|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 1
|
Crab Nebula
|
05:34.3
|
+22° 01
|
4000
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
6
|
8.4
|
Supernova Remnant
|
Taurus
( TAU )
|
135
|
|
Discovered in 1731, M1,
the "Crab" nebula is the remnant of the supernova of July 4,
1054AD. (A supernova is an exploding star). The gases are expanding out at a
rate of over 600 miles/second, making the cloud 6 light years across. One
of the most scrutinized objects in the sky, M1 is one of the strongest
radio and X-ray sources. M1 is also home to one of the fastest
"pulsars" known, emitting energy bursts at nearly 30 times a
second, while being only a few miles in diameter.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 2
|
|
21:33.3
|
-00° 50
|
37000
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
12.9'
|
6.5
|
Globular Cluster
|
Aquarius
( AQR )
|
255
|
|
M2 is a "fine"
globular cluster, it's 6th magnitude intensity
making it an easy object for binoculars and small telescopes. Containing
over 100,000 stars, M2 consists of primarily 14th and 15th magnitude
objects. (By comparison, were the Sun at that
distance it would be only 20th magnitude).
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 3
|
|
13:42.0
|
+28° 24
|
35000
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
16.2
|
6.4
|
Globular Cluster
|
Canes Venatici
( CVN )
|
110
|
|
M3 is one of more
heavily studied globular clusters due to its position in the galaxy, putting
it far from interstellar absorbtion. More than 200 variable stars have been
observed out of a total of near 50,000. Being one of the brightest
clusters, M3 is regarded as one of the most striking in the sky. A 6-inch
scope will begin to reveal hundreds of its magnitude 11 stars, while larger
instruments may show arms or branches radiating from the sides.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 4
|
|
16:23.3
|
-26° 31
|
14000
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
26.3'
|
5.9
|
Globular Cluster
|
Scorpius
( SCO )
|
336
|
|
M4 is one of the largest
and nearest globular clusters. It is a fairly loose collection of stars as
compared to most others, and is an easy object even in binoculars, (and has
been seen with the naked eye on some occasions). There seems to be a linear
collection of stars bisecting the center. In small scopes this would give a
"flattened" appearance.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 5
|
|
15:18.4
|
+02° 05
|
26000
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
17.4'
|
5.8
|
Globular Cluster
|
Serpens
( SER )
|
244
|
|
Considered one of the
finest globular clusters in the sky, M5 is frequently compared to both M3 and
M13 in splendor. It's 13 billion year age makes M5
one of the oldest clusters known. Easily visible in binoculars it takes at
least a 4" telescope to be able to resolve some of its 1/2 million
stars.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 6
|
Butterfly Cluster
|
17:39.8
|
-32° 13
|
1500
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
15.0'
|
4.2
|
Open Cluster
|
Scorpius
( SCO )
|
377
|
|
M6, along with M7 nearby
are among the finest open clusters for small telescopes. M6 contains over
130 stars ranging between 6th and 11th magnitude. The central core of the
cluster has been likened to a "butterfly" in shape and is about
20 light years across.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 7
|
Ptolemy's Cluster
|
17:53.6
|
-34° 49
|
800
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
80.0'
|
3.3
|
Open Cluster
|
Scorpius
( SCO )
|
377
|
|
An easy object even for the
naked eye, M7 contains about 80 stars brighter than 10th magnitude. The
cluster is currently placed at about 800 light years distant and is about
270 million years in age.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 8
|
Lagoon Nebula
|
18:03.5
|
-24° 23
|
5100
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
80'X40'
|
5.2
|
Diffuse Nebula
|
Sagittarius
( SGR )
|
339
|
|
Better known as the
"Lagoon Nebula", M8 is one of the best diffuse nebula
easily visible to the naked eye. M8 surrounds the small young star cluster
NGC6530. The nebula is known for having a number small dark
"globules" of material believed to be stars at the very beginning
of formation or "protostars". Overall M8 is over 100 light years
across, its central regions a more modest 50 light years in diameter.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 9
|
|
17:18.9
|
-18° 31
|
26000
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
