code: func julianDayToTime(jd int) time.Time {
  	var f int
  
  	if jd < gregorianDay {
  		f = jd + 1401
  	} else {
  		f = jd + 1401 + (((4*jd+274277)/146097)*3)/4 - 38
  	}
  
  	e := 4*f + 3
  	g := (e % 1461) / 4
  	h := 5*g + 2
  	day := (h%153)/5 + 1
  	month := (h/153+2)%12 + 1
  	year := (e / 1461) - 4716 + (12+2-month)/12
  
  	return time.Date(year, time.Month(month), day, 0, 0, 0, 0, time.UTC)
  }
docs: // JulianDayToTime returns the correcponding UTC date for a Julian Day Number.
  // The algorithm is taken from https://en.wikipedia.org/wiki/Julian_day.