书城公版ABC's of Science
20818000000005

第5章

ACROSS THE DIVIDE

1.

Crossing the divide (Abyss) we encounter other systems of about 25,000,000,000, or the first magnitude. Our most powerful glass reaches the 16th.

Magnitude is very uneven and irregular, and beyond this there is no end.

2.

Many constellations have more than one sun, while others are double, quadruple, and multiple. It is estimated a brilliant star, and can be seen; of these over a million have been catalogued and only about 25whose distance have been measured.