A star is about to explode in the sky. His name is Betelgöz. This star is the closest red supergiant to us. It is one of the brightest stars in the sky, thanks to its proximity to the Earth and its huge radius. Betelgöz's first observations and his fame date back to well before the modern age.
We, astronomers, are frankly curious about whether Betelgöz, which has become famous now, will explode as a supernova within this century.
Beteleye, betelgeuse, betelcuz. The original name of the star, which we encounter with different pronunciations, first comes from Arab astronomers. Bat al-jawza, meaning "giant's shoulder", was translated into English as Betelgeuse due to several translation errors in those years. We call it Betelgöz in Turkish. It is also used as the pronunciation of its original name Betelcuz. In the astronomy community, it is cataloged as alpha Ori because it is a member of the Orion Constellation. The prefix alpha here indicates that it is the brightest star in the constellation.
Red supergiant Beteleye is a cold star. Its effective temperature is approximately 3,500 degrees C. Its distance from us is roughly 700 light years. This means that a beam of light from it traveled through space for 700 years and reached us. If we travel at the speed of light, we can only get there in 700 years, which is impossible with current technology. Moreover, it would take approximately 25 million years to reach Betelgöz with a manned spacecraft capable of traveling at high speed.
The mass of Betelgöz is almost 20 times that of the Sun. This value shows us that it will become a neutron star after its supernova explosion. Its radius is approximately 900 times larger than the Sun. The rotation period of this giant around its own axis is almost 30 years. The average duration of the Sun's rotation around itself is 27 days.
Betelgöz is the first star whose surface we can directly image thanks to modern technology. He is in the changing star category. Variable stars show changes in brightness during certain periods. Beteleye is also subject to astrophysical events that change its brightness every 400 to 2000 days.
Towards the end of 2019, the brightness of this crazy star suddenly dimmed more than ever before. Normally astronomers are accustomed to such brightness changes. But the extinction that occurred this time has never been recorded before in history. That's why this event was called the "great extinction". The star reached its faintest state between February 7-13, 2020.
This sudden and large brightness change brought to mind an impending supernova explosion.
If Betelgöz is at the end of this stage, it means that it is nearing the end of its life and a supernova explosion may occur soon. The fact that it was as yellow as Saturn in observations made in ancient Rome, but is now in the red supergiant stage, gives the most important clue about this process.
Recent studies show that Betelgöz is in the final stage of burning carbon in its core. As a result, Betelgöz may explode in a thousand years, it may explode in 50 years, or even Betelgöz may explode tomorrow.
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