def julian_century(jd_local):
    """Returns the Julian Century with Julian Day, julian_local."""
    days_century = 2451545
    day_per_century = 36525
    for i in range(2451545, 0, -36525):
        if jd_local < i:
            days_century = i - day_per_century
        else:
            break
    julian_cent = (jd_local - days_century) / day_per_century
    return julian_cent
