Universal Time (UT) is a timescale based on the rotation of the Earth. It is a modern continuation of the Greenwich Mean Time (GMT), i.e. the mean solar time on the meridian? of Greenwich, England, which is the conventional 0-meridian for geographic longitude. |
Universal Time (UT) is a timescale based on the rotation of the Earth. It is a modern continuation of the Greenwich Mean Time (GMT), i.e. the mean solar time on the meridian? of Greenwich, England, which is the conventional 0-meridian for geographic longitude. |
Coordinated Universal Time: this is civil clock time. It is measured with atomic clocks, but always kept within 0.9 seconds from UT1. Because UT slows down with respect to TAI, a leap second must be applied about once every one or two years. This is the responsibility of the IERS: see http://www.iers.org/iers/publications/bulletins/bull_c/ for announcements; and |
Coordinated Universal Time: this is civil clock time. It is measured with atomic clocks, but always kept within 0.9 seconds from UT1. Because UT slows down with respect to TAI, a leap second must be applied about once every one or two years. This is the responsibility of the IERS: see http://www.iers.org/iers/publications/bulletins/bull_c/ for announcements; and |