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This is the constellation, and its name is the first thing worth sorting out. The zodiac sign is Scorpio — Latin scorpio, scorpiōnis — while astronomy keeps a different, equally classical Latin form, scorpius, scorpiī, for the actual stars. Both are genuine Latin words for the same creature; the sign kept one declension and the constellation kept the other, and the split has nothing to do with which is more correct. What the sign and the constellation don't share any more is a location: precession has carried tropical Scorpio about 24 degrees away from these stars, so the Sun is only ever in front of the constellation Scorpius for about a week in late November. Scorpius itself is one of the few constellations that looks like what it's named for — a hooked question-mark of bright stars curling down and back up into a real sting — with the red supergiant Antares burning at its heart like a coal.
Finding it
Look south on a summer evening, low. Antares gives it away: a distinctly orange-red first-magnitude star sitting more or less alone, with Dschubba and the claws curving up and to its right (west) and the long hooked body and tail running down and to its left (east) toward Sagittarius. Scorpius is a summer constellation from Ohio, best placed roughly June through August, highest due south — which for Scorpius is never very high — around late July.
This is the constellation in this set that fights the horizon hardest from 40°N. A star's best altitude, at the moment it crosses the meridian, works out to 90° minus your latitude plus its declination. Antares (declination −26°) tops out around 24° up: low, but workable on any clear night. The claws, Dschubba and Acrab, do a bit better, 27–30°. The tail is where it falls apart. Shaula and Lesath, the sting itself, crest at only about 13°. Sargas and Eta, at the base of the tail's upward hook — stars the site's own chart carries all the way down to declination −43° — top out at barely 7°. The constellation's formal boundary reaches a little further south still, to around declination −45°, which at this latitude works out to roughly 5° of altitude: for practical purposes below the horizon for almost anyone in central Ohio, lost to ground haze and obstructions even on a clear night. That's why so few people here have actually picked out the sting: it never clears the murk near the horizon by much. You need a genuinely open, dark southern horizon, and even then it's a short window around culmination.
The stars
| Star | Bayer | RA (h) | Dec (°) | Mag | Distance | Spectral type | Name |
|---|---|---|---|---|---|---|---|
| Antares | α Sco | 16.490 | −26.43 | 1.06 | ~550 ly | M1.5 Iab-Ib (red supergiant) | Greek Antarēs, "rival of Ares [Mars]" |
| Acrab (Graffias) | β Sco | 16.090 | −19.81 | 2.62 | ~400 ly | B0.5 IV-V | Acrab: Arabic al-ʽaqrab, "the scorpion"; Graffias: Italian, "the claws" |
| Dschubba | δ Sco | 16.005 | −22.62 | 2.29 | ~444 ly | B0.3 IV | Arabic, "the forehead" |
| Fang | π Sco | 15.982 | −26.11 | 2.89 | ~590 ly | B1 V + B2 V | — |
| Alniyat | σ Sco | 16.353 | −25.59 | 2.89 | ~568 ly | B1 III | Arabic, "the arteries" |
| Paikauhale | τ Sco | 16.598 | −28.22 | 2.82 | ~470 ly | B0.2 V | Hawaiian, "house-to-house wanderer" — IAU-approved 2018 |
| Larawag | ε Sco | 16.836 | −34.29 | 2.29 | ~64 ly | K1 III | Wardaman (Aboriginal Australian), "clear sighting" — IAU-approved 2017 |
| μ¹ Scorpii | μ Sco | 16.865 | −38.05 | 3.00 | ~500 ly | B1.5 V + B6.5 V | — |
| ζ² Scorpii | ζ Sco | 16.910 | −42.36 | 3.62 | ~2,600 ly | B1.5 Iae (blue supergiant) | — |
| η Scorpii | η Sco | 17.203 | −43.24 | 3.32 | ~74 ly | F5 IV | — |
| Sargas | θ Sco | 17.622 | −43.00 | 1.86 | ~329 ly | F1 III | Sumerian origin; meaning not preserved |
| ι¹ Scorpii | ι Sco | 17.793 | −40.13 | 3.03 | — | F2 Ia (yellow supergiant) | — |
| Girtab | κ Sco | 17.708 | −39.03 | 2.39 | — | B1.5 III | Sumerian girtab, "scorpion" — the same word behind MUL.GIR.TAB |
| Shaula | λ Sco | 17.560 | −37.10 | 1.62 | ~570 ly | B1.5 IV + B2 IV | Arabic al-šawlāʼ, "the raised [tail]" |
| Lesath | υ Sco | 17.513 | −37.30 | 2.69 | ~580 ly | B2 IV | Arabic, originally "the foggy patch" — see below |
Lesath's name is a documented mistake. The Arabic original, al lat-kha, "the foggy patch," described the naked-eye smudge sitting right next to the star — the open cluster now catalogued as M7. A 16th-century editor miscopied an earlier corruption of that name, "Alascha," into "Lesath," and the error stuck; later astronomers reinterpreted the result to mean "the sting or bite of a poisonous animal," which at least fits where the star sits. Either way, the "foggy patch" it was originally describing is real and worth finding on its own.
