Celestial Events SA
Orion - Constellation of the Month
Updated: Apr 5, 2020
Despite not being a sign of the Zodiac, Orion is probably the most recognised constellation in the sky. It was known to the Sumerians and later adopted by the Greeks but its most interesting past lies with the Egyptians.
Some astronomers believe that the Great Pyramids of Giza represent the famous stars of Orion’s Belt, right down to their orientation and size. The 2 larger pyramids represent the brighter Alnilam and Alnitak, whilst the smaller of the pyramids represents the dimmer, and slightly offset, Mintaka.
The Egyptians saw Orion as Osiris, the god of the afterlife and there are shafts in the royal chambers within that seem to line up perfectly with Orion; and to Sirius in Canis Major. Sirius was seen as Isis, Osiris’s sister and lover. Egypt’s latitude meant that Orion would disappear from the night sky for a period of 70 days each year and during this time, no burials were conducted because the path to the afterlife, and Osiris, was closed. 72 days is also the official mourning period for Egyptian pharaohs. It should be noted however that this is merely conjecture and no definitive proof exists to substantiate these findings.
The constellation of Orion represents the great hunter wielding his sword/club and shield and being accompanied by his faithful hunting dogs, Canis Major and Canis Minor. Its mythology has direct links to the constellation of Scorpius.
Orion was a renowned hunter and boasted often that no beast on Earth was a match for him. In one version of the mythology, Gaia, the goddess of the Earth, sent a giant scorpion to teach Orion some humility in the face of nature. A great battle raged and both were killed during the fight. Other stories have a more heroic angle, suggesting that Orion died protecting his lover’s mother from the beast.
To honour them, Zeus placed both combatants in the sky at exact opposites of the celestial sphere. As Orion sets, Scorpius rises, giving the impression that the scorpion is chasing the fleeing Orion across the sky for eternity.
Orion contains many famous stars but the most notable is Betelgeuse, a red supergiant who name stems from the Arabic for ‘armpit of the giant’.
Betelgeuse is a behemoth of a star, estimated to be around 1.5 billion kms in diameter. If Betelgeuse were to replace our Sun, everything up to and including Jupiter would be enveloped by the star.
Betelgeuse is coming to the end of its life and is expected to go supernova in the near future (astronomically speaking). When this happens, the resulting explosion will be visible in the daytime sky and be brighter than the full Moon at night!
DEEP SKY OBJECTS
The Great/Orion Nebula (M42) is the closest, and brightest area of star formation visible in our night skies.
It can be found by looking at the central ‘star’ of Orion’s sheathed sword. A simple pair of binoculars will show a hazy patch, while small amateur telescopes can begin to resolve detail and long exposure photography will expose the stunning colours.
Within the nebula, hundreds of baby stars are being born, coalescing from enormous clouds of dust and gas and it is their light that illuminates the surrounding features.