I don't know if you still remember, 2020! Betelgeuse has experienced a decrease in brightness visible to the naked eye!
We can see that there is an obvious brightness drop at the lower right! Before darkening, its apparent magnitude was about 0. 1 to 1. 1, but after darkening, its apparent magnitude has dropped to 1.6, which is unprecedented.
People think that Betelgeuse is another dying star, and its shape has been deformed, so when its brightness is found to drop sharply again, people speculate: Is Betelgeuse about to explode? Is our generation about to witness the cosmic wonders of supernova explosions?
But unfortunately, subsequent observations did not find any signs of supernova explosion in Betelgeuse.
On the contrary, since April 2020, the brightness of Betelgeuse has gradually returned to normal! So it seems that Betelgeuse played a huge joke on us, and it is not going to explode!
So since this dimming is not a sign that the kernel is about to go out, what is it?
What did Betelgeuse experience from the end of 20 19 to the beginning of 2020? Why does its brightness fluctuate so much!
For this reason, astronomers have put forward many explanations.
For example, there are huge sunspots on the surface of Betelgeuse, and there are thick dust clouds around Betelgeuse. But without exception, these explanations are not sure that it is the real reason for Betelgeuse's blackening.
No, on June 6, 2002 1616, a new study was published in the internationally renowned scientific magazine Nature, which gave another possible explanation for the blackening of Betelgeuse!
Betelgeuse is a star visible to the naked eye. It is located in Orion, about 724 light years away from the earth!
However, in June 5438 +20201October, a study published in Astrophysics magazine showed that Betelgeuse was only over 540 light years away from the Earth, which was about 200 light years closer than the previous data! I don't know whether this data is reliable. If so, Betelgeuse will have a supernova explosion at such a distance, and I wonder if it will affect the earth.
Its volume has expanded to about one billion times that of the sun! If it is put into the solar system, it can swallow all Mars, Venus and Mercury and reach the orbit of Jupiter!
So in such a huge volume, although it is so far away from the earth, it is also one of the few stars whose disk (surface) we can see.
The stars in our sky are basically stars, but most of them are too far away and too small, so no matter how big the telescope we use, these stars are just a point light source in the lens, and we can't zoom in to see its surface!
But Betelgeuse can!
With the help of the very large telescope of the European Southern Observatory, the researchers took some photos before, during and after Betelgeuse darkened.
They found that the brightness of Betelgeuse darkened not as a whole, but mainly in the southern half of the star surface.
So the darkening of Betelgeuse should be what happened in this area!
20 19, 19 In February, the researchers found that there were huge dust clouds around Betelgeuse, but these dust clouds were too thin to stop the spread of light.
But when the star surface temperature drops, the situation is different!
According to the known detection data, the researchers modeled the dust clouds around Betelgeuse!
They found that when the temperature of Betelgeuse drops, it will cool the dust cloud about 2 billion kilometers away from it. After cooling, the dust cloud will converge and integrate, so it will block the spread of light and reduce its brightness! When the temperature of Betelgeuse returns to normal, these collected dust clouds will be heated again and dispersed, so the brightness of Betelgeuse returns to normal.
Therefore, according to this modeling result, the researchers concluded that Betelgeuse darkened because some substances broke out in the southern half of Betelgeuse, forming dust clouds, which were condensed and aggregated under the action of temperature, thus blocking the spread of light.
Of course, as for the real reason, as we said before, we are not sure yet!
We can't verify the long-range deep space exploration, so the conclusion we get now can only be said to be in line with the current observation data. Maybe in the future, there will be new observation data, so that we can get new conclusions.
But exploration is always like this. We try to find the puzzle of truth through step-by-step exploration. When we get more puzzles, the truth will not be far away!
Well, this is the general interpretation of this research!
I am Teng Bao, a creator of popular science who loves astronomy. Please remember to pay attention.