Myth and history
MUL.GIR.TAB, Girtab, "the Scorpion," is one of the oldest and most stable constellations in the Babylonian sky, tied to the goddess Ishhara; the girtablullû, scorpion-men, guard the gate of Mount Mashu in Tablet IX of the Epic of Gilgamesh. The fuller religious history, and why Antares's name is observationally earned rather than just poetic, sits on the sign's page, Scorpio; what belongs here is everything outside the Greek and Babylonian frame.
The claws are the clearest case of a constellation losing territory. Ptolemy's Almagest still catalogues the Chelae, the claws, as part of Scorpius, but by his time the Greeks and Romans had already been carving that ground off into its own figure for centuries: Libra, the Scales, whose alpha and beta stars are still named Zubenelgenubi and Zubeneschamali — Arabic for "the southern claw" and "the northern claw." Those names are a fossil: two stars that changed constellations millennia ago, still carrying the address of the one they left.
Outside the Mediterranean, several unrelated traditions land on the same shape for a different reason — not a scorpion, but a hook. In Aotearoa, Scorpius is Te Matau a Māui, the fish-hook of Māui: the demigod's hook, made from the jawbone of his ancestress Muri-ranga-whenua, with which he pulled the North Island (Te Ika-a-Māui) up from the sea before tossing it into the sky, where its curve is still visible in the tail. Related fish-hook readings of the same stars turn up across the wider Pacific, including in Hawaiian tradition, where the tail is Ka Makau Nui o Māui, the Big Fishhook of Māui. The Greek and Polynesian traditions were worked out independently, from the same nine or ten bright stars, and arrived at two different objects doing two different jobs — a stinging tail and a fishing hook — using the identical curve.
The Greek story about Orion is worth taking seriously as more than decoration, because it describes something checkable. A scorpion, sent by Gaia or by Artemis, kills Orion after he boasts he can kill every animal alive; both are placed in the sky at opposite ends of it, so that Orion sets in the west as the Scorpion rises in the east, and the two are never above the horizon together. This is Hellenistic literary catasterism — a story fitted to an existing arrangement of stars rather than the reason for it — but the arrangement it explains is real. Orion's stars sit around right ascension 5h, on the celestial equator; Scorpius sits around right ascension 16.5h, deep in the southern sky — close to twelve hours apart, about as far as two constellations can be. Orion is a winter constellation from Ohio and Scorpius is a summer one. The myth is a genuinely accurate description of an observation anyone here can still make for themselves.
Deep sky
Scorpius sits against the thick base of the Milky Way, so its deep sky is mostly star clusters rather than isolated galaxies. In the tail, M7, the Ptolemy Cluster, is an open cluster of roughly 80 stars about 980 light-years away, bright enough that Ptolemy himself recorded it as a nebulosity "following the sting" in 130 CE — the oldest deep-sky object with a written observation behind it. A few degrees northwest, M6, the Butterfly Cluster, is smaller and more distant (roughly 1,590 light-years), its brighter stars tracing two fanned lobes that give it the name. Both entered Charles Messier's catalogue in 1764; despite sitting close together on the sky, they are unrelated clusters at different distances, lined up only by chance.
Near the claws, M4 is one of the closest globular clusters to Earth — about 6,000 light-years away, and only 1.3 degrees from Antares, an easy find in binoculars once Antares is located. Antares's own light is tangled in dust: it sits at the edge of the same star-forming region that produces the more famous Rho Ophiuchi cloud just over the border, and long-exposure images of the area show the star's red glow bleeding into blue reflection nebulosity thrown off by nearby young stars.
Key dates
| Date | Event |
|---|---|
| c. 1900–1600 BCE | The Scorpion appears in Old Babylonian star material — one of the earliest zodiac figures on record. |
| c. 1000 BCE (contested) | MUL.APIN lists MUL.GIR.TAB, the Scorpion, in the Moon's path. |
| 130 CE | Ptolemy records the cluster later catalogued as M7 as a nebulosity following the sting. |
| c. 150 CE | Ptolemy catalogues Scorpius — still including the Chelae, the claws — in the Almagest. |
| 1764 CE | Charles Messier adds M6 and M7 to his catalogue. |
| 1930 CE | The IAU adopts Delporte's boundaries; the Sun now crosses Scorpius for only about a week, 23–29 November, the shortest solar transit of any zodiac constellation. |
| 2016–2018 CE | The IAU's Working Group on Star Names formally approves Acrab, Dschubba, Sargas, Shaula, Larawag and Paikauhale, several of them non-European in origin. |
Related
- Scorpio (the zodiac sign) — same animal, two Latin declensions, a sign now 24 degrees from its stars.
- Sagittarius — the true neighbour, picking up where the tail ends.
- Libra — carved from Scorpius's claws; its star names still say so.
- Calendar