Why in the news?

  • Scientists have discovered a rare quadruple star system in our Milky Way galaxy called UPM J1040−3551 AabBab. It is the first known system where two brown dwarfs orbit around two red dwarf stars.

UPM J1040−3551 AabBab

  • What is it?
    • A unique 4-star system:
      • 2 Red dwarf stars (small, common stars that shine faintly but live very long).
      • 2 Brown dwarfs (objects between stars and planets, called “failed stars” because they cannot fuse hydrogen like stars).
  • Features:
    • Red dwarfs are bright enough to be studied so that scientists can estimate the properties of the faint brown dwarfs.
    • Brown dwarfs are about the size of Jupiter, but much heavier.
    • Such systems are extremely rare and chances of low-mass brown dwarfs having companions is less than 5%.

Milky Way Galaxy

  • The Milky Way galaxy hosts our solar system.
  • It is shaped like a flat disc with a central bulge.
  • The Milky Way is estimated to contain 100-400 billion stars. 
  • The inner stars travel faster than those further out. A supermassive black hole called Sagittarius A* is at the centre. 
  • The Solar System is located in the Orion Arm of the Milky Way.
  • Stars like the Sun are rare in the Milky Way galaxy, whereas substantially dimmer and cooler stars, known as red dwarfs, are common.
  • Andromeda is the closest big galaxy to the Milky Way.