Page:Astronomy for Everybody.djvu/348

Alpha Centauri. The distance of the stars whose parallaxes are too small to be measured is a matter of judgment rather than calculation. The probability seems to be that at least the brighter stars are scattered through space with some approach to uniformity. If this is the case, many of the fainter telescopic stars, perhaps the large majority of the smallest ones found on photographs of the heavens, must be more than one thousand times the distance of Alpha Centauri. The light by which their presence is made known to us must have been on its way to our system during the whole period of human history.