User`s guide

Appearance of the Sky 53
Number of Labels: A slider allows you to
change the number of objects that are
labeled onscreen for each database. If the
slider is near the left edge, only the
brightest members of the database will be
labeled. As you move the slider farther to
the right, dimmer objects will be labeled as
well.
Some other label options appear only for
certain databases. These options are listed
below:
Label by Magnitude Slider: This is an
option for planets/moons, comets,
asteroids, and artificial satellites (when
open, it replaces the “Number of Labels”
slider). By default, Starry Night will not
label an object if it is too dim to appear on
screen. You can change this option. For
example, you may wish to know the
position of all the planets. Pluto and
Neptune are generally too dim to be seen,
but by selecting this option, you will still
be able to see where they are in the sky.
Star Label Options: The “Show” dropbox
in the Star Options dialog box allows you
to label a star by its common name,
catalogue number, Bayer letter, or
Flamsteed number. Most common names
are thousands of years old and have an
Arabic origin. The classification scheme
for Bayer letters and Flamsteed numbers is
discussed in “Bayer
” on page 91. You can
also choose to show the magnitude of
stars, an option that is particularly useful
for printed charts, as you will often use the
brightness of an object to help you
determine if you are looking at the right
object.
Constellations
People have always joined together
patterns of stars to create images in the
night sky. The most well known of these
are those that have been handed down to
us from the Arabs, Greeks, and Romans.
Astronomers use these ancient
constellations as a guide to map the stars
into various regions. Today the
International Astronomical Union
recognizes 88 unique constellations, which
together cover the entire sky. Many of the
best-known figures in the sky, such as the
Big Dipper and the Summer Triangle, are
not formal constellations, but are known as
asterisms. Starry Night has many options
for drawing the constellations. All
constellation options can be accessed by
expanding the “Constellations” layer in
the Options pane.
Auto Identify: Checking this box will
highlight the constellation which is at the
centre of the screen. If you scroll around
the screen, the highlighted constellation
will change.