[fitsbits] Re: leap second alert

[Maren Purves]

Paul Schlyter wrote:
> William Thompson <thompson at orpheus.nascom.nasa.gov> wrote:
> >         (rest deleted)
> > Personally, I would expect UT to mean either UTC or UT1.  This is one reason
> > why letting UTC drift relative to UT1 is so troubling.
> 
> If one requires an accuracy large enough that the difference between
> UT1 and UTC matters, then one should not just write "UT" (or "GMT"),
> but instead explicitly specify if UTC or UT1 is used.
> 
> > The computer industry tends to use the acronym GMT as a synonym for UTC, but
> > there's currently no exact recognized definition for GMT.
> 
> There have been several different definitions of GMT.  Earlier, GMT was
> often considered equal to UT1.  Thus, the term "GMT" should be used only
> when the difference between UTC and UT1 doesn't matter.

As long as they don't drift apart by too much, for both.
If they are 20 minutes apart I'd expect it to matter in a lot
moare applications, astronomical or not, than it does as long
as the difference is under a second.

Maren Purves, UKIRT
(but: what how much does this still have to do with FITS?)