AAAA Observing Reports
An Introduction to
Late Summer
Deep Sky Objects
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The purpose of this program is to provide a starting point for new astronomers to begin their exploration
of the sky. On a nice summer evening out under the stars, and with the help a
good star chart, you
should be able to find easily each of the objects mentioned on this page. The constellations and objects were chosen
to be both easy to find and representative of each of the major types of deep sky objects: a globular cluster,
a planetary nebula, a galaxy, open clusters, and a diffuse nebula. There is also one beautiful double star included.
As you find each object, use an observing form to log your observations. We have
provided an official AAAA
Observing Log in PDF format for your convenience. To begin, find the
constellation with your naked eye, then look for the object with binoculars. Finally, use a telescope to view the
object up close. Enlist the help of your friends as necessary.
HERCULES
Almost overhead at the arrival of night in late summer are the constellations of Hercules and Lyra. Hercules
is a large constellation whose brightest stars are relatively faint, so a good, dark sky is needed to see the complete
outline of the heroic figure. Lyra, on the other hand, is small, but contains the bright star Vega as its brightest
member. The objects of interest in this region are relatively close to us in space.
M13 This famous globular cluster is large and bright enough to be seen
with the naked eye on good nights. It is about 12-15' in diameter, rather easily resolved across the center, and
is seen to be somewhat ragged in appearance. There are long strings of stars curving away from the center, and
a curious propeller shaped area at its southwest edge which seems almost devoid of stars.
LYRA
M57 The Ring Nebula. One of the jewels in the sky, the Ring Nebula is
bright and easily found. The ring shape is easily seen in almost any size instrument. It is slightly elongated
ENE-WSW, and has a star just off its eastern edge. This object handles magnification very well, and at 15th magnitude,
its central star is only well seen in large amateur instruments.
SCORPIUS
The constellation of Scorpius is one of the few constellations which actually
resembles what it is supposed to represent, a scorpion. This large and sprawling area contains many open and globular
clusters, as well as a wealth of nebulosity, particularly in the region of its brightest star, Antares. As large
as it is, Scorpius actually used to be much larger. In ancient times, the brightest stars of the constellation
Libra used to be considered part of Scorpius, representing the scorpion's claws. There are several open clusters
in Scorpius which are of particular interest.
M-6 The Butterfly Cluster. This fine open cluster is large, about 25'
in diameter and contains over a hundred bright and relatively bright stars. It is called the Butterfly Cluster
because some observers see the shape of a butterfly formed by the stars. This cluster is visible to the naked eye
as a faint patch of light.
M-7 This beautiful open cluster is almost a degree in diameter, so either
very low powers or binoculars should be used to optimally view it. This loosely concentrated cluster is easily
visible to the naked eye.
SAGITTARIUS
The constellation of Sagittarius lies along the southern portion of the Milky Way, and within its boundaries
lies the very heart of our galaxy. Because of this, when we look in this region, we should expect to find many
open clusters, gaseous nebulae, planetary nebulae, and globular clusters which swarm around the galaxy's center.
And this is exactly what we find here. Within Sagittarius' borders are found some of the finest examples of each
of these object types. There are many Messier objects in this area, of which I will list only a few, along with
some lesser known objects from the Herschel list. This region is worthy of several night's of investigation, not
only with a telescope, but also with binoculars. If you haven't started on your Binocular Messier Certificate yet,
this is an excellent region with which to begin, as many of the objects are bright and easily seen.
M-8 The Lagoon Nebula. With the possible
exception of the Great Orion Nebula (M-42), this is probably the finest cluster and nebula combination in the heavens.
A large and loosely scattered open cluster is seen in juxtaposition with a large and swirling mist of nebulosity.
Many dark regions can be seen in looping patterns which are highlighted by the brighter regions. This object is
easily seen in finder scopes, binoculars, and with the naked eye.
M-20 The Trifid Nebula. Only a short distance north of M-8, this object
is rather easily found, but is considerably fainter than that object. A double star is seen surrounded by a mostly
circular patch of light. This patch of light is divided into three separate regions by dark lanes which intersect
near its center. On a good night, a fainter region of reflection nebulosity of almost equal size as the main portion
can be seen to the north.
ANDROMEDA
Andromeda lies away from our galaxy's plane, and lets us see the inhabitants of intergalactic space.
M-31, 32, & 110 The Great Galaxy in Andromeda and its companions.
M-31 is the closest large spiral galaxy to our own Milky Way galaxy, and therefore presents us with a wealth of
details. Numerous dust lanes are evident, and large telescopes can even identify individual members of its system
of globular clusters. I find the best view of this galaxy trio to be through large binoculars. At this magnification,
the complete extent of the main galaxy can be seen, and the fuzz, star-like M-32 and the elliptical M- 110 can
be glimpsed quite easily in the same field of view.
Gamma Andromedae One of the prettiest
double stars in the sky. It is easily split, and shows a golden-orange primary and a fine blue companion. A must
see.
(Excerpts from Constellation of the Month articles by Rick Raasch.)
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