ANTARES
The blazing heart of Scorpius—a red supergiant shining through one of the richest fields of reflection nebulae and dark dust in the Milky Way.
Antares is one of the brightest and most recognizable stars in the night sky. It is an enormous evolved red supergiant, much cooler at its surface than the Sun but so physically large and luminous that it shines prominently from hundreds of light-years away.
The star sits in a spectacular region of the Milky Way filled with interstellar dust. In wide-field photographs, Antares illuminates nearby dust with warm golden and orange light while neighboring hot stars produce blue reflection nebulae. Dark molecular clouds weave through the same field, creating the extraordinary color contrast associated with the greater Rho Ophiuchi region.
Antares is also a multiple-star system, with a much hotter companion orbiting the red supergiant. The contrast between the cool primary and blue-white companion is difficult to resolve visually because Antares itself is so bright, but it makes the system especially interesting astrophysically.
The name Antares comes from a Greek expression meaning roughly “rival of Ares,” the Greek god identified with Mars. The name reflects the star’s intense reddish-orange color, which can resemble the planet Mars when the two appear in the same part of the sky.
Antares marks the heart of Scorpius, the celestial scorpion. In one of the best-known Greek traditions, the scorpion is the creature that kills—or is sent to punish—the hunter Orion. The two constellations were placed on opposite sides of the heavens, so Scorpius rises as Orion disappears.
Long before modern astronomy revealed Antares as a red supergiant, its brightness and deep color made it one of the defining stars of the southern zodiac. Its position at the center of the scorpion gives the star an unusually strong connection between physical appearance, constellation shape, and mythology.
Explore Antares in our interactive Stellarium atlas. Find the sweeping hook of Scorpius low in the southern sky; Antares is the brilliant orange-red star at the scorpion’s heart.