What is a Spiral Galaxy?

1 min read
What is a Spiral Galaxy? Blog Image


The Hubble Space Telescope recently captured an image of the spiral galaxy, MCG-01-24-014, revealing the enigmatic beauty of what is known as 'forbidden' light.

About Spiral Galaxy

  • Spiral galaxies are twisted collections of stars and gas that often have beautiful shapes and are made up of hot, young stars. 
  • Most of the galaxies that scientists have discovered so far are spiral galaxies, as opposed to the other two main categories of galaxy shapes—elliptical and irregular.
  • Approximately 60% of all galaxies are thought to be spiral galaxies.
  • The Milky Way, the galaxy that includes Earth and our solar system, is an example of a spiral galaxy.
  • Structure:
    • Most spiral galaxies contain a central bulge surrounded by a flat, rotating disk of stars. 
    • The bulge in the center is made up of older, dimmer stars and is thought to contain a supermassive black hole. 
    • Approximately two-thirds of spiral galaxies also contain a bar structure through their center, as does the Milky Way. 
    • The disk of stars orbiting the bulge separates into arms that circle the galaxy.
    • These spiral arms contain a wealth of gas and dust and younger stars that shine brightly before their quick demise.
  • Spiral galaxies are thought to evolve into elliptical galaxies as the spirals get older. 

Key Facts about MCG-01-24-014

  • It is a galaxy situated approximately 275 million light-years away from Earth in the constellation of Hydra.
  • It boasts a well-defined structure and an extremely energetic core classified as an active galactic nucleus (AGN).
  • It falls under the category of Type-2 Seyfert galaxies. 
  • Seyfert galaxies are any of a class of galaxies known to have active nuclei. They are one of the most common types of active galaxies, sharing the stage with the more distant and luminous quasars.
  • Unlike quasars, whose AGNs can outshine their entire host galaxies, Seyfert galaxies like MCG-01-24-014 allow astronomers to observe both the AGN and the surrounding galaxy.

Q1) What is the Hubble Space Telescope?

It is named in honour of the trailblazing astronomer Edwin Hubble which was launched by NASA. It is a large, space-based observatory, which has revolutionized astronomy since its launch and deployment by the space shuttle Discovery in 1990. Hubble’s domain extends from the ultraviolet through the visible (which our eyes see) and into the near infrared.

Source: Hubble telescope captures 'forbidden light' coming from deep space