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The region of sky surrounding Antares, known as Rho Ophiuchus.
Click on image for full size
© Loke Kun Tan (StarryScapes)

Antares - Red Supergiant Star

What's in a Name: Greek for "Rival of Mars" (Ares is Greek for Mars). Sometimes Antares is mistaken for Mars when they are close together because both are red.
Claim to Fame: Brightest star in the constellation Scorpio, the Scorpion. 16th brightest star in the sky (apparent visual magnitude = 0.9)
Type of Star: Red Supergiant (M1 Ib Spectral Class)
How Far Away: 325 light years away
How Big: 300 times as big as the sun (More than twice the diameter of the Earth's orbit).
How Bright: 3000 times the sun's luminosity (Mv = -4.5)
Where to View: In the constellation Scorpio, the Scorpion (Star Map).
When to View: July through August from Northern middle latitudes
Last modified March 25, 2005 by Travis Metcalfe.

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