[LEAPSECS] telescopes and observatories

Rob Seaman seaman at noao.edu
Thu Jan 12 15:29:33 EST 2012


Tony Finch wrote:


> Rob Seaman wrote:

>

>> See rather: http://ucolick.org/~sla/leapsecs/timescales.html

>>

>> The only coherent astronomical usage of the term would be "mean solar time on the prime meridian".

>

> Thus once again, the meaning of GMT was ambiguous, as this abbreviation was used for both Greenwich mean solar time, which closely followed the variations in the rotation of the Earth and was the argument in the tables in the navigational almanacs, and for coordinated universal time, which was based on International Atomic Time (TAI).


And these are currently the same thing for most purposes.

It is action by the ITU which would render GMT ambiguous beyond the level of a second.

How many time scales must die to circumvent an occasional leap second?

Rob



More information about the LEAPSECS mailing list