Orion the Hunter, the world’s most recognizable constellation

Star chart of constellation Orion with stars labeled. — Orion the Hunter – visible to both hemispheres – rises in the east on December evenings.

Orion the Hunter is arguably the most recognizable constellation in the world. Orion lies on the celestial equator, making it visible from both the Northern and Southern Hemispheres. Orion’s shape is easy to pick out because of its many bright stars and signature Belt: three stars close together in a nearly straight line.

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Mythology of Orion the Hunter

In many drawings of the constellation Orion, the Hunter looks to be battling his neighbor, Taurus the Bull. Yet there is no such story in the mythology of Orion. Some stories have Orion pursuing the seven sisters of the Pleiades, which is a star cluster in the constellation Taurus. On the other side of Orion are his hunting dogs, Canis Major and Canis Minor. (Not to be confused with Canes Venatici, a different constellation with the actual nickname of the Hunting Dogs.)

Mythology says that a scorpion killed Orion; that’s why Orion is on one side of the sky while Scorpius the Scorpion is on the opposite side. As Scorpius is about to rise in the east, Orion makes a hurried exit from the sky in the west.

Antique colored etching of a man with a raised club holding a dead lion on his other arm. — Orion the Hunter, as depicted in *Urania’s Mirror*, a set of constellation cards from around 1825. Image via Wikimedia Commons.

Brightest stars in Orion

The brightest star in Orion is the bluish Rigel, which marks his western knee or foot. Rigel is a blue supergiant 770 light-years away with a magnitude of 0.2. Rigel is the seventh brightest star in the entire sky. The star marking the other knee or foot of Orion is Saiph, a magnitude 2.1 star. It’s a blue supergiant and 720 light-years distant.

The second brightest star in Orion is reddish-orange Betelgeuse, which marks one shoulder. Betelgeuse is the 10th brightest star in the sky at magnitude 0.5. It’s a red supergiant 430 light-years away and a whopping 800 times larger than our sun. If we substituted Betelgeuse for our sun, it would swallow up all the inner planets.

The third brightest star of Orion, which marks his other shoulder, is Bellatrix. Bellatrix, a blue supergiant shining at magnitude 1.6, is the 22nd brightest star in the sky and 245 light-years away.

Orion constellation over a desert landscape and SUV with people looking up. — View at EarthSky Community Photos. | Parisa Bajelan took this photo on November 17, 2017, from Iran and shared it with EarthSky. Parisa wrote: “Lut Desert is one of the hottest and darkest areas on earth that stretches from the Alborz mountain range in the north to the ocean in the south in Eastern Iran. Lut Desert National Park has many wonders, spectacular wildlife, geo-tourism attractions, well-designed eco-resorts, a marvelous starry sky, and adventure recreation activities as well.” Thank you, Parisa!

Other stars in Orion

Extending out from Bellatrix is Orion’s arm, where he is holding either a shield or an animal, depending on the artist’s concept. The brighter stars marking this object are all of 3rd and 4th magnitude.

Extending upward from Betelgeuse is Orion’s other arm, which holds a club or sword. The brightest stars in the arm and club are all 4th magnitude.

The stars that make up Orion’s head are a test of your sky’s darkness. They range from 3rd magnitude to 6th magnitude. The more stars you can see, the better your skies are.

The three Belt stars from east to west are Alnitak (magnitude 1.8), Alnilam (magnitude 1.7) and Mintaka (magnitude 2.2).

Three white dots in an angled line at top with reddish and lavender gas clouds below. — View at EarthSky Community Photos. | Ken Chan in Portola Valley, California, captured this image of the area around Orion’s Belt on December 1, 2021. Ken wrote: “Headed out on a clear, moonless night to celebrate Orion’s return to the night sky. This constellation is pretty easy to locate with the prominent Orion’s Belt marking the waist of the Hunter. This area is also rich in targets with the Flame Nebula, Horsehead Nebula, Running Man Nebula and Orion Nebula all within the frame.” Thank you, Ken!

Nebulae of Orion the Hunter

The stars in the Sword that hangs down from the Belt are part of the Orion Nebula (M42). You can see the nebula, or cloud of gas, without optical aid as a hazy, 4th-magnitude patch. Using magnification reveals a quadruple star at the center of the nebula. These four newborn stars – the Trapezium Cluster – light up their dusty cocoon, making its glow visible to us here on Earth, a vast 1,400 light-years away.

The famous Horsehead Nebula lies near the Belt star Alnitak. This dark nebula is a faint target even for most amateur telescopes; your best bet is to view it in a picture compliments of an astrophotographer. (Learn more about dark nebulae.)

Along Orion’s side between Alnitak and Betelgeuse (but closer to the belt stars) is the 8th-magnitude nebula M78. M78 has the awkward title of “brightest diffuse reflection nebula in the sky.” One more notable nebula in Orion is near Rigel and crosses into Eridanus the River. IC 2118, the Witch Head Nebula, is extremely faint but also extremely large, spanning six full moons.

Constellation Orion, with a telescopic image of the area around it. — View larger. | Rogelio Bernal Andreo took this long-exposure image of Orion in October 2010. It was the Astronomy Picture of the Day on October 23, 2010. Can you spot all the stars and nebulae listed above in this photo? Image via Wikimedia Commons.

Bottom line: Orion the Hunter may be the most recognizable constellation in the world. It’s visible from the north in winter and from the south in summer.

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