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Draco (constellation)

Draco (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 one of the 48 constellations listed by Ptolemy.

Contents

Notable features

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, Etamin (γ Draconis), whose magnitude is 2.23.

There are several double stars of interest in Draco. Kuma (ν Draconis) consists of two components of magnitude 4.9, 62 arcseconds apart. They can be split with binoculars.

R Draconis and T Draconis are Mira-type variable stars. 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.

Notable deep sky objects

One of the deep-sky objects 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.

Mythology

There are many myths behind Draco, due to its resemblence to a dragon [1]. In the first legend, Draco represents the dragon killed by Cadmus before founding the city of Boeotia. In the second legend, it represents the dragon that guarded the Golden Fleece and was killed by Jason.

In another myth, it represents Ladon, the dragon that guarded the apples of the Hesperides, one of The Twelve Labours of Herakles. Due to its position and nearby constellations in the zodiac sign of Libra (i.e. Ursa Major, Ursa Minor, and Boötes), formed the origin of the myth.

Table of leading stars

The following table lists all stars in Draco that have either a Bayer or Flamsteed designation, or are magnitude 4.5 or brighter.

Common name Bayer designation Flamsteed designation Variable designation Other designation Right ascension (J2000) Declination (J2000) Magnitude
HR 3751 09h 37m 05.2s +81° 19' 35" 4.29
Gianfar λ 1 11h 31m 24.2s +69° 19' 52" 3.84
2 11h 36m 02.8s +69° 19' 22" 5.20
3 11h 42m 28.4s +66° 44' 42" 5.30
4 CQ 12h 30m 06.7s +69° 12' 04" 4.95v
κ 5 12h 33m 29.0s +69° 47' 18" 3.87v
6 12h 34m 44.0s +70° 01' 19" 4.94
7 12h 47m 34.4s +66° 47' 25" 5.43
8 12h 55m 28.5s +65° 26' 19" 5.24
9 12h 59m 55.1s +66° 35' 50" 5.32
i 10 CU ADS 9039 13h 51m 25.9s +64° 43' 24" 4.65v
Thuban α 11 14h 04m 23.3s +64° 22' 33" 3.65
Ed Asich ι 12 15h 24m 55.8s +58° 57' 58" 3.29
θ 13 16h 01m 53.3s +58° 33' 55" 4.01
η 14 ADS 10058 16h 23m 59.5s +61° 30' 51" 2.74
15 16h 27m 59.0s +68° 46' 05" 5.00
16 ADS 10129C 16h 36m 11.5s +52° 54' 01" 5.53
17 ADS 10129AB 16h 36m 13.9s +52° 55' 28" 5.08
g 18 16h 40m 55.1s +64° 35' 21" 4.83
h 19 16h 56m 01.7s +65° 08' 05" 4.89
20 ADS 10279 16h 56m 25.2s +65° 02' 21" 6.41
Arrakis μ 21 ADS 10345 17h 05m 19.8s +54° 28' 13" 4.92
Aldhibah ζ 22 17h 08m 47.2s +65° 42' 53" 3.17
Rastaban β 23 ADS 10611 17h 30m 26.0s +52° 18' 05" 2.79
Kuma ν¹ 24 ADS 10628A 17h 32m 10.6s +55° 11' 03" 4.88
Kuma ν² 25 ADS 10628B 17h 32m 16.0s +55° 10' 23" 4.87
