Antares is the brightest star in the constellation of Scorpius. It has the Bayer designation α Scorpii, which is Latinised to Alpha Scorpii. Often referred to as "the heart of the scorpion", Antares is flanked by σ Scorpii and τ Scorpii near the center of the constellation. Distinctly reddish when viewed with the naked eye, Antares is a slow irregular variable star that ranges in brightness from an apparent visual magnitude of +0.6 down to +1.6. It is on average the fifteenth-brightest star in the night sky. Antares is the brightest and most evolved stellar member of the Scorpius–Centaurus association, the nearest OB association to the Sun. It is located about 170 parsecs (550 ly) from Earth at the rim of the Upper Scorpius subgroup, and is illuminating the Rho Ophiuchi cloud complex in its foreground.
Antares between τ (lower left) and σ Scorpii; Antares appears white in this WISE false-colour infrared image.
Antares near the Sun on 30 November 2012
VLTI reconstructed view of the surface of Antares A
(July 2008, outdated). Relative sizes of some planets in the Solar System and several well-known stars, including Antares A: Mercury < Mars < Venus < Earth Earth < Neptune < Uranus < Saturn < Jupiter Jupiter < Wolf 359 < Sun < Sirius Sirius < Pollux < Arcturus < Aldebaran Aldebaran < Rigel < Antares A < Betelgeuse Betelgeuse < Mu Cephei < VV Cephei A < VY Canis Majoris
Scorpius is a zodiac constellation located in the Southern celestial hemisphere, where it sits near the center of the Milky Way, between Libra to the west and Sagittarius to the east. Scorpius is an ancient constellation that pre-dates the Greeks; it is one of the 48 constellations identified by the Greek astronomer Ptolemy in the second century. Its old astronomical symbol is (♏︎).
The constellation Scorpius as it can be seen by naked eye (with constellation lines drawn in).
Scorpius and the Milky Way, with M4 and M80 visible near Antares, M6 and M7 just below centre, NGC 6124 at the top of the frame, and NGC 6334 just above centre.
The heart of Scorpius. M4 is visible near the left of center. Portions of the Rho Ophiuchi cloud complex are illuminated by Antares and the other neighboring stars.
Scorpius as depicted in Urania's Mirror, a set of constellation cards published in London c.1825.
