Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!hp-pcd!hpcvra.cv.hp.com!everett
From: everett@hpcvra.cv.hp.com. (Everett Kaser)
Newsgroups: comp.binaries.ibm.pc.d
Subject: Re: (Astronomical) Julian Date Source Wanted
Message-ID: <40790007@hpcvra.cv.hp.com.>
Date: 16 Apr 91 17:27:04 GMT
References: <9873.2808dac2@ohstpy.mps.ohio-state.edu>
Organization: Hewlett-Packard Co., Corvallis, OR, USA
Lines: 24

>  everett@hpcvra.cv.hp.com. (Everett Kaser) writes:
>>Just out of curiousity, what's the difference between Astronomical and 
>>USGovernment Julian dates?
>
>Strictly speaking the astronomical quantity is the Julian day number,
>which is the number of ephemieris days that have elapsed at the
>previous 12h ET since 12h ET on 1 Jan 4713 BCE.
>
>You'll have to specify what you mean by US Govt Julian dates.  It is
>common to count the days from 1 Jan 1900, without tying them to noon,
>or to Zulu time.  Some even confuse day of year with Julian date.
>Jim Roberts	roberts@stsci.edu	scivax::roberts

I'm giving up, I'm SO confused.  The original poster had mentioned USGov'mt
Julian days, which was what I was unfamiliar with.  Now, you've confused
me about Julian days completely.  I thought Julian days were measured from
sometime in the 1500's AD.  I've never heard of 'BCE', and I have no idea
what happened 4713 years ago (or more) that 'BCE' years would be based on.

Oh well.

Everett Kaser                   Hewlett-Packard Company
...hplabs!hp-pcd!everett        work: (503) 750-3569   Corvallis, Oregon
everett%hpcvra@hplabs.hp.com    home: (503) 928-5259   Albany, Oregon