As summer settles over the Northern Hemisphere, a striking arachnid emerges in the southern sky—Scorpius, the celestial scorpion, its claws spread wide and its stinger arched to strike. True to its name, it coils across the night in a sweeping “S” shape, its bright stars outlining a form that is unmistakable. It’s no wonder Scorpius has long captivated ancient stargazers. In this blog, we’ll explore the myths that surround this venomous stalker of the night sky, and uncover Scorpius’ most fascinating features, from its brilliant stars to its hidden deep-sky treasures that make it one of the night sky’s most dazzling sights
Mythology and Origins
In Greek mythology, Scorpius was the deadly arachnid sent by the Earth goddess Gaia to strike down the great hunter Orion as punishment for his hunting prowess. The story goes that both were placed among the stars, but cast on opposite sides of the sky—forever separated and never to be seen together. Indeed, as the constellation Scorpius rises, Orion slips below the horizon, as if still fleeing the scorpion’s deadly stinger.
Scorpius is one of the 48 constellations first recorded by the ancient astronomer Ptolemy in the second century and remains one of the 88 constellations recognized today. Scorpius is a zodiac constellation because it lies on the ecliptic, as the Sun passes through it as seen from Earth.
When and Where to Locate Scorpius
- Scorpius is best seen during the summer months, with peak visibility in July and August.
- In the Northern Hemisphere, Scorpius appears low in the southern sky and is easiest to spot from 9 pm to midnight, though it can be seen from late spring through early fall (May through September).
- Look for its distinctive curved “S” shape, resembling a scorpion’s body and tail. Its bright red star, Antares, marks the heart of the scorpion. Scorpius lies along the Milky Way, between the constellations Sagittarius and Libra, making it part of a rich region filled with star clusters and nebulae.
Notable Stars
- Antares: At the heart of Scorpius lies Antares, a brilliant red supergiant binary star with an apparent magnitude of about +1.0. Located about 550 light-years away from Earth, it shines as the brightest star in the constellation and ranks among the brightest stars in the night sky. Antares is easily recognized by its deep reddish-orange color, earning the nickname “rival of Mars” because it can sometimes be mistaken for the red planet when they are visible together. As a supergiant, it has expanded to hundreds of times the size of our Sun. If it were placed at the center of our Solar System, it would stretch far beyond the orbit of Mars.
- Shaula (Lambda Scorpii): The second-brightest star in Scorpius translates to “the stinger” in Arabic and marks the tip of the scorpion’s tail that’s ready to strike. With an apparent magnitude of +1.63, it is a massive blue-white triple star system. Shaula is about 570 light-years away from Earth.
- Lesath (Upsilon Scorpii): Together with Shaula, Lesath forms the scorpion’s stinger. Its name comes from an Arabic word meaning “venomous bite” or “sting,” rather than a direct reference to a scorpion. The fainter of the two blue-white stars, Lesath, has no known companions. It shines at an apparent magnitude of +2.7 and lies about 580 light-years from Earth.
- Dschubba (Delta Scorpii): The brightest of the three stars forming the head of Scorpius, Dschubba takes its name from an Arabic phrase meaning “the forehead” of the scorpion. It is both a binary and a variable star, and astronomers believe it may even be part of a more complex quadruple system. The primary star has an apparent magnitude of +2.29, while its fainter companion shines at +4.62. Dschubba lies approximately 490 light-years from Earth.
- Sargas (Theta Scorpii): The third brightest star in Scorpius. Its name is of Sumerian origin rather than Arabic or Greek, and its meaning is unknown. Sargas is the brightest star anchoring the sweeping curve of the scorpion’s tail. Sargas is a yellow-white giant binary star shining with a luminosity of 960 suns. It has a much fainter companion, Sargas B. Sargas’ apparent magnitude is about +1.87 and is about 300 light-years from Earth.
