Why did a Star Suddenly Appear 900 Years Ago?
On the night of sixth August 1181, Sun, Chinese astrology noted that a new start has emerged towards Constellation Cassiopeia. And this new start that emerged was very bright, and its brightness was equal to the brightness of the planet Saturn. They noted it, because they did not know whether the emergence of the star would affect their king or need to wars or if other curses may befall. And this door remains visible for the next months. By February, it dimmed and became invisible.
They did not know why the star appeared suddenly.
Now today, we know that the star witch that Chinese astrologers noted in 1181 is a very rare type of explosion of stars due to which that star emerged in the sky.
A 900 Year Old Mystery Resolve
Today, we know that some stars and their lives in the grand way. This type of ending is called supernova by astronomers, and for a few days or a few weeks or a few months that star (nearing its end) become so bright that it outshines the whole galaxy, which has 200 to 300 bn stars.
Now, in the last 1000 years at least five supernova were visible from the Earth without the aid of a telescope. As you can imagine when people did not know it was supernova it so happened they look towards the sky a new star suddenly became visible.
In fact, there was a famous supernova in 1006 which was noted by a Persian scholar ’bneSina’, and a Egyptian scholar named lbn Ridwan. They did not know it was a supernova, but they saw a new star appearing suddenly in the sky and saw eighths light diminishing after sometime.
There is another famous supernova of 1054. A lot of people saw it from the heart, because it was visible, not only at night. It was so bright it was visible at daytime also for a few months.
Today, we know it was a big star that exploded, and now its remains are in the crab nebula (the gases are with it)
And in the center of the crab nebula, there is a spinning Neutron star also called pulsar which was the core of that star.
Similarly, there were two more supernova whose remnants have been discovered by astronomers. I’ll buy no remnants were discovered of the supernova of 1181. If some star exploded or whatever, happened to something should have remained of it.
Now, after almost 900 years, this mystery has been solved. A new study has been published.
This is an international collaboration and this term name is “Deep sky hunters” it includes astronomers of England, Spain, Hungary, Hong Kong and France. They have detected a nebula named ‘Pa30’ (Patchick 30) and now you are saying its picture in different lights.
And one picture is infrared, one in x-ray, and infrared, and one is in visible light. Is this nebula is almost 7500 light years away from us. And its gases were measured by astronomers they learned that these gases, were expanding at a very fast pace. in fact, the speed of the expansion is 1100 km/s. For example, if you travel at this speed, you will reach the moon in five minutes. The size of nebula is seven light years.
Now, you can calculate that if today this is nebula is 7 ly across and we know the speed of this expansion, then you can know when did it start expanding and this calculation tells us that happened 990 years before that is almost 1000 years. This means whatever happened, it happened at that time, and it is expanding ever since and 100 200 years error bars are included in it.
That is, why the astronomers think that the supernova of 1181 is probably this nebula Patchick 30. The conversation does not in here. This Patchick 30 is a strange nebula, the reason being, it does not have much hydrogen and helium.
Strange Star in the mid of this Nebula
When astronomers saw it in x-ray gas, they detected that a lot of neon, magnesium, silicone, etc are included in it. Also there is blob in the middle which is a little of center. This is a remnant of that explosion.
Its name is Parker’s Star and it is probably a neutron star which is very hot It is a strange star and is one of the hottest star of the Milky Way. The temperature of surface is 200,000°C. If you want to compare the temperature of the surface of our sun is 5500 degrees centigrade.
This is a strange star and there is not much hydrogen and helium present in this star also. This types of stars are called ‘Wolf Rayet Stars’ by astronomers. If you have an interest in astronomy, you can explore it a little more.
But the question is how old it from in the middle of the nebula?
Astronomers think that the supernova off 1181 actually took place because of the collision of two white dwarfs. White dwarfs are when stars like our son reach their end the remains or core is almost the size of our earth
(this is also the future of our sun) and are called white dwarfs by astronomers. The idea is there were two Sun like stars orbiting each other. After their end two white dwarfs remained (also in orbit), earth size stars, and stage of the remains of sun like stars in these white dwarfs were orbiting one another collided and this was the supernova that the Chinese astronomers saw in the sky in 1181.
This type of supernova specially the ones due to collision of white dwarfs are designated as “Type 1AX’ and they are very rare these type of supernova or less than 10%. And this Parker’s stars, it is assumed that the white dwarfs were not finished completely and they are combined form is in a neutron star, and that is the Parker’s star which is very hot. It will eventually keep on cooling.
Suddenly Star Appear:
Now, this is an amazing thing that 1000 years ago, some people look at this sky and they saw the sudden emergence of a star. They did not know why that start a appeared. But they tried to analyze it, what will be its effect on human, or whether it is linked to some wars or curse but actually, this was a collision of two stars (two white dwarfs).
This type of supernova and not only this type, but other types of supernova also are always happening in different galaxies. Whether humans are there or not or whether humans note it or not these types of natural processes are always taking place in the whole universe.
