In a nut-shell, for you, whether the solar system, obeying the equations of celestial mechanics, is or is not a computer somehow depends on whether or not it is used to compute something. This is, to put it mildly, to make the computational status of the whole universe answerable to the intentions of one small stratum of one small planet. A short essay prompted by your question. I hope I have succeeded, at least in part. Think 2, June 1993, pp.
Words Lie in Our Way.