Antares

Antares, also called α Scorpii, the brightest star in the constellation Scorpio. It is approximately 600 light years from Earth. The name comes from the Greek and means something like "Against Mars ( Gegenares ) ". The god Ares was called Mars by the Romans, and Antares has both a similar color and similar brightness as Mars, which is why both are easily confused, especially as they always are in the vicinity of the ecliptic. Other names are Qalbu l - ʿ Aqrab (Arabic قلب العقرب, Heart of the Scorpion ) and Vespertilio.

Physical Properties

Brightness

With an apparent magnitude of 1.09 like it is the 16th - brightest star in the sky. Its absolute magnitude is -5.3 mag and so is the star in the visible region is about 10,000 times brighter than the sun. The surface is relatively cool, the temperature is only 3,400 Kelvin, which is why Antares has an orange-red color and very much invisible to the eye emits infrared. Taking this into consideration, Antares emits about 65,000 times more energy than the sun. Its spectral class M1, the luminosity class Iab.

Like most red supergiant Antares is a semi- regular variable star of type SRc. The periods are 300 and 1700 days.

Size

From the relatively low temperature and high brightness can be concluded that Antares has enormous proportions. Its diameter is about 1000 million km. He would offset the place of the sun, far extend beyond the orbit of Mars. Antares is one as to the red supergiant Betelgeuse. In its current development phase it loses its outer gas layers, forming a planetary nebula that is visible due to a hot companion star.

Antares has enough mass to form after reaching the helium burning an iron core and explode in a supernova, before he has repelled all gas layers.

α Scorpii B

Antares forms with an unobtrusive companion a double star system. The angular distance of 2.6 " is located at the position angle of 273 °, a blue-white star ( spectral type B3 V) the apparent magnitude 5.5 may order α Sco B 1/370tel has the brightness of Antares, but still has the 170. - times brighter than the sun. the orbital period is 878 years at a distance of 550 AU. to see this companion, a telescope of 10 cm aperture lens is necessary.

Others

Antares can (very rarely) be covered by the planet as ekliptiknaher star from the moon and. The last eclipse of Antares by a planet took place on September 17, 525 BC by Venus, the next will take place on November 17, 2400 by Venus again. Antares is a member of the Gould Belt. In Mesopotamian mythology Antares received in the first millennium BC, the name of the Sumerian goddess Lisin.