10 billion times the size of the Sun! This star overturns existing theories

10 billion times the size of the Sun! This star turns existing theories upside down

How big is the biggest star? I believe that many friends see here, will think of the shield UY, after all, this star when scientists found it, but very shocked, its volume is up to 450 million times the volume of the Sun, can be said to be very scary, however, in recent years, along with the depth of research, in fact, in our eyes very large shield UY, but not the largest star in the universe.

The UY Shield, which has stepped down from its pedestal,

First let's take a look at this former stellar giant. The distance between UY Shield and this e Earth, about 9500 light-years, if it is placed in the solar system, simply put, is UY Shield if and the Sun change position, then, including Mars, the inner planets of the solar system, will be swallowed at once.

Naturally, the Earth and human beings will not be spared. Fortunately, it is so far away from us that even if a supernova explosion occurs in the future, it will not pose any impact on us.

That said, the reason why Shield is big is that it has entered the end of its life and turned into a reddish special supergiant.

Some of you may be wondering what is. a rete supergiant? For example, we all know that stars go through the red giant stage when they go through the end of their lives, and so does the sun. When the sun becomes a red giant, the sun also expands and reaches near the earth's orbit all at once.

The Sun, however, is not a massive star, so the expansion process that yellow dwarfs like the Sun, or red and orange dwarfs that are smaller than the Sun, go through at the end of their lives is called a red giant.

And massive stars are called red supergiants, or red special supergiants, from which it can also be seen that red special supergiants are the largest kind, and they will eventually become stellar black holes as well.

Generally speaking, the more massive the star, the faster it will evolve. Take UY Shield, when scientists discovered it, it was already in a very unstable state, and studies suggest that in about another 10 to 50 million years, UY Shield, will experience a supernova explosion and then turn into a black hole.

Of course, even if there had been planets and life around UY, they would have been swallowed up the moment UY expanded.

Doesn't it look very scary? At one time in the past, scientists thought that there would be no stars larger than UY in the universe, but as we all know, the universe is very large, and this often leads to things and objects that overturn existing theories or challenge the limits of human perception.

The star Stephenson 2-18, located in the Stephenson 2 cluster, caused the scientific community to boil when it was discovered by scientists, which made scientists feel incredible that this star replaced the king of UY in the constellation of Shield and became the largest star in the eyes of scientists.

Stephenson 2-18 star

Let's first look at the cluster in which this star is located, Stephenson 2, a sparse cluster at the northern end of the long bar structure of the Milky Way. Although it is young, it has a large number of red supergiants inside, and scientists have been attracted to it since 1990 when they first discovered it.

Up to now, scientists have discovered a total of 26 red supergiants in Stephenson 2, and this time the star Stephenson 2-18, which pulled down UY in the constellation of Shield, is one of them.

How big is the star Stephenson 2-18? According to the data, it is large about 10 billion times the size of the Sun. Some of you may not have an accurate idea, so let's compare it with the Earth.

Simply put, it is the star Stephenson 2-18, which can fit about 130 billion Earth, so you can imagine how big it is, and how scary it is.

At the same time, the diameter of Stephenson is 2-18, also about 2150 times the Sun, which means that basically half of the solar system will be completely swallowed by it.

Of course, as we mentioned above, the larger the star, the shorter its lifespan will become, and naturally, Stephenson 2-18 will soon undergo a supernova explosion and eventually become a stellar black hole.

Of course, not only Stephenson 2-18, in the vast universe, there are many stars larger than UY Shield, such as another star scientists are very concerned about - WOH G64.

The first candidate: WOH G64

WOH G64 is located in the Large Magellanic System, and it is a red special supergiant star like UY in the constellation of Shield. According to studies, WOH G64 is about 2000 times the diameter of the Sun, and from this point of view, the star WOH G64 seems to be smaller compared to Stephenson 2-18.

However, some researchers believe that the observations of WOH G64 may not be accurate, and many believe that in the future, WOH G64 will probably pull Stephenson 2-18 down from the largest star and become the largest star in the universe, of course, with a "known" in front.

