Orion (Pronounciation:Ore-i-on, Abbrev:Ori, Latin:Orionis) is a constellation, one of 88 constellations that the night sky is divided into. The sky is not divided up equally between the constellations. Orion takes up 594.12 sq. degrees of the night sky which equates to 1.44% of the night sky. Orion is the 26th largest in terms of size in the night sky.
The constellation name means The Hunter . The constellation is one of the original constellations that was devised by the Ancient Greco-Egyptian astronomer Ptolemy who lived between 90 A.D. and 168 A.D.
There are 20 stars that make up the main constellation. The hipparcos satellite scanned and detailed 1952 stars. There are 128 stars that can be seen with the naked eye in the constellation on a very clear night sky.
Orion is not a member of the Zodiac group of twelve constellations that appear when the Sun sets. Orion is an equatorial constellation that can be seen by countries nearest the Equator.
The distance to Orion is not calculable because all the stars that make up the constellation are at various distances. The best answer for distance to Orion is to calculate the average distance of the stars.
There are 19 Extrasolar Planets (Exoplanets) in this constellation that are detailed on this site. There is a dedicated page for exoplanets in Orion. The current largest star so far identified in the constellation of Orion is Betelgeuse. For a list of named stars, that is stars that don't start HD or HIP, please visit Orion Star List Page.
There are 3 deep space objects that were identified by Charles Messier in this constellation. There are 1 non-Messier deep space objects that are covered on this site and the list is below.
The image at the top right of this page was generated using Night Vision, a free to use and download application by Brian Simspon.
The caveat of these stars are that they are catalogued on this site. If you know of a star that is nearer or further then do let me know in the comments and I'll add it to the site. The stars mentioned are from the Hipparcos catalogue or have been added because of their special status.
The nearest star to Earth is Gliese 205 which is roughly about 18.45 Light Years from the Earth. The nearest star to the Earth with an exoplanet is HIP 22627 which is about 40.08 Light Years.
The furthest star that is located in the constellation is HIP 27033 and it is 326163.3 light years away from the Sun. The furthest figure is derived from either the 1997 or 2007 Hipparcos star catalogue parallax figure and it has been known to produce distances that are wrong.
The dimmest star that can be seen in Orion with the naked eye is HD 44497. The dim star has an apparent magnitude of 6. The dimmest star that a person is able to see with their naked eye is 6.0 magnitude based on the table in the reference. Ref: University of Michigan
Betelgeuse is the star that is most likely to turn into supernova soon. However given that we are so far away from the star, it will not affect life on Earth. It will also not happen for thousands of years but when it does, it will be relatively near compared to other explosions. It is one of the largest stars out there in the Milky Way.
The belt makes Orion one of the most easy constellations to spot in the night sky due to the alignment of the three stars, Alnitak, Alnilam and Mintaka. Once you have located the belt, working out the other stars should be easy.
The cryptically named star is one of the first stars to have an exoplanet imaged. CVSO 30 is located slight more north of the Belt of Orion but you won't be able to see with the naked eye as it is too far away.
Rigel similar to the mans name of Nigel is a blue white star and one of the brightest in the night sky. Located to the east of the constellation is the Witch-Head Nebula, a nebula that resembles a head is lit up by the glow from the star. Although close to Rigel, the Witch-Head Nebula is located within the neighbouring Eridanus constellation.
Orion was a strong hunter who attracted the eyes of many women and goddesses. This caused a lot of jealousy. He was created for a poor shepherd when he looked after Zeus one night. The goddess Artemis was infatuated with the hunter which made Apollo angry. Apollo sent Scorpius to kill Orion. The scorpion scarpered and Orion followed. Apollo tricked Artemis into killing Orion with her bow. Apollo put him along with his dog Sirius into the sky.
The Pleiades are said to be seven daughters of Atlas, the Titan. When Orion started his infatuation for them, Zeus turned them first into doves then stars to keep Atlas company.
Orion thanks to the three stars that make up the belt is one of the most easiest constellations to identify in the night sky. If you are in the northern hemisphere, you just need to look in a southerly direction to spot the constellation.
The constellation contains two of the most famous nebulas, the Horsehead Nebula, to the "south" of Alnitak, so called because at the centre is a dark spot in the shape of a Horses head. The other being the Great Orion Nebula, a beautiful looking nebula.
There are 13 Meteor Showers that occur during the year within this constellation based on information gathered from Adam Mickiewicz University (Poland). The list below are major ones and which I have a date period for.
|Name||Activity||Peak Activity||Closest Star|
|Orionids||October 15-29||Oct. 21||Xi Orionis|
|Is a Zodiac Sign||No|
|Area||594.12 sq. deg.|
|Percentage of Night Sky||1.44%|
|Site Exoplanet Count||19|
|Meteor Shower Count||13|
|Nearest Star||Gliese 205|
|Nearest Star with Exoplanet(s)||HIP 22627|
|Dimmest Star||HD 44497|
|Furthest Star||HIP 27033|
|Bright Star Count||128|
|Hipparcos Star Count||1952|
|Main Star Count||20|
|Messier Deep Space Object Count||3|
|*Non-Messier Deep Space Object Count||1|
|Bordering / Neighbouring / Surrounding Constellations||Taurus|
*Note: The number of Non-Messier Deep Space Object Count relates to how many are covered on this site not how many there are.
|De Mairan's Nebula (M43, NGC1982)||Emission/Reflection Nebula||1600||-05:16||05h 35m 6|
|Flame Nebula (NGC2024)||Emission Nebula||1350 LY||-1d 51` 0.0||05h 41m 54s|
|Horsehead Nebula (NGC2023)||Dark Nebula||1.500||-02:27:30||05h 40m 59m 0s|
|Messier 78 (NGC2068)||Reflection Nebula||1600||+00:03||05h 46m 7|
|The Great Orion Nebula (M42, NGC1976)||Emission/Reflection Nebula||1.324-1.364 kilo||-05:27||05h 35m 4|