovery also he was to make—that of the moon's libration.
We'd show enough, however, to make it damned impressive, and explain it by libration of the satellite.Question of Comfort
- the act or an instance of oscillating
- a real or apparent oscillation of the moon enabling approximately 59 per cent of the surface to be visible from the earth over a period of time
C17: from Latin librātus, from librāre to balance
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012