Re: Date and time on Cindu: yearly update

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@...>
>>
>>
>> --
>> No virus found in this incoming message.
>> Checked by AVG.
>> Version: 7.5.524 / Virus Database: 269.23.20/1453 - Release Date:
>> 18/05/2008 09:31
>>
>>
>
--
Sent from Gmail for mobile | mobile.google.com

Mark J. Reed <markjreed@...>

Reply