Draco (constellation)

Draco

Constellation
List of stars in Draco
Abbreviation	Dra
Genitive	Draconis
Pronunciation	/ˈdreɪkoʊ/, genitive /drəˈkoʊnɨs/
Right ascension	17
Declination	+65
Area	1083 sq. deg. (8th)
Main stars	14
Bayer/Flamsteed stars	76
Stars with planets	5
Stars brighter than 3.00m	3
Stars within 10.00 pc (32.62 ly)	6
Brightest star	Gamma Draconis (2.24m)
Messier objects	1
Meteor showers	Draconids
Bordering constellations	Boötes Hercules Lyra Cygnus Cepheus Ursa Minor Camelopardalis Ursa Major
Visible at latitudes between +90° and −15°. Best visible at 21:00 (9 p.m.) during the month of July.

Draco is a constellation in the far northern sky. Its name is Latin for dragon. Draco is circumpolar (that is, never setting) for many observers in the northern hemisphere. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations today.

Notable features

Eltanin (Gamma Draconis) is the brightest star in Draco, with an apparent visual magnitude of 2.24 magnitude units.

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. Another is the Draco Dwarf Galaxy, one of the least luminous galaxies with an absolute magnitude of -8.6 and a diameter of only about 3,500 light years, discovered by Albert G. Wilson of Lowell Observatory in 1954.

The star Thuban (α Draconis) was the northern pole star around 2700 BC, during the time of the ancient Egyptians. Due to the effects of precession, it will once again be the pole star around the year 21000 AD.

Mythology

File:Dracourania.jpg

Draco coils around the north celestial pole, as depicted in Urania's Mirror, a set of constellation cards published in London c.1825

Draco is among the earliest of the constellations to have been defined; in one of the oldest known astronomical records, the ancient Egyptians identified it as Tawaret, the goddess of the northern sky in their pantheon of deities. Considered ever-vigilant because the constellation never set, she was depicted a fierce protective goddess whose body was a composite of crocodile, human, lioness, and hippopotamus parts.

The Greeks named it Draco the dragon. In one of the more famous European myths, Draco represents Ladon, the dragon sometimes depicted with one hundred heads who guarded the golden apples of the Hesperides. The eleventh of the Twelve Labours of Heracles was to steal the golden apples. He put Ladon to sleep with music, which enabled Heracles 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 Greek legend, Draco represents the dragon killed by Cadmus before founding the city of Thebes, Greece. In a third legend, it represents the dragon that guarded the Golden Fleece (occasionally revealed as the sleeping or nearly dead figure of Ladon) and was killed by Jason. The fact that the stars of this circumpolar constellation never set plays an important part in its mythologies.

In Roman legend, Draco was a dragon killed by the goddess Minerva and tossed into the sky upon his defeat.

Early Christians originally of the Roman or Greek faith then depicted Draco as the serpent who tempted Adam and Eve in the Garden of Eden.

The Arabs did not interpret the constellation as a dragon, seeing instead an asterism called the Mother Camels.

References

• Ian Ridpath and Wil Tirion (2007). Stars and Planets Guide, Collins, London. ISBN 978-0007251209. Princeton University Press, Princeton. ISBN 978-0691135564.

who cares its ugly

External links

• The Deep Photographic Guide to the Constellations: Draco
• Star Tales – Draco