function epoch2jd, epoch
;+
; NAME:
;	EPOCH2JD
;
;
; PURPOSE:
;	Convert SMEI epoch to Julian Day.
;
;
; CATEGORY:
;	Utils
;
;
; CALLING SEQUENCE:
;	jd = epoch2jd(epoch)
;
;
; INPUTS:
;	epoch	numeric	The SMEI epoch(s) to convert.
;
;
; OUTPUTS:
;	jd	double	The julian day number(s) of the epoch(s)
;
;
; MODIFICATION HISTORY:
;	Original: 25/3/03; SJT
;-

jd0 = doy2jd([2000, 1, 12])     ; Epoch is noon on 1/1/00

return, jd0 + double(epoch)/8.64d4

end