The Astrology of Space - Matrix Software

The Astrology of Space
Chapter 8: The Kinds of Stars
Double Stars
Not all stars stand alone as solitary beacons in space.
A surprising number of stars are double, made up of
two separate components, which may be either
perfect twins or decidedly unequal in size and
luminosity. Double stars, whose components are
intrinsically associated and are in motion round a
common center of gravity, are known as binaries.
Optical doubles, in which the appearance is due to a
chance alignment with one star almost behind the
other, are much less common.
For a long time astronomers thought all double stars
were a result of such chance alignment. The first
discovery of a double star with a telescope occurred
in 1650, although both Arabs and North American
Indians have used the double stars Mizar and Alcor
as a test of keen eyesight for centuries.
The optical doubles are often divided into two types:
equal doubles and unequal doubles. In the equal
doubles, both components are of similar magnitude
(example: Gamma Aries), while in the unequal
doubles, the magnitudes as well as the colors of the
two stars will differ. (example: Beta Cygni). Again:
optical doubles result when two stars appear close to
one another through chance alignment rather than
gravitational interdependence. One star may be at a
much greater distance from the Earth than the other.
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