- Acrab / Graffias (Beta Scorpii): Acrab, also known as Graffias or Beta Scorpii, is one of the bright stars marking the head of the Scorpion. Its names reflect this role: Acrab comes from the Arabic for “the scorpion,” while Graffias means “the claws.” To the unaided eye, it appears as a single bluish-white star shining at an apparent magnitude of about +2.62, and is located roughly 400–500 light-years from Earth. Through a small telescope, however, Acrab resolves into a pair of stars. In reality, it is a complex multiple-star system containing at least five stars bound together in a gravitational dance.
Deep-sky Objects
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Messier 4 (NGC 6121)
Discovered by Philippe Loys de Chéseaux in 1746 and later independently observed and added to Charles Messier’s catalog in 1764, M4 is a bright globular cluster just 1.3° away from Antares, and is one of the easiest globular clusters to spot in the night sky. At a distance of 7,200 light-years away, M4 is also among the closest clusters to Earth. It has an apparent magnitude of +5.6 and is visible in binoculars. Its loose structure lets a small telescope resolve individual stars. M4 is an excellent target for backyard observers. -
Messier 6 (The Butterfly Cluster)
Discovered by the Italian astronomer Giovanni Battista Hodierna before 1654, M6 was independently observed and cataloged by Charles Messier in 1764. It is a bright, open cluster known for its distinctive wing-like shape. M6 is about 1,600 light-years from Earth and shines at an apparent magnitude of +4.2, making it easily visible in binoculars and small telescopes. With a mix of young stars and a distinct pattern, M6 is a popular cluster to observe in the summer sky. -
Messier 7 (Ptolemy’s Cluster – NGC 6475)
First recorded by the Greek astronomer Ptolemy around 130 AD, it was later included in Charles Messier's catalog in 1764, designated M7. With an apparent magnitude of +3.29, it is one of the brightest open clusters in the sky and is easily visible to the naked eye under dark skies. Located roughly 800–1,000 light-years away, it spans a wide area and contains dozens of bright, loosely scattered stars, making it especially striking in binoculars. M7 is also one of the oldest recorded deep-sky objects, first noted by ancient astronomers long before the telescope was used. Its brilliance, size, and rich stellar stars make it one of the most impressive clusters in the summer Milky Way. -
Messier 80 (NGC 6093)
Discovered by Charles Messier in 1781, William Herschel was the first to resolve the cluster into stars. M80 is located about 4° NW of Antares and is one of the densest globular clusters in the Milky Way. It is about 32,000 light-years from Earth and has an apparent magnitude of +7.3. In small telescopes, it appears as a concentrated glow, but it shows more detail in larger-aperture telescopes. -
The Antares Region (IC 4603, IC 4604, IC 4605, and IC 4606)
A vibrant cosmic watercolor in Scorpius, anchored by the red supergiant Antares, this striking region includes both emission and reflection nebulae. The deep red glow arises from emission nebulae, where hydrogen gas is ionized by nearby hot stars, while delicate blue reflection nebulae are interwoven throughout. Located approximately 550 light-years away, this region is part of the larger Rho Ophiuchi star-forming complex, an active environment rich in gas and dust. Although the nebulae have an estimated combined integrated magnitude of around +7 to +8, they span a wide area and exhibit low surface brightness. Their visual splendor is best revealed through long-exposure astrophotography, which captures their vivid colors.
Let’s Go Observing
As you recognize the celestial scorpion sweeping across the sky, it’s easy to see why this constellation has captivated skywatchers for centuries. From the reddish glow of Antares to the glittering clusters and nebulae scattered along its curved shape, Scorpius truly comes alive on warm summer nights, stretching low across the horizon beside the luminous band of the Milky Way. So next time you step outside on a clear summer evening, let your eyes adjust and search for the scorpion. It’s certain that Orion will not be in sight, a quiet reminder of the ancient myth that keeps them forever apart. In that moment, you’re not just looking at a constellation, but connecting with stories that have been passed down for generations and an entire universe waiting to be explored.
Clear skies and happy observing!