The October night sky and the return of Orion the Hunter

In the seventh of her popular stargazing series, acclaimed author Omara Williams looks to the October night sky and the majestic return of Orion the Hunter. She shows what to watch for in the coming days – from Orion’s brightest stars and nebulae to the supermoon, meteor showers and planetary pairings

As the clocks go back this month, the longer evenings bring the perfect excuse to step outside, wrap up warm and enjoy the night sky.

Look north and you’ll see the Big Dipper (Ursa Major) sinking low, while Cepheus and Cassiopeia shine high overhead along the hazy band of the Milky Way. The Summer Triangle is still clinging on in the west, although Altair is now slipping towards the horizon.

But look eastward and the show really begins. Bright Capella rises in the constellation Auriga, just to the left of the famous Pleiades cluster and the orange glow of Aldebaran in Taurus. And below them comes the star attraction of the season: Orion the Hunter. Its striking outline is one of the easiest to recognise and a sure sign that winter is on the way.

Orion straddles the celestial equator, so it can be seen from almost anywhere on Earth. Within its boundaries are some of the sky’s most spectacular sights – from the red supergiant Betelgeuse and brilliant Rigel to the Great Orion Nebula, a cloud of dust and gas where new stars are being born.

This month’s guide takes a closer look at Orion: how to spot its brightest stars, the stories behind the constellation, and why it remains such a favourite for stargazers everywhere.

Orion’s Belt

Orion itself is one of the oldest recognised constellations, with references found in ancient Greek, Babylonian, Aboriginal and Egyptian cultures.

In Greek mythology, Orion was a giant, supernaturally strong hunter. The constellation depicts him with a club and shield raised against Taurus the Bull. One myth tells of his boast that he would kill every animal on Earth, prompting the gods to send a scorpion to kill him. Having recovered from the scorpion’s sting, he realised how precious life is and repented of his boast. Then the gods placed him in the heavens on the opposite side of the scorpion, allowing Orion to hide as Scorpius rises.

The most well-known asterism in the Orion constellation is Orion’s Belt. This prominent feature is formed by three bright stars: Alnitak, Alnilam, and Mintaka. These stars are arranged in a nearly straight diagonal line and have similar brightness and distances from each other, making them easy to identify in the night sky.

You can find out how to spot Orion here. 

The stars of Orion’s Belt are siblings, born from the same cosmic nursery, at roughly the same time. All three are spectacular, massive, luminous stars:

1.     Alnitak: The westernmost star, located 1,260 light-years away. It’s a triple star system where the primary component is a blue supergiant about 20 times the mass of the Sun.

2.     Alnilam: The belt’s central star and one of the most luminous stars known. It is a blue supergiant about 40 times the mass of the Sun, located 1,340 light-years away.

3.     Mintaka: The easternmost star, located 1,200 light-years away. It is a unique quintuple star system where the primary component is itself a triple system of massive stars.

It’s been suggested that the pyramids of Giza in Egypt and the pyramids of Teotihuacan in Mexico are aligned with the stars of Orion’s Belt. This alignment holds profound historical and cultural significance for these astronomical bodies, influencing ancient architecture and connecting us to the wisdom and beliefs of our ancestors in a profound way.

The Great Orion Nebula

Below Orion’s belt, there is another prominent asterism known as Orion’s Sword. It consists of several bright stars, clusters and most notably the Great Orion Nebula.

The brightest star in Orion’s Sword is Hatysa, a multiple-star system member of the star cluster known as “The Lost Jewel of Orion”. Just above Hatysa and appearing as the central star of the Sword asterism, you can find one of the brightest nebulae visible to the naked eye and the closest region of massive star formation to Earth: The Great Orion Nebula.

This magnificent nebula is not just a stunning sight in the Orion constellation; within its swirling clouds of gas and dust, new stars are born, offering us a front-row seat to the fascinating process of star formation. Additionally, it is home to several star clusters, including the Trapezium Cluster, which consists of very hot, young stars casting their intense glow on the surrounding cloud walls.

Because of its brightness, proximity, and status as an active star-forming region, the Great Orion Nebula is one of the most intensively studied celestial objects.

Rigel

Rigel, a prominent star marking the left foot of the constellation Orion the Hunter, is a multiple-star system situated approximately 860 light-years from Earth. Rigel ranks as the seventh brightest star in our night sky, making it a significant point of reference in celestial navigation and a prominent figure in various mythologies.

At the heart of this four-star system lies Rigel A, an impressive white-blue supergiant. Rigel A is considerably more massive than our Sun, with an estimated mass around 20 times greater, and it radiates a luminosity that surpasses that of thousands of Suns.

Close to Rigel lies the faint reflection nebula known as the Witch Head Nebula, characterised by its distinctive shape, featuring a long nose and a pointed chin. The walls of the nebula shine with light reflected from Rigel, creating a stunning display that showcases the cosmos’ unique beauty.

Betelgeuse

Betelgeuse is a spectacular red supergiant star glowing on the right shoulder of Orion the Hunter and is the tenth brightest star in the night sky. Located approximately 600 light-years away, Betelgeuse is one of the largest stars visible to the naked eye, with a radius estimated to be over 700times that of the Sun. If placed at the centre of our solar system, its surface would extend beyond the asteroid belt, engulfing the orbits of Mercury, Venus, Earth, Mars, and even Jupiter. As recently as 2024, astronomers confirmed the existence of a much smaller star orbiting very close to Betelgeuse, which was named Siwarha.

Betelgeuse is in the late stages of its life due to its massive size and rapid evolution. It is expected to end its life in a supernova explosion, which will be visible even during daylight and may shine as brightly as a half-Moon for several months. In late 2019, Betelgeuse experienced a significant dimming event, known as “The Great Dimming”. During this event, its brightness dropped by about 60%, due to the star ejecting its outer layers and creating a dust cloud that partially obscured it.

Bellatrix

Bellatrix, located on the left shoulder of Orion, is a massive blue giant star. It has a luminosity thousands of times greater than that of the Sun and is relatively young in astronomical terms. Situated approximately 250 light-years away from Earth, Bellatrix is the 26th brightest star in the night sky and the third brightest in the constellation of Orion, following Rigel and Betelgeuse.

Among the bright stars in the constellation Orion, Bellatrix stands out as the first to appear in the eastern sky around midnight in October. As the hours go by, this striking star ascends higher, revealing the magnificent Orion constellation in all its splendour.

Surrounding Bellatrix is a faint nebulosity illuminated by the bright star aptly named the Bellatrix nebula. The interstellar dust in this nebula reflects the intense, brilliant white-blue light of Bellatrix, giving it a similar blue hue.

Saiph

Saiph is an extremely hot blue supergiant marking the right knee of Orion the Hunter. It is approximately 650 light-years away from us, making it closer than Rigel, although it appears less luminous in the visible spectrum because of its intense ultraviolet radiation.

Saiph is 60,000 times as luminous as our Sun, and approximately thirty times as massive. Rapidly losing its stellar mass as its outer layers are expelled into space, this enormous star is expected to end its life in a dramatic stellar explosion known as a supernova.

Meissa

Meissa is a fascinating multiple-star system marking the head of Orion the Hunter, known for its luminosity, surrounding nebulosity, and role as the central star of the Lambda Orionis star cluster.

Located over 1,100 light-years away, Meissa serves as the apex of a triangle formed by Betelgeuse and Bellatrix. Surrounding this massive blue giant star is a large ring of nebulosity thought to be the remnant of a supernova explosion and known as the Lambda Orionis Ring.

Night Sky Events in October

The Moon shines brightly in October’s night sky, showcasing the Supermoon and a line-up with all the naked-eye visible planets: Saturn, Jupiter, Venus, Mars, and Mercury. An impressive series of appearances, as we shall see below.

October 6 – Moon near Saturn.

The waxing crescent Moon rises in the east after 6 p.m. to the left of Saturn and continues to accompany the planet until dawn.

October 7 – Full Moon (Harvest Moon).

The Moon will reach its closest point to Earth, creating a Supermoon rising on the horizon after 6 p.m. It will appear larger and brighter than any other Moon we’ve seen this year. This visually striking spectacle, with its huge golden glow, is perfect for photography or enjoying the beautiful autumn evening sky.

October 13 – Moon near Jupiter.

The waning crescent moon is visible above Jupiter in the eastern sky after midnight, to the right of the twin stars Castor and Pollux in the Gemini constellation.

October 19 – Moon near Venus.

The thin, waning crescent Moon is positioned to the right and above bright Venus, low on the eastern horizon in the early morning hours after 6 a.m.

October 21 – Peak of the Orionids meteor shower.

Watch for Orionid meteors in the early hours of October 21, starting after midnight until dawn. With the New Moon, the sky will be dark, making it perfect for observing this meteor shower, which features bright fireballs that sometimes rival the August Perseids. Look towards the Orion Constellation, above the bright orange star Betelgeuse. The source of this meteor shower is the famous Halley’s Comet, which orbits the Sun every 76 years.

October 23 – Moon near Mars and Mercury

The waxing crescent Moon is to the left of Mercury and Mars, low on the southwestern horizon as the Sun sets after 5 p.m., making it a challenging sight.

Omara Williams is a nuclear and software engineer whose multi-award-winning debut science-fiction novel, The Space Traveller’s Lover, shot to international bestseller status. Outside of her literary pursuits, she enjoys stargazing and chasing total solar eclipses.

READ MORE: ‘The night sky in September – equinox stars and hidden constellations’. Omara Williams explores the northern sky as the September equinox approaches.

Do you have news to share or expertise to contribute? The European welcomes insights from business leaders and sector specialists. Get in touch with our editorial team to find out more.

Main photo: Osman Özavcı/Pexels