At present, WOH G64 is also at the end of its life, and like UY Shield, WOH G64 is also very unstable, and it may soon experience a supernova explosion and become a stellar black hole.

Of course, fortunately, these stars are very far away from us, so naturally, we can study and enjoy them as much as we want here on Earth, without worrying that one day in the future when they undergo a supernova explosion, they will plunge us into a huge disaster.

What is a stellar black hole?

In the above article, we have often mentioned a word: stellar black hole, so let's take a look together, at what is a stellar black hole.

Modern scientific research suggests that if the mass of a stellar predecessor can reach 20 times the mass of the Sun, then, at the end of its life, after a supernova explosion, the star will internally gravitationally collapse and become a stellar black hole.

Of course, this concept is also the conclusion of researchers based on the study of the evolution of stars in the universe, as well as the observational study of black holes, etc. Likely, stars that are less than 20 times the mass of the Sun may also evolve into stellar black holes.

The number of stellar black holes is very large, in the galaxy, according to estimates of the number of stellar black holes, it is about hundreds of millions. At present, scientists have discovered the largest stellar-class black hole in the universe, it is LB-1, this black hole was discovered by Chinese scientists in the year 2019.

Generally speaking, the mass of a stellar black hole is not more than 100 times the mass of the Sun, however, in fact, scientists have rarely found a stellar black hole with a mass more than 60 times the mass of the Sun.

So scientists were thrilled when stellar black hole LB-1 emerged, with a mass 70 times that of the Sun, making LB-1 the king of known stellar black holes.

And, before the stellar black hole LB-1 was discovered, in fact, scientists once thought that the maximum mass of stellar black holes, but only about 65 times the mass of the Sun, when LB-1 appeared, it also overturned the existing stellar black hole theory, can be said to help mankind for stellar black holes, once again a new understanding.

Of course, LB-1 will not be the largest stellar black hole in the universe, let's say that last year scientists discovered a special black hole based on research that overturned the existing black hole size theory, the mass of this black hole is more than 140 times the Sun and so on, it also became a new type of black hole - an intermediate-mass black hole.

In the future, as research progresses, perhaps LB-1 will one day be pulled down as the "king of stellar black holes", just like UY in the shield.

So, since scientists have discovered more and more supermassive stars, have they found the smallest stars in the universe as well?

Which is the smallest star in the universe?

Many friends may think that the smallest star in the universe is also larger than the planets, after all, in our impression, the planets are affected by the gravity of the star, around the star, if the star is smaller than the planets, then, soon will lead to the inability to bind the planets around it?

The answer is no because scientists have found the smallest star, which is smaller than Jupiter, with a diameter of only 0.09 times that of the Sun. The name of this star is 2MASS J05233822-1403022, which is located 40 light-years away, so it is not far from Earth.

It is also the smallest star known to man up to now, and it is also one of the most common red dwarfs in the universe, which has also become a key object of observation for scientists since it was discovered in 2014.

If 2MASS J05233822-1403022 were any smaller, it would be a brown dwarf, that is, a failed star, between a star and a planet, making it a special kind of object.

However, it happens to be in the range of critical values today, which makes it one of the most extraordinary existences in the universe, knowing that its surface temperature is only 1800 degrees Celsius, which is even lower than the temperature of some hot Jupiters.

Seeing this, some of you may be wondering how much of the Sun's mass is generally reached to become a star. The answer is 7% of the Sun's mass, which means that if a planet's mass, can reach 7% of the Sun's mass, then, it will become a star, even if the volume to see, is smaller than the planet.

Of course, this does not mean that 2MASS J05233822-1403022 will be the smallest star in the universe, after all, human understanding of the celestial bodies in the universe is still in its infancy, but, because small masses of stars are generally very faint, and very difficult to find, so, for a long time to come, the smallest star record holder, will be 2MASS J05233822-1403022 for a long time to come.