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Dra
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Draconis
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the Dragon
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15
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+75
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1083
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8th
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3
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&gamma Dra (Etamin)
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223
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"http://wwwinformationdelightinfo/encyclopedia/entry/Vrhbosna/Draconids" class="copylinks">Draconids
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"http://wwwinformationdelightinfo/encyclopedia/entry/Vrhbosna/Ursa_Major" class="copylinks">Ursa Major
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90
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15
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July
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(
Latin for ''
Dragon '') is a far northern
Constellation that is
Circumpolar for many
Northern Hemisphere observers. It is one of the 88 modern constellations, and is also one of the 48 constellations listed by
Ptolemy .
The star
Thuban (α Draconis) was the northern
Pole Star around
2700 B.C. , during the time of the
Ancient Egyptians . Due to the effects of
Precession , it will once again be the pole star around the year 21,000 A.D.
Although
Thuban 's
Bayer Designation is α Draconis, it is not the brightest star in the constellation. At
Magnitude 3.65, it is more than a magnitude fainter than the brightest star,
γ Draconis (Eltanin), whose magnitude is 2.23.
There are several
Double Star s of interest in Draco.
ν Draconis (Kuma) consists of two components of magnitude 4.9, 62
Arcsecond s apart. They can be split with binoculars.
R Draconis and
T Draconis are
Mira -type
Variable Star s. R ranges between magnitudes 6.7 and 13 with a period of 245.5 days, and T ranges between magnitudes 7.2 and 13.5 with a period of 421.2 days.
σ Draconis is relatively close to
Earth , only 18.8
Light Year s away.
The north pole of the
Ecliptic lies within the constellation Draco. This point is very close to the galaxy
NGC 6552 and within 10
Arcminute s of the
Cat's Eye Nebula - NGC 6543
One of the
Deep-sky Object s in Draco is the
Cat's Eye Nebula (NGC 6543), a
Planetary Nebula that is said to look like a blue disc. There are several faint
Galaxies in Draco, one of which is the
Lenticular Galaxy NGC 5866 , sometimes considered to be
Messier Object 102 .
There are a number of myths behind the constellation Draco, due to its resemblance to a dragon
{Link without Title} .
In the most famous of the myths, Draco represents
Ladon , the hundred-headed dragon that guarded the golden apples of the
Hesperides . The eleventh of
The Twelve Labours of
Heracles was to steal the golden apples. Herakles killed Ladon with a poisoned arrow, allowing him to freely take the golden apples. According to the legend,
Hera later placed the dragon in the sky as the constellation Draco. Due to its position and nearby constellations in the
Zodiac sign of
Libra (i.e.
Ursa Major ,
Ursa Minor , and
Boötes ), the group of constellations can be seen to tell the tale of the eleventh labour.
In another legend, Draco represents the
Dragon killed by
Cadmus before founding the city of
Boeotia . In a third legend, it represents the dragon that guarded the
Golden Fleece and was killed by
Jason .
In a somewhat Roman/Greek legend, the dragon pictured in the constellation of Draco was said to guard the polar star. By astronomical chance, the Dragon's Head and Dragon's Tail marks the positions of the lunar nodes, those points where the paths of the solar and lunar orbits intersect and where solar and lunar eclipses may occur. The Dragon's head refers to the ascending node, the Dragon's tail the descending node. In several cultures, an eclipse was attributed to the disappearance of the moon or sun as they were swallowed by a dragon. The fact that the stars of this circumpolar constellation never set plays an important part in its mythologies.
Very anciently, the stars of Ursa Minor were considered to represent the Dragon's wing.
The following table lists all stars in Draco that have either a
Bayer or
Flamsteed Designation , or are
Magnitude 4.5 or brighter.
Source:
The Bright Star Catalogue, 5th Revised Edition
:Stars with proper names:
- (11/α Dra) 3.67 or '''''Adib''''' or '''''Dragon’s Tail'''''
- : < الثعبان ''aθ-θucbān'' The basilisk
- : < الذئبة ''að-ði'bah'' The female wolf
- ( 33/γ Dra ) 2.24 ''Etanin, Ettanin'' or '''''Zenith Star''''' (or ''Rastaban'' [''Rastaben''], see β Dra )
- : < راس التنين ''ar-rās at-tinnīn'' The head of the dragon (also called ''Caput Draconis'')
- ( 57/δ Dra ) 3.07 or '''Nodus Secundus''' II or '''''Aldib'''''
- : < التيس ''at-tais'' The billy goat
- : < ''nōdus secundus'' The second knot
- : < الذيب\الذئب að-ðīb: The wolf
:Stars with Bayer designations:
::
13/θ Dra 4.01;
5/κ Dra 3.85;
47/ο Dra 4.63;
58/π Dra 4.60;
67/ρ Dra 4.51;
60/τ Dra 4.45;
52/υ Dra 4.82;
44/χ Dra 3.55;
43/Φ Dra 4.22;
28/ω Dra 4.77;
39/b Dra 4.98;
46/c Dra 5.03;
45/d Dra 4.77;
64/e Dra 5.22;
27/f Dra 5.07;
18/g Dra 4.84;
19/h Dra 4.88;
10/i Dra 4.58;
15/A Dra 4.94
:Stars with Flamsteed designations:
::
2 Dra 5.19;
3 Dra 5.32;
4 Dra 5.01;
6 Dra 4.95;
7 Dra 5.43;
8 Dra 5.23;
9 Dra 5.37;
16 Dra 5.53;
17 Dra – 5.07, 6.53;
20 Dra 6.40;
26 Dra 5.23;
29 Dra 6.61;
30 Dra 5.02;
34 Dra 5.43;
35 Dra 5.02;
36 Dra 4.99;
37 Dra 5.96;
38 Dra 6.79;
40 Dra 6.11;
41 Dra 5.74;
42 Dra 4.82;
48 Dra 5.67;
49 Dra 5.51;
50 Dra 5.37;
51 Dra 5.40;
53 Dra 5.13;
54 Dra 5.00;
55 Dra 6.26;
59 Dra 5.11;
65 Dra 6.27;
66 Dra 5.40;
68 Dra 5.70;
69 Dra 6.20;
71 Dra 5.71;
73 Dra 5.18;
74 Dra 5.96;
75 Dra 5.38;
76 Dra 5.75;
77 Dra 5.91;
78 Dra 5.18;
205 Dra 7.29
:Other notable stars:
