function solar_time,time,lon

;-------------------------------------------------------------------
; Routine calculates the local solar time (LST) 
;
; Input:
;   time.....time of day, hours GMT
;   lon......longitude, degrees (0-360)
;
; Output:
;   LST......local solar time, hours
;
; Source: Mark Hervig
;-------------------------------------------------------------------

   barg = time * 60. + lon * 4.
   
   LST  = (barg mod 1440.) / 60.

;- done

   return,LST
   
   end