266 Grimoire for the Apprentice Wizard
(This view is
in Spring)
GREATBEARLITTLEBEARmain disk in the shape of a spiral with two or more
arms and a large central bulge. Others are barred, ellip-
tical, egg-shaped and even irregular, but all are be-
lieved to represent an evolutionary continuum lead-
ing from a huge quasar to a spiral form. Galaxies are
gravitationally bound into clusters containing hun-
dreds or thousands of members. Our own Milky Way
is a member of the Virgo Cluster.The size of individual galaxies with respect to
the distance between them makes galaxies rela-
tively much closer together than are the stars
within them. It is therefore common for galaxies
to collide without the stars within them collid-
ing. One of the observed effects of galactic colli-
sions is to increase the production of new stars
within both galaxies due to the interaction of
huge clouds of interstellar gas and dust. Slowly
moving and rotating galaxies collide over peri-
ods of millions of years. —Bruce Bryson,
“Quarks to Quasars: Powers of Ten”Star systems are formed within galaxies as whirl-
pools of cosmic dust and debris coalesce, gathering
more mass together until the nucleus ignites. Smaller
eddies of spinning vortices within these accretion
disks eventually become planets. If they are big
enough, they may even form into multiple stars, rather
than just one. Our Sun is just an average-sized star.
Tiny white dwarfs may be no larger than the Earth,
while Antares (the red giant in the heart of Scorpio) is
bigger than the orbit of Mars.
Stars go through multiple generations, form-
ing initially out of pure hydrogen, which they con-
vert to helium. When this process is completed,
they explode in a supernova, which creates far
heavier elements which are then scattered out into
space. Out of those heavier elements, the next gen-
eration of stars form, this time with planets.
But all the stars, planets, dust and other matter
in the universe accounts for only 4.4% of its mass!
According to astronomers, 23% is bizarre “dark mat-
ter,” and 73% is some unknown “dark energy.”Lesson 8. The Constellations
On a clear moonless night, we can see about 2,000
stars. The Roman astronomer Claudius Ptolemy of
Alexandria (85-165 CE) grouped 1,022 of these stars
into 48 pictures called constellations (“stars to-
gether”). Although Ptolemy’s Almagest, completed in
129 CE, does not, of course, include those stars which
can only be seen from the southern hemisphere, it
forms the basis for the 88 constellations now officially
listed by the International Astronomical Union.
These figures are purely a human invention as
seen from Earth; the stars in them are not actually
associated with each other in any way, and are really
many lights years apart. From another star system they
would look totally different. To see these star-pictures
yourself, all you need to do is learn how to “connect
the dots.” However, the diagrams shown in most books
don’t make any sense. The ones I am adapting here
were mostly worked out by H.A. Rey, in a wonderful
book called Find the Constellations (1954).The Circumpolar Constellations
The six Constellations that circle Polaris, the
North Star, are called the North Circumpolar Constel-
lations, and they are visible from the northern hemi-
sphere at all times of the year. These are Ursa Minor
(Little Bear), Ursa Major (Great Bear), Draco (Dragon),
Cepheus (King) and Cassiopeia (Queen), and
Cameleopardus (Giraffe). If you are star-gazing in the
northern hemisphere, the first thing to do is to locate
the Big Dipper in the constellation of Ursa Major. To
find Polaris, and thus true Celestial North, trace a line
through the two “pointer stars” at the end of the
Dipper’s bowl. Once you’ve found the Big Dipper,
you can use it as a key to locate a number of other
bright stars and their Constellations. Here is a dia-
gram. Compare this with the night sky, and memorize
these key figures:20 03Corrected pages PM.p65 13 3/25/2004, 2:27 PM