Download PROPOSED OCTOBER VIEWING LIST

OCTOBER 2008 VIEWING LIST
Object
Type
Size
Distance
Coordinates
14” Scopes
NGC 891**
Gal
M16**
EN
NGC 6946**
Gal
NGC 7023
OCRN
NGC 7009*
PN
M15
GC
M2
GC
NGC 7293*
PN
Stephan’s Quintet**
NGC7331**
Gal
NGC 7635
EN
M52
OC
NGC 7662
PN
12’
7’
11’
18’
44”
18’
16’
16’
11’
16’
65’
32”
31,000,000 LY
7,000 LY
10,000,000 LY
1,400 LY
2,400 LY
33,600 LY
37,500 LY
450 LY
280,000,000 LY
46,000,000 LY
7,100 LY
5,000 LY
3,200 LY
02h 23’
18h 19’
20h 35’
21h 01’
21h 04’
21h 30’
21h 34’
22h 30’
22h 36’
22h 37’
23h 21’
23h 24’
23h 26’
+42 21’
-13 47’
+60 09’
+68 10’
-11 22’
+12 10’
-00 49’
-20 48’
+33 57’
+34 25’
+61 12’
+61 35’
+42 32’
4” Refractor
M11
OC
Gamma Delphini DS
S Cephei
CS
14’
-
6,000 LY
104 LY
1,353 LY
18h 51’
20h 47’
21h 35’
- 06 16’
+16 07’
+78 37’
Abbreviations:
MS = Multiple Star, EN = Emission Nebula, RN = Reflection Nebula, Gal = Galaxy, GC = Globular
Cluster, LY = Light Year, OC = Open cluster, PN = Planetary Nebula, SR = Supernova Remnant,
CS = Carbon Star, * = Video imaging optional, ** = Video imaging recommended
OBJECT DESCRIPTIONS
NGC 891 In the constellation Andromeda (an-DROM-eh-duh) is a spiral galaxy seen nearly edge-on.
Also known as Caldwell 23, it was discovered by Caroline Herschel in 1784, this galaxy is approximately
110,000 light years in diameter and contains over 150 billion stars. Note the faint, narrow dust lane.
M16 is an emission nebula in the constellation Serpens Cauda (SIR-penz CAW-da). Commonly known
as the Eagle Nebula, it is also known for the interesting internal formation popularly known as the “Pillars
of Creation, an area of intense star formation with most stars in the region being less than 5.5 million
years old. The full extent of the nebula is about 15 light years across. Look for the bright rims on the
pillars, which define the shock front of the compressing gas clouds that continue to form new stars.
NGC 6946 is a type Sc spiral galaxy in the constellation Cepheus (SEE-fee-us). Although only 10 million
light years away it glows at a feeble 8.9 magnitude due to the interference of gas and dust within our
own galaxy. Type Sc galaxies are identified by multiple spiral arms and a small amorphous nuclear
region. Note the similarity of shape with another Sc galaxy, M-51, observed earlier in the year.
NGC 7023 is a reflection nebula in the constellation Cepheus (SEE-fee-us). Commonly known as the Iris
Nebula, this object is physically associated with the 7th magnitude star, SAO 19158. Unlike gaseous
emission nebulae, reflection nebulae do not radiate light. Instead, motes of dust reflect the light of bright
stars in the vicinity.
NGC 7009 in the constellation Aquarius (ã-QUAIR-ee-us) is commonly known as the Saturn Nebula due
to the extensions on opposite sides of the oblong disk. Discovered by William Herschel in 1782, this 8th
magnitude nebula has an 11.5 magnitude white dwarf in the center. Use an OIII filter for best image.
M15 is a densely compacted globular cluster in the constellation Pegasus (PEG-uh-sus). This may be
the densest globular cluster in our galaxy. The accepted diameter of M15 is about 175 light years. This
globular cluster may contain a supermassive black hole.
M2 is a globular cluster in the constellation Aquarius (ã-QUAIR-ee-us). Discovered by Italian astronomer
Maraldi in 1746, M2 has a diameter of about 175 light years and contains about 150,000 stars, the
brightest of which are red and yellow giants.
NGC 7293 is a planetary nebula in the constellation Aquarius (ã-QUAIR-ee-us) ). Also listed as Caldwell
63, this large, dim object is commonly known as the Helix, and the Sunflower Nebula. If observing
visually, use of low magnification (31mm eyepiece) and an OIII filter is recommended.
Stephan’s Quintet is a tight grouping of small, faint galaxies including NGC 7317, 7318, 7318A, 7319,
and another slightly brighter foreground galaxy NGC 7320, in the constellation Pegasus (PEG-uh-sus).
The string of four galaxies is roughly 280 million light years distant, while NGC 7320 is located a mere
35 million light years away. This group will require some deft camera tuning but it is a worthwhile prize.
NGC7331 Discovered by William Herschel in 1784 in the constellation Pegasus (PEG-uh-sus), this is a
bright spiral galaxy viewed nearly edge-on. Despite this orientation, look for evidence of spiral structure.
NGC 7635 is an emission nebula in the constellation Cassiopeia (Kas-ee-oh-PEE-ah). It is also known
as the Bubble Nebula. At approximately 10 light years in diameter, it is a fine representative of the
classic planetary nebula. Visual observers will benefit from the OIII filter.
M52 is an open cluster in the constellation Cassiopeia (Kas-ee-oh-PEE-ah). It contains several hundred
stars that formed at roughly the same time. Note the red star that seems so out-of-place in the cluster. It
is actually a foreground star that is superimposed on the cluster. Use low magnification for best results.
NGC 7662 In the constellation Andromeda (an-DROM-eh-duh) is a planetary nebula. Commonly known
as the Blue Snowball Nebula, it has a distinctive bluish cast as seen by many observers. Observe it
visually with and without the OIII filter.
M11 Known as the Wild Duck cluster, this open cluster in the constellation Scutum, (SKEW-tum) is seen
best with the 4” refractor at low magnification. It contains more than 2900 stars and is estimated to be
about 250 million years old.
Gamma Delphini is a binary with a deep yellow primary and a pale greenish secondary. This true binary
is about 104 light years away with a period of revolution of 3200 years. Their highly eccentric orbits carry
them from 40 to 600 Astronomical Units apart. Question: How far is an Astronomical Unit?
S Cephei is a Carbon Star, a red giant with a large amount of carbon dust floating in it’s upper
atmosphere. The dust passes red light, making carbon stars the reddest stars to be seen through a
telescope. At magnitude 7.5, it is a beautiful deep red and, at its high declination may be glimpsed all
year long. Observe it with both the 4” refractor and the 14” at low magnification for best color
F. Lockhart