What is WR-104 and does it pose a threat to Planet Earth?
Discovered only in 1998 poetically named WR-104 is massive star system located in the constellation Sagittarius. It is what is known as a binary star system consisting of a pair of stars orbiting each other. It takes roughly around 8 months for WD-104 (the name of the bigger of the two, WD meaning White Dwarf) and its OB-type partner (name given to a young, blue star) to orbit each other. Both will live for a few hundred thousand years, side-by-side, constantly ripping each other apart. Living this distance in time generally means all the stars are young which causes them to shine a brilliant blue or bluish white. Burning slightly less bright than a full moon, as seen by an observer, this star system has secrets that scientists have rushed to uncover in recent years.
WR-104 joins many other systems with the initials W and R, named after Charles Wolf and George Rayet, two French Astronomers who were the first to discover one of these massive stars in 1867. When these star types are described as massive it really means massive, not the biggest in the Universe but still nearly 20 times the mass of our own Sun. WR type stars have very short lives, in the scope of the universe that is, and exist for just a heartbeat compared to its celestial companions. Once they have used all their nuclear energy they go the same way as all stars by first collapsing in and exploding out. This explosion will release more energy in one second than our Sun will release in its entire life. Wolf-Rayet stars will burn 200,000 times brighter than the Sun due to solar winds that have ripped off its outer layers to reveal the inner core of hydrogen converting into helium gas combustion that burns this bright blue.
The star system is particularly interesting however due to the spiral shape dust remnants that are being dragged behind the orbiting bodies. This occurs because of the two interacting and compressing eachs radioactive material, which was left behind after their birth, causing it to follow the stars in their cosmic dance.
Another point of interest fixed to this star are its poles. Every celestial body has a north and south pole made clearer by its point of rotation or ‘wobble’. The reason why WR-104’s is so interesting is because scientists believe that one of the poles could be pointed straight at Planet Earth. ‘WR-104 is a fascinating object that got a lot of press last spring’, says Dr Grant Hill who works on the Keck Telescope, ‘Since the object is in our galaxy, it could be devastating [for Earth]’. The system is situated 4,800 light years away from the Sun but this is still close enough to be blasted by a Gamma-Ray burst that will be emitted when this star goes Supernova. Supernova is the name given to massive stars when they collapse and explode. This Gamma-Ray burst could stream through the cosmos and rip anything, thats in the way, apart. The radioactive beam would tear layers of the Earth’s crust from the core and deem all life extinct.
It is thought however that previous calculations of the star’s axis being 16 degrees of Earth are incorrect and the sum is now thought to be 30-40 degrees. So WR-104 doesn’t seem to pose as bigger threat than once feared…
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