Julian Date and UbiSol

[John Hall]

(Julian Day). The result for 2003/04/26 seems to be at odds with other 
calculators.

UbiSol = JD 21478.5
Meeus and others = JD 2452755.5

You and other respected references state this date is calculated from 
January the 1st 4173 BC. Meeus in his first edition of Astronomical 
Algorithms on page 59 states this is calculated from '....... the 
beginning of the year -4712'

Can somebody please help me with an explanation ?

Confused of Tasmania
41.5 South   147.1 East

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