In the past few hundred years, only a few supernovas have been observed. The latest of these was observed in 1604. It was also observed and observed well by Kepler.
It is a well-known fact that astronomy fuels other science branches and is essential to understanding the basic laws of nature. As we are endeavoring into the 21st century, we have almost become victims of our worldly needs, and we have even molded our learning according to that. We only study for earning, not for learning. Going against this ongoing trend, here is a pure astronomical article about the ongoing situation at the famous star “Betelgeuse.” Some basic prior knowledge of astronomy is recommended before one reads this article.
Our Sun, with its family of planets, comets, asteroids, satellites, and much more, is situated in a galaxy called the Milky Way galaxy. This galaxy is huge and contains approximately 400 billion stars.
Like any other object in the universe, many of these stars will also die one day, but rather in an explosive fashion called a supernova. Considering the ages of these stars, we do not observe supernovas often. In the past few hundred years, only a few supernovas have been observed. The latest of these was observed in 1604. It was also observed and observed well by Kepler.
This star, which exploded and became a supernova, was 20,000 light-years from us. It appeared as a bright star like Sirius or Venus. But now we are waiting for another star to explode. This is the famous red giant Betelgeuse star, which is about to end its life.
This star, “Betelgeuse,” resides approximately 550 light-years away, relatively much closer than the supernova of 1604. Its reddish color is easily noticeable even with the unaided eye. In the winter sky of Pakistan, it is easily visible in the constellation Orion. This star is a well-known “Red Giant,” having an estimated diameter currently somewhere between 2.5 AU and 6 AU (AU stands for astronomical unit, which is equal to the Earth-Sun distance). Once this star collapses, it will become very small, and all its matter will shatter in space in a spectacular fashion called a supernova.
If it explodes within our lifetime, which we cannot predict, then there will be a great show in the sky. Because it is close to us, it will be shining like a full moon for many days. This spectacular event will be an experience that comes in many millennia. What would the night be like when there would be two moons, so to speak, and light spreading twice that of a full moon?
It might not only look great but also impact other factors related to Earth’s atmosphere and life on it, and it might also disturb our electrical systems too, as a supernova not only gives us light but also bombards us with subatomic particles. These subatomic particles will also have an effect on life on Earth.
In the eyes of some researchers, a new era may begin for our biosphere. There could be huge changes in our plantations and in our marine life that might also impact us, humans, directly. Gamma rays also follow supernova explosions. All these things indicate that this might be an earth-changing event. Most of us, including me, are waiting for it to go boom, but we are all unaware of the harm it may bring with it.
A few years ago, we observed the apparent dimming of the Betelgeuse star. We thought that that was it, and it’s going to explode now in a few days, but that was maybe some ejection of gas stream from the star, which dimmed it. It recovered its brightness in the coming days. We have constant eyes on it in the form of our great telescopes like the ground-based VLT (very large telescope), Hubble, and JWST (from space), and many amateur astronomers like me are also observing it constantly.
Another very important thing that must be mentioned here is that whatever we will observe today has already happened on the star 550 years ago! If we observe it explode in 2024, it had actually exploded back in 1474, the time of almost the end of the Muslim Golden Age of Science.
We will consider everything happening in real time as if we are watching it now because it is understood that we have a lag of 550 years. Also, some astronomers have estimated that it might go boom within the next few tens of years, well within the lifetimes of all those who were born after 1980.
Supernovas in our Milky Way are not common, but they continue to happen in other galaxies. Our universe is filled with billions of galaxies, and in all nearby galaxies, these supernova explosions can be observed even with small telescopes. One thing must be kept in mind: a single supernova explosion gives out that much energy—more than the energy of all normally shining stars in a galaxy!
Yes, that is true—all the stars of the galaxy on one side and this single dying star on the other side. I will quote an example here. We all know the Andromeda galaxy, which is our nearest galaxy. It appears like a small patch of diffused light to the eye. If any supernova explodes in it, we will see that it will outshine its host galaxy!
SN 1885A was a famous supernova in the Andromeda galaxy. It was brighter than its host galaxy, but at that time (1885), astronomers didn’t much notice it. They didn’t even know what it was. I must say we must remain anxious about supernovas not only in the Milky Way but also in nearby galaxies like Andromeda and the triangulum galaxy because such events will be visible even without telescopes.
The Triangulum galaxy is not far from Andromeda in the sky, but in reality, they differ greatly in actual distances. The first supernova yet to be observed in this nearby galaxy!
Astronomy is amazing not only in its simple observational sense but also in its impact on physics. We must pursue our careers in this field.