Antares is what type of star

Antares is often compared to Betelgeuse , another famous red supergiant, located in the constellation Orion , which lies on the opposite side of the sky. Antares is somewhat larger, but not quite as bright as Betelgeuse. Mars passes near Betelgeuse every couple of years, too, but never gets as close to the star as it does to Antares, and is not associated with it in different tales and myths. In mythology, Orion was stung by a scorpion for being too boastful and the two were placed on opposite sides of the sky, so that they are never seen at the same time.

Orion still appears to be fleeing from the scorpion. Antares is a binary star system consisting of an enormous red supergiant and a smaller but hotter companion. Unlike low-mass stars like our Sun, which stay on the main sequence for several billion years, stars as massive as Antares go through their fuel supply very quickly and, as a result, they reach the end of their life cycle within only a few million years. With an estimated age of 12 million years, Antares is nearing the end of its life and is expected to go out as a supernova within the next million years.

Antares B is four solar radii, making it an average sized star, however Antares A is solar radii, and were it placed in the center of our solar system, its corona would reach Jupiter. Image: Sephirohq at wikipedia.

The companion, Antares B, is a bluish-white fifth magnitude star that lies only about 3 arcseconds away from Antares A and is hidden in the light of the larger star. It has been polluted by matter thrown off by Antares A. The two stars are separated by around astronomical units and have an orbital period of about 2, years.

Antares B belongs to the spectral class B2. Antares B has a luminosity roughly times that of the Sun. Antares B was at an angular separation of 3.

By , the separation changed to 2. Antares B lies approximately astronomical units beyond Antares A, which gives a combined separation of astronomical units. The companion star is buried within the stellar wind of Antares A and can appear green as a result of contrast with the large red star or as a result of mixing of the light when the two stars are seen too close together to be completely resolved.

The mass of Antares B puts the star below the supernova limit. Antares B has numerous unusual spectral lines suggesting it has been polluted by matter ejected by Antares A. Antares B belongs to the spectral class B2. Antares B has a mass of about 7 times that of the Sun. The smaller star has been described as being green, but this may be the result of a contrast effect. The two stars form a binary system and are separated by around AU.

They have an orbital period of about 2, years. Antares is the most evolved star in the Scorpius-Centaurus Association, a nearby OB association, a group of stars that share a common proper motion through space. Antares is the brightest and most massive member of the group. It belongs to the Upper Scorpius subgroup of the larger association. Lunar occultations of Antares are fairly common. The next cycle will begin in Antares can also be occulted by planets such as Venus , though it is very rare.

Antares is nearing the end of its life and is expected to explode as a supernova within the next million years. This will cause an immense supernova explosion, ultimately leaving a tiny neutron star or possibly a black hole. This explosion could happen anytime. The system consists of the red supergiant Alpha Scorpii A, formally named Antares, and a fainter blue-white main sequence star designated Alpha Scorpii B.

Antares has an apparent magnitude that varies between 0. The separation between the stars was measured at 3. The projected separation between the stars is at least astronomical units. The companion is believed to lie more than astronomical units beyond Antares.

Antares has the stellar classification M1. It has run out of its supply of hydrogen and is currently burning through progressively heavier elements. It has an estimated mass about 12 times that of the Sun. Its exact mass is uncertain, but estimates are mostly in the range from 11 to Since evolving away from the main sequence, Antares has expanded to a size of to solar radii. Antares has lost about 3 solar masses of material from its initial mass.

Its estimated age is about 15 million years. With an effective temperature of 3, K, Antares is 75, times more luminous than the Sun. At visual wavelengths, Antares is about 10, times more luminous than the Sun. Its luminosity is dimmed by interstellar dust, but the degree of dimming is uncertain. Antares serves as a spectral standard for its class, which means that its spectrum is used as an anchor point for the Morgan-Keenan MK system of stellar classification, used to classify other stars.

Antares is classified as a slow irregular variable type Lc and its brightness varies from magnitude 0. Type Lc variables are supergiant stars of late spectral types whose brightness typically varies by about 1 magnitude. However, the brightness of Antares usually stays near magnitude 1.

A study of long secondary periods in pulsating red giants did not find a separate long secondary period in Antares. A study of stars belonging to the Scorpius-Centaurus OB association calculated an initial mass of Even if the results vary, Antares is massive enough to end its life as a supernova.

The exact size of Antares is uncertain, but its estimated radius is between and solar radii. The extended outer regions of Antares make it difficult to determine its exact size. A study published in yielded an angular diameter of More recent measurements of the limb-darkened disk gave diameters of The Hipparcos satellite data gave a parallax of 5.

Older estimates were higher than solar radii, making Antares one of the largest known stars at the time. In Polynesia, the constellation has nothing whatever to do with venomous insects. There, the constellation is seen as giant fishhook that the demigod Maui used to snare and pull up land from the sea, that then became the Hawaiian Islands. Home About.