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The ancient story of the Dragon concerns the Golden Apples of the Hesperides
and Heracles' Eleventh Labour.
The eleventh task of Heracles (some references say it was the Twelfth)
was to steal the golden apples from the apple tree which Gaia (Mother Earth)
had given to Hera, Queen of the Heavens, at her wedding to Zeus.
Hera had chosen Ladon, a monstrous dragon with a hundred heads, to guard
her precious tree. So Ladon would lay in the garden, coiling himself
around the tree, and Hera feared no one would steal her apples.
Heracles went about collecting useful bits of information about the
dragon, finding out how to fool it and steal the apples. One suggestion
was to take along Atlas, who could be of some assistance.
For having opposed Zeus, Atlas had been punished by having to carry the
world on his shoulders. Heracles devised the perfect plan; he offered to
relieve Atlas of the terrible burden for an hour or so, long enough for
Atlas to perform a favour in return: fetch the golden apples from the
Garden of the Hesperides.
Atlas was in agreement; anything for a little rest. But there was one
problem: the terrible dragon. Heracles saw no problem. He shot an arrow
over the garden wall, killing Ladon instantly.
While Heracles hoisted up the globe, Atlas trotted off to retrieve the three golden apples. At his return Atlas found he could go on living quite happily without the weight of the world on his shoulders, so he told Heracles, "just a few more months and I'll return", planning to leave Heracles the task of carrying the worldly globe.
Heracles agreed but asked Atlas if he could get more comfortable. He begged Atlas to take the globe for a moment while he put some padding on his head. Atlas placed the apples on the ground and picked up the globe.
Heracles thanked him very much and walked away with the three apples.
As for Ladon, Hera felt miserable over its loss and placed it in the
heavens, coiled around the north pole.
As it wraps itself around the northern hemisphere Draco is circumpolar, not far from the North Pole. In fact Thuban (alpha Draconis) was once the Pole Star, at about the time these stories were being told for the first time.
There are a full range of Bayer stars in the
constellation. While there are few deep sky objects of any interest (and just one Messier) the constellation does have a wide variety of interesting binaries to investigate, some of which are listed further below.
The main object of the archaeologists' study is the Great Pyramid of
Khufu. It is claimed that a particular passage in the pyramid was built
to point at Thuban as that star dipped to its lower culmination.
However, if the above assumption is true, then the pyramid would have been built at around 2200 BC. The problem is that Khufu is about five hundred years older.
There are many books and articles on the subject (and no doubt several
web pages on the Internet) for those who wish to delve deeper into the
problem or to study the alignment of other stars with ancient artifacts.
Nu Draconis is a splendid fixed binary, found in the dragon's head. Two
similar 4.9 visual magnitude stars: PA 312º and separation 61.6".
Psi Draconis is also easily resolved: 4.9, 6.1; PA 15º, separation
30.3"
Omicron Draconis has a fine colour contrast, orange and blue.
Magnitudes 4.7, 7.5; PA 326º, separation 34.2".
17 Draconis forms a magnificent fixed triple with 16 Draconis. 17AB:
5.5, 6.4, PA 108º, separation 3.4"; 16 Draconis is component C: PA 194,
separation 90.3".
26 Draconis is a close binary with orbit of
76 years. The component is currently at PA 334º and separation 1.6". There is a faint (10m) very wide third member, at PA 162º and separation 12.3'.
41 and 40 Draconis (Struve 2308) form a pleasant, fairly wide,
binary of two cream-coloured stars: 5.7, 6.0: PA 232º, 19.3". Note that 41 is the primary.
Struve 2398 is an extremely near binary at only 11.3 light years.
It consists of two red dwarfs, 8.0, 8.5; PA 163º, separation 15.3". It is thought the companion has an orbit of roughly 350 years.
The binary is found just between omicron Draconis (which to the east) and 39 Draconis.
M102 (NGC 5866) is an edge-on galaxy with dust lane and brightly
glowing centre.
NGC 5907 is in the same region one degree east of M102. This is another edge-on (nearly flat) galaxy with dust lane.
NGC 5985 is an inclined spiral, quite faint unless under ideal
conditions.
NGC 6543: a planetary nebula that appears as a miniscule blue-green disk. Because of its blue-green colouring, it is sometimes called the Cat's Eye Nebula. It's located halfway between delta and zeta Draconis. It's exact distance isn't known; estimates vary from 1500 to 3500 light years.
For a closer appreciation of Draco, visit the Binocular Section.
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© Richard Dibon-Smith.
