ABSTRACT
Two American astronomers, Humason and Zwicky, of Mount Wilson Observatory, in California, have recently reported a hunt for faint blue stars in two areas of the heavens. One was in the neighbourhood of the Hyades in the constellation of the Bull, where stars are very thick. The other was in the constellation Coma Berenices, as far away as possible from the Milky Way. Most of the blue stars in the Hyades shared the motion of Aldebaran and the other bright stars of this cluster. So they must be very much dimmer. It turns out that they belong to the group of stars called White Dwarfs, which are extraordinarily dense. In the direction of the Milky Way there is so much dust between the stars that one can usually only photograph stars, however bright, a few thousand light years away. At right angles to the Milky Way one can see out into space beyond it.