9.3'
|
7.3
|
Globular Cluster
|
Ophiuchus
( OPH )
|
337
|
|
M9 is a small but rather
bright globular cluster discovered by Messier in 1764. At 25,000 light
years, M9 is one of the nearer clusters and is receding away from us at 134
miles/second.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 10
|
|
16:56.9
|
-04° 06
|
20000
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
15.1
|
6.6
|
Globular Cluster
|
Ophiuchus
( OPH )
|
247
|
|
M10 is a very
"compressed" cluster "easily resolvable by moderate
means". M10 is receding away from us at a rate of 43 miles/second.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 11
|
Wild Duck Cluster
|
18:50.9
|
-06° 16
|
5500
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
14.0
|
5.8
|
Open Cluster
|
Scutum
( SCT )
|
295
|
|
M11 is described as an
"exceptional" open cluster bordering the northern edge of the
star clouds in Scutum. Resembling a globular cluster in binoculars M11
turns into a triangular swarm of stars containing hundreds of members
brighter than 14th magnitude. The cluster is about 15 light years in
diameter and considered to be about 500 million years old.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 12
|
|
16:47.0
|
-01° 57
|
24000
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
14.5
|
6.6
|
Globular Cluster
|
Ophiuchus
( OPH )
|
246
|
|
M12 is the slightly
dimmer and slightly larger sister cluster to M10. The two objects are about
2000 light years apart from each other. M12 was discovered by Messier in
1764.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 13
|
Hercules Cluster
|
16:41.5
|
+36° 28
|
23000
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
16.6
|
5.9
|
Globular Cluster
|
Hercules
( HER )
|
114
|
|
M13 is called the
"Great Globular Star Cluster in Hercules", the most splendid such
object in the Northern sky. Edmond Halley (of "Halley's Comet") discovered
M13 in 1714. The cluster is visible by the naked eye as a "fuzzy
star", but requires a 4 inch scope to resolve individual stars. With
more than 30,000 stars having been photographed, M13 has a total luminosity
of more than 300,000 suns and is about 160 light years across.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 14
|
|
17:37.4
|
-03° 15
|
33000
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
11.7
|
7.6
|
Globular Cluster
|
Ophiuchus
( OPH )
|
248
|
|
M14 is a rather
ill-defined globular cluster with no clear central core visible in small
telescopes. M14 is one of the only two globulars which are known to have
had nova (the other being M80). The cluster is approaching us at 77
miles/second.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 15
|
|
21:29.8
|
+12° 09
|
34000
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
12.3'
|
6.4
|
Globular Cluster
|
Pegasus
( PEG )
|
210
|
|
Compact M15 is known for
its brilliant and slightly oblate central core. Compared to others, M15 has
a rather large number of variable stars, numbering well over 100. Out on
the edge a small planetary nebula was discovered in 1927. M15 is also a
source of X-rays which may indicate that a supernova was once housed within
its borders.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 16
|
Eagle Nebula
|
18:18.5
|
-13° 47
|
5500
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
6.0'
|
6
|
Open Cluster
|
Serpens
( SER )
|
294
|
|
M16 "Eagle
Nebula" is normally considered an open cluster,
it is really a nebula in disguise. When viewed through small telescopes
about 100 stars or more are visible. However larger instruments will begin
to show some nebulosity. Photographically M16 reveals an
rich and highly complex diffuse nebula with multitudes of tiny eddies and
rifts swirling among the clouds.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 17
|
Omega Nebula
|
18:20.5
|
-16° 11
|
3000
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
11.0'
|
6
|
Diffuse Nebula
|
Sagittarius
( SGR )
|
294
|
|
M17, the "Swan
Nebula" also called the "Horseshoe Nebula, is one of the more pronounced
diffuse nebula. While there is no clear star cluster associated with M17,
over 35 nearby stars are related to the complex. The main body is about 12
light years long.
|
|
List Name
|
Common Name
|
R. A.
|
Dec.
|
Distance
|
|
M 18
|
|
18:19.7
|
-17° 08
|
4900
|
|
Size
|
Magnitude
|
Classification
|
Constellation
|
Uranometria
|
|
9.0
|
6.9
|
Open Cluster
|
Sagittarius
( SGR )
|
339
|
|
M18 is a relatively
minor open cluster containing about 12 stars in a loose formation.
|
|
List Name
|
|
