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Re: Epoch time of Keplerian elements.



HEYLER YESID LEDEZMA LEUDO wrote:
> Hi.        
>    
>   Excuse me for my defective English.

No trouble at all ...
>    
>   Keplerian Elements is a Julian date or is a Gregorian date?. 
>    

Gregorian.

The following is from http://celestrak.com/columns/v04n03/#FAQ02

(H)ow is the epoch time format interpreted? This question is best 
answered by using an example. An epoch of 98001.00000000 corresponds to 
0000 UT on 1998 January 01—in other words, midnight between 1997 
December 31 and 1998 January 01. An epoch of 98000.00000000 would 
actually correspond to the beginning of 1997 December 31—strange as that 
might seem. Note that the epoch day starts at UT midnight (not noon) and 
that all times are measured mean solar rather than sidereal time units 
(the answer to our third question).


-Joe KM1P

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