def _long_prec(T):
    """
    From SOFA (2010) - IERS 2003 conventions
    
    :param T: Julian centuries from 2000.0 in TDB (~TT for this function)
    :type T: float or array-like
    
    :returns: General accumulated precession in longitude in radians
    """
    return (0.024381750 + 0.00000538691*T)*T