[ntp:questions] Re: Extracted fom comp.risks - What Time Is It?

Drk Ryan ryandrk at hotmail.com
Sat Aug 23 10:35:06 UTC 2003

Two questions regarding the Guardian article on timescales:

"The first of these "leap seconds" was introduced in 1972, mainly as a
favour to astronomers and others who still relied on the old-style
celestial time. A further 31 leap seconds have been added since, most
recently on December 31 1998."

However, according the NIST Time Scale Data Archive's Leap second and
UT1-UTC information page there has been only 22 leap seconds added
since 1972.

Is the Guardian article incorrect?

"It includes the leap seconds added until the GPS clock was set in
1980, but has ignored those added since. This means GPS time is now
running 13 seconds ahead of coordinated universal time - which
includes all added leap seconds and to which most clocks on Earth are
set - but is some 19 seconds behind international atomic time, which
is based on atomic clocks and ignores leap seconds."

Should GPS time not be running 13 seconds *behind* UTC if it has not
implemented leap seconds since 1980?

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