def lightabbr_low(jde):
    ''' compute light abberation use less accurate method
     compensate light aberration, A&A p152, constant of aberration
     k = 20.49552"

    the error can be up to 0.01"

    '''
    t = (jde - J2000) / 36525.0
    t2 = t * t
    t3 = t2 * t

    # mean anomaly of the Sun
    M = 357.52910 + 35999.0503 * t - 0.0001559 * t2 - 0.00000048 * t3
    # the eccentricity of Earth's orbit
    e = 0.016708617 - 0.000042037 * t - 0.0000001236 * t2
    # Sun's equation of center
    C = ((1.9146 - 0.004817 * t - 0.000014 * t2) * sin(math.radians(M))
         + (0.019993 - 0.000101 * t) * sin(math.radians(2 * M))
         + 0.00029 * sin(math.radians(3 * M)))
    # true anomaly
    v = M + C
    # Sun's distance from the Earth, in AU
    #R = (1.000001018 * (1 - e * e)) / (1 + e * cos(math.radians(v)))
    # finally, the aberration in radians
    labbr = (math.radians(20.49552 / 3600.0)
            * (1 + e * math.cos(math.radians(v))) / -1.000001018)
    return labbr
 compute light abberation use less accurate method
     compensate light aberration, A&A p152, constant of aberration
     k = 20.49552"

    the error can be up to 0.01"

    
aa.py