Re: Date and time on Cindu: yearly update

What is 141? Mine is a US Navy Julian Date Converter... Am I missing
something? (:
Eugene

On Tue, May 20, 2008 at 8:15 PM, Mark J. Reed <markjreed@...> wrote:

> Sorry, I know it's clear in the context of astronomy.  In the context
> of calendar conversions, though, I think you can see where it might be
> confusing.  Today's "Julian date" could be any of May 7, 2008;
> 2,454,607; or the #1 hit for "Julian date" on Google: 141. :)
>
>
>
> On 5/21/08, Michael Poxon <mike@...> wrote:
> > Yes, but to an astronomer, "Julian Date" only ever means one thing, and
> as
> > you say, the usual practice is simply to write "JD", the interpretation
> > always being clear from the context. In my field (variable stars) you use
> > nothing else. And in fact, GMAT itself is now falling out of favour,
> being
> > replaced by UT (Universal Time, which starts at midnight).
> > Mike
> > ----- Original Message -----
> > From: "Mark J. Reed" <markjreed@...>
> > To: <CONLANG@...>
> > Sent: Monday, May 19, 2008 3:41 AM
> > Subject: Re: Date and time on Cindu: yearly update
> >
> >
> >
> >> Gah.  Unfortunately, "Julian Date" is an overloaded term which can
> >> also mean simply the date in the Julian calendar and is also often
> >> used (incorrectly) to mean the day number within the current year.  So
> >> while astronomers distinguish between "Julian Day" (integral value)
> >> and "Julian Date" (value with fraction indicating time of day), I just
> >> lump them both togther as "Julian Day" or, better yet, the unexpanded
> >> acronym "JD", to avoid confusion.  Another possibility I've seen used,
> >> along the GMAT lines, is "Julian Astronomical Day/Date" or "JAD".
> >
> >>
> >>
> >> --
> >> Mark J. Reed <markjreed@...>
> >>
> >>
> >> --
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> >>
> >
>
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>
> Mark J. Reed <markjreed@...>
>

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