What is Antares?

About Antares

• Antares, also known as Alpha Scorpii, is the alpha, or brightest, star in the constellation Scorpius, and the 15th-brightest star in the whole night sky.
• It is a massive red supergiant star.
• It is 10,000 times brighterthan our sun.
• It is one of the largest known stars, 700 times the sun's diameter, large enough to engulf the orbit of Mars if the solar system were centered on it.
• It lies about 600 light-years from the Earth.
• Despite its size, the overall density of Antares is less than one-millionth that of the sun. 
• Antares is also relatively cool as stars go. Its surface temperature is about 6,100 degrees F (3,400 degrees C). That’s in contrast toour sun’s surface temperature of about 10,000 degrees F (5,500 degrees C).
• The star's low temperature accounts for its ruddy color.

What is a Red Supergiant Star?

• They are very large stars that are approaching the later stages of theirstellar life.
• They have a radius that is several hundred to 1500 times that of the Sun. 
• Though they are great in size, the red color indicates that stars of this type have a relatively low surface temperature.
• They are highly luminous.
• Most red supergiants are variable stars. This means, their degree of brightness changes and fluctuates as seen on Earth.
• Also, these stars are actively losing mass. Nebulae have been seen around them as they expel material.

Q1: What is Scorpius?

Scorpius is a constellation known for its distinctive shape and for being one of the 13 constellations of the zodiac, a belt-shaped area of the night sky that the sun, moon, and planets appear to pass through. It is one of the brightest constellations in the night sky. The name is Latin for scorpion, or literally translated as the "creature with the burning sting."With a little imagination, you can see its stars tracing the shape of a scorpion.

Source: Indian Institute of Astrophysics releases video of moon occulting Antares