Universal Time (UT1)

Acronym: UT1
In French: Temps universel

UT1 is the rotation angle about the Earth pole.

UT1 can be regarded as a time determined by the rotation of the Earth. It is distributed by the IERS as the difference UT1-UTC in IERS Bulletins A and B and in other data files.

Universal Time (UT) is counted from 0 hours at midnight. The unit of duration is the mean solar day.

UT0 is the rotational time of a particular place of observation.

UT1 is computed by correcting UT0 for the effect of polar motion on the longitude of the observing site.

Related terms:

• Coordinated Universal Time

Related links:

• Earth orientation data