Why is it in the News?

The Bengaluru-based Indian Institute of Astrophysics (IIA) has filmed the passing of the moon in front of Antares, a bright red star.

What is Antares?

• Antares, also known as Alpha Scorpii, is one of the brightest stars in our night sky.
• Located in the constellation Scorpius, Antares has captivated stargazers and astronomers for centuries with its fiery red hue and impressive size.
• The name Antares is derived from the Greek word meaning “rival to Mars” due to its reddish appearance, similar to the planet Mars.
  • Ancient cultures associated Antares with various mythological figures, including the Greek god Ares and the Egyptian god Osiris.
• It is also one of the largest known stars, with a diameter estimated to be around 700 times that of our Sun.
• Antares is located approximately 550 light-years away from Earth, making it a relatively close neighbour in astronomical terms.
•  It is classified as a red supergiant star, belonging to the spectral type M1.5 Iab-Ib.
• Its surface temperature is about 3,500 Kelvin.
• Antares is a variable star, which means its brightness fluctuates over time.
• Scientists estimate that Antares is approximately 12 million years old.
• As a red supergiant, it is in the later stages of its stellar evolution and is expected to explode as a supernova in the future.
• Antares has a mass estimated to be about 15 times that of our Sun.
• It is primarily composed of hydrogen and helium, with traces of heavier elements.
  • Antares has a companion star in a binary system known as Antares B.
  • The two stars orbit each other, with a separation of several astronomical units.
• The visual apparent magnitude of Antares is around 1.06, making it one of the 20 brightest stars in the night sky.
• Antares emits a significant amount of infrared radiation, making it a prominent object in infrared observations.
• Antares experiences intense stellar winds, which cause it to lose mass at a rate of approximately one Earth mass every hundred thousand years.
• Antares played a crucial role in ancient navigation, particularly in the Southern Hemisphere, serving as a marker for determining the position of celestial objects.