Beyond Our Galaxy: The Great Big Universe Out There - Celestron NexStar 90 MAK Instruction Manual

TheSkyX First Light Edition User Guide
you look at the Milky Way, you're looking at a
section of one of these spiral arms (galaxies come in
a variety of shapes and sizes, from spherical to
irregular – more on this later).
An unfortunate fact of modern life is that the Milky
Way is too faint to be seen from within cities and
most of their suburbs. You need to be far from city
lights and any other source of light pollution to
appreciate how extraordinarily beautiful it is.
TheSkyX can display the Milky Way at various
levels of brightness, simulating what you might see
from the outskirts of a small town or an isolated
mountain peak. Astronomers have come up with
the very cool-sounding term isophote to describe
regions of equal brightness in the Milky Way.
Beyond Our Galaxy: The Great Big Universe
Out There
About a hundred years ago astronomers believed
that our galaxy, the Milky Way, contained pretty
much everything in the universe. But as telescopes
became larger and more powerful, it became clear
that there are other galaxies beyond the Milky Way
– lots of them, in fact. According to the latest
estimates, there are some fifty to one hundred
billion galaxies in our universe comparable in size
to the Milky Way.
Our galaxy is also surrounded by a halo of some
hundred and fifty star clusters.
contain hundreds of thousands to millions of stars
arranged in relatively compact, spherical shapes.
These globular clusters are made up mostly of
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These clusters
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