Orion is very popular constellation. Specially, for folks who are doing their 1st stargazing session. It is brightest constellation. Orion contain three brightest stars; therefore, it is clearly visible in night sky. It having three stars in line at center of constellation, which known as ‘Orion Belt’. Due to this unique Pattern, it is easily spotted.
The pattern we get after joining the dot, is looks like men holding shield and sword. Because of this, Orion is also known as ‘The Hunter’, according to mythology. Its genitive is Orionis and abbreviation are Ori. Orion is on 26th in size ranking. It covers 594 sq. deg area in sky. Its right ascension is 5 hours, and its declination is 5 degree. The hunter covers 1.440% of the sky. Rigel is the brightest star in constellation.
Myths
There is various mythology. According to Greek myth, Orion is son of Poseidon-the god of sea. It was hunting with goddess of wild animals Artemis and boasted he could kill any creature on earth. This angered the earth goddess Gaia. She sent giant Scorpio to kill Orion. The Scorpio succeeded and Zeus placed the hunter amongst the stars. He also immortalized the Scorpio and placed it opposite to the Orion in the sky, where it would never harm him again. Zeus is parent of Artemis. In other stories, Orion was chasing seven sisters in search of wife. In Babylon, Orion was the shepherd. In ancient Egypt, he was Osiris-the sun god. Few native Americans tribes know him as the winter maker, because during this constellation winter arises.
How to detect
Spotting the Orion is not that hard. It’s a winter constellation. It can be seen between November to March. We can spot Orion by its Orion belt. Three stars in line formation enclosed in other four stars of constellation. The other way is by spotting Sirius star. Sirius is one of the bright stars in night sky. It is lie in constellation of Canis Major. By finding Sirius star, one can easily detect Orion constellation.
Orion as a signpost
For a new stargazer, Orion is helpful for finding others constellation. In front of Orion shield, there is constellation of Taurus. If we come down little bit then we can find constellation of Eridanus. Above the head of Orion star Meissa , there exist constellation of Auriga. On opposite side of his sword, one can find constellation of Gemini. Canis minor lies below the Gemini. If we look in front of Alnitak , we can spot Monoceros constellation. Below it and in front of Saiph, there is Canis major. Lastly, below the Orion constellation of Lepus can be found.
Major Stars
Orion contain seven main stars and 81 Bayer stars.
Betelgeuse
Betelgeuse is known as Alpha Orionis. It is M type supergiant. It is 2nd brightest star in Orion. Betelgeuse is variable star. It is near to its death. The death is expected in result of supernova. This is most likely to occur within the next 100,000 years. It is 624 light years away having appearing magnitude of 0.42.
Rigel
It is known as Beta Orionis. It is B type blue supergiant. It is 6th brightest star in the night sky. Rigel will soon pass his supergiant stage and either collapsing in supernova or became a white dwarf. Its apparent magnitude is 0.18. Rigel is 772 light year away.
Bellatrix
It is also known as Gamma Orionis. Bellatrix is also known as “female Warrior” and Amazon star. It is 27th brightest star in night sky. Bellatrix is B type blue giant. But it is too small to explode in supernova. Bellatrix is 245 light years away having apparent magnitude 1.64.
Mintaka
It is faintest star in Orion belt. It is also known as Delta Orionis. It is multiple star system, made of B type blue giant and O type main sequence star. Mintaka is 916 light years away having App. magnitude of 2.20. It is 90,000 times more luminous than sun.
Alnilam
It is B type blue supergiant. Alnilam also known as Epsilon Orionis. It is the brightest star in Orion belt situated in middle. It is the farthest star in Orion at 1344 light years away. Apparent magnitude of Alnilam is 1.69. Its ultraviolet light is 375,000 times more luminous than sun.
Alnitak
Alnitak means “the girdle”. It is known as zeta Orionis. Alnitak is the triple star system. It is 800 light years away from us and 100,000 times more luminous than sun. Its apparent magnitude is 1.88.
Saiph
It is also known as Kappa Orionis. This star is 650 light years away from us, which is nearly equal to Rigel but still looks fainter. Saiph having Magnitude of 2.07.
Meissa
It is known as lambda Orionis. Meissa means “shining star”. Meissa forms a Orion head. It is multiple star system. Its combine apparent magnitude is 3.33. It is 1042 light years away.
Deep sky Objects
• M42
The Orion Nebula. The one of the most prominent nebulae in night sky. The nebula is cloud of hydrogen gas, stellar nursery where new stars are forming. Trapezium cluster has many newborn stars and brown dwarfs. It is 1500 light years away. The new born stars light up the nebula from inside. Using binoculars, clouds of stars, luminous gas and dust can be observed. If we can look through telescope in the middle of the nebula, then we will see trapezium asterism.
• IC434
The Horsehead Nebula. It contains a dark dust cloud. This object looks like horse head. The Horsehead Nebula situated in Orion belt below the Alnitak stars.
• M78
It is also known as NGC 2068. It is 1600 light years away. It is reflection nebula in Orion.
• NGC 2024
The Flame Nebula. It is emission nebula in the Orion. This nebula located 1350 light years away.