On 2010-11-04 21:46, Zefram wrote:
.................................... There is a recent near-renaming that shows the way: the modern form of Sidereal Time is known as Earth Rotation Angle. This name is accurate in some important ways: it's specific to Earth, and it's not time at all but an angular measure.
To be precise, Earth Rotation Angle exists _in addition_ to a modern form of Greenwich mean sidereal time, whose definition uses both ERA and TT. See for example p 16 of [http://www.usno.navy.mil/USNO/astronomical-applications /publications/Circular_179.pdf]. The new name denotes a new concept, the old concept has retained its name. Michael Deckers. _______________________________________________ LEAPSECS mailing list LEAPSECS@leapsecond.com http://six.pairlist.net/mailman/listinfo/leapsecs
