Secrets of Blue Supergiant Stars

               A blue Supergiant star(artist's view).                                                                                                      Astronomers study the nature of Blue Supergiant Stars for decades. Blue Supergiants are difficult to study because they have a short lifetime as they die young. Stars temperature are determine by their colour - Blue Supergiants are hottest while Red stars are the coolest. Blue Supergiants have a surface temperature between 20,000℃ to 50,000℃.                                                                                           Blue Supergiants are the final burning phase before the death of a super massive star in Supernovae. Research are limited on these giants due to unavailable technology and equipments because telescopes can't see the interior of stars. 

        

 The illustration in this video shows the waves generated in the interior of a star.                                                                             Recently, a team of Astronomers from Belgium and England, revealed many facts after observing Supergiants from 5 years. They published their results in Journal Nature Astronomy. They create simulations and models of interior of these Supergiants.                                                                                          Blue Supergiants can turn into Red Supergiants near the period of supernovae. Blue Supergiants have a mass nearly 20 times to that of Sun and gives out as much energy as given by 60,000 Suns. They are the brightest stars of the night sky in which Rigel is most known to us, it is also the brightest star in Orion constellation.                

                 

      Seismic waves travelling in Supergiants.                                                                                                          Using Astroseismology to study Blue Supergiant Stars.                                                                                                                                                                                                  'Astroseismolgy is a similar to seismology - used to understand Earth's interior by Seismic waves in Earthquakes. Dr. Tamara Rogers and her colleagues of Newcastle University study Blue Supergiants by two waves, Gravitational waves which breaks at the surface of stars - similar to waves at shoreline and second is wave generated in the interior of the star - similar to Seismic waves generated in the interior of the Earth. Together with KU Leuven in Belgium Dr. Rogers find that the shimmer and ripple in brightness is due to presence of waves on the surface of star.

                                                                                                             Size difference between Rigel and Sun.                                                                                       " The discovery of waves in so many Supergiants stars was a eureka moment" added Bowman. Waves helped Astronomers to understand movement, rotation, physics and chemistry of stars interior including stellar core. Astronomers also listen symphony of sounds generated by stars to unlock their interior.                                                     Blue Supergiants are the metal factory of the Universe, they produce all elements except helium in periodic table of Mendeleev before supernovae. "We are now entering in golden age of Astroseismology of hot massive stars thanks to modern space telescopes. The discovery of these waves in Blue Supergiants allows us to study the prognitors of supernovae from a novel prespective" says Dr. Bowman.