f 27 17h 31m 57.9s +68° 08' 06" 5.05
26 ADS 10660 17h 34m 59.5s +61° 52' 30" 5.23
ω 28 17h 36m 57.1s +68° 45' 29" 4.80
Dsiban ψ¹ 31 ADS 10759 17h 41m 57.2s +72° 09' 11" 4.27
30 17h 49m 04.3s +50° 46' 52" 5.02
Grumium ξ 32 17h 53m 31.7s +56° 52' 22" 3.75
35 17h 49m 27.0s +76° 57' 46" 5.04
Etamin γ 33 ADS 10923 17h 56m 36.4s +51° 29' 20" 2.23
ψ² 34 17h 55m 11.2s +72° 00' 18" 5.45
40 ADS 11061B 18h 00m 03.4s +80° 00' 03" 6.04
41 ADS 11061A 18h 00m 09.2s +80° 00' 15" 5.68
36 18h 13m 53.8s +64° 23' 50" 5.03
37 18h 15m 17.0s +68° 45' 21" 5.95
φ 43 ADS 11311 18h 20m 45.5s +71° 20' 16" 4.22v
b 39 ADS 11336 18h 23m 54.5s +58° 48' 02" 4.98
χ 44 18h 21m 03.4s +72° 43' 58" 3.57
42 18h 25m 59.1s +65° 33' 49" 4.82
d 45 18h 32m 34.5s +57° 02' 44" 4.77
c 46 18h 42m 37.9s +55° 32' 22" 5.04
50 18h 46m 22.2s +75° 26' 02" 5.35
ο 47 ADS 11779 18h 51m 12.1s +59° 23' 18" 4.66v
48 18h 56m 45.0s +57° 48' 54" 5.66
υ 52 18h 54m 23.9s +71° 17' 50" 4.82
49 19h 00m 43.4s +55° 39' 30" 5.48
51 19h 04m 55.2s +53° 23' 48" 5.38
55 19h 09m 45.8s +65° 58' 43" 6.25
53 19h 11m 40.5s +56° 51' 33" 5.12
54 19h 13m 55.2s +57° 42' 18" 4.99
Nodus Secundus δ 57 19h 12m 33.3s +67° 39' 42" 3.07
59 19h 09m 09.8s +76° 33' 38" 5.13
τ 60 19h 15m 33.0s +73° 21' 20" 4.45
π 58 19h 20m 40.1s +65° 42' 53" 4.59
Alsafi σ 61 19h 32m 21.6s +69° 39' 40" 4.68
Tyl ε 63 ADS 13007 19h 48m 10.4s +70° 16' 04" 3.83
e 64 20h 01m 28.5s +64° 49' 16" 5.27
65 20h 02m 20.3s +64° 38' 04" 6.57
ρ 67 20h 02m 49.1s +67° 52' 25" 4.51
69 19h 59m 36.6s +76° 28' 53" 6.20
66 20h 05m 32.8s +61° 59' 44" 5.39
68 20h 11m 34.9s +62° 04' 43" 5.75
71 DE 20h 19m 36.7s +62° 15' 27" 5.72v
73 AF 20h 31m 30.4s +74° 57' 17" 5.20v
75 20h 28m 14.6s +81° 25' 22" 5.46
74 20h 29m 27.5s +81° 05' 29" 5.96
76 20h 42m 35.2s +82° 31' 52" 5.75

Source: The Bright Star Catalogue, 5th Revised Edition

Table of notable double stars

Designation Right Ascension Declination Magnitudes
μ (Arrakis) 17h 05m 19.8s +54° 28' 13" 5.80, 5.83
ν¹+ν² (Kuma) 17h 32m 13.3s +55° 10' 43" 4.88, 4.87
ε (Tyl) 19h 48m 10.4s +70° 16' 04" 3.83, 7.4

Table of notable variable stars

Designation Right Ascension Declination Range Period
R 16h 32m 40.3s +66° 45' 18" 6.7-13.2 245.5 days
T 17h 55m 37.4s +58° 13' 24" 7.2-13.5 421.2 days
RY 12h 54m 28.1s +66° 15' 52" 6.5-8.0 172 days

Table of notable deep sky objects

Designation Type Right Ascension Declination Size Magnitude
NGC 6504 Galaxy 17h 49m 24.0s +70° 09' 00" 6.2'×2.3' 10.2
NGC 6543 Planetary nebula 17h 58m 33.4s +66° 37' 59.1" 23"×17" 8.1
NGC 5866 (M102?) Galaxy 15h 06m 29.3s +55° 45' 47" 6.5'×3.0' 11.1

Last updated: 05-07-2005 14:16:00
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