The Shapely supercluster

In one of the previous posts, we discussed the Great Attactor. In that post, I also mentioned the Shapely Supercluster. This post is going to discuss the supercluster in detail. 

The Shapley Supercluster, also known as the Shapley concentration or SCI, is one of the largest known mass concentrations in our universe. Its mass is at least 10¹⁵ solar masses. This mass includes galaxy clusters and groups like Abell 3558 and Abell 3562. It is located in the north of the constellation of Centaurus.

It is more concentrated than the Great Attractor, and it has an even greater force of gravitation. Its force is so much that even the Great Attractor is being pulled towards it!

I know it sounds so insane.

For better understanding, let us compare it to the Laniakea Supercluster from the Great Attractor post. The size of the Laniakea galaxy supercluster is about 530 million light years. The Shapely Supercluster expands roughly over an area of 600 million light years!

That is it for today. I hope you liked it. If I made mistakes or if you want me to write about anything else, feel free to comment. See you next Sunday!

The colour of the sun: definitely not what you think!

 Have you ever wondered what colour our sun actually is? Is it red, orange or yellow?

What if I told you it is none of these! What if I told you the colour of the sun is actually white. Yes white.

You may ask, why do we see it as red or orange?

Yes, you see it as red or orange because of the scattering of light. You might know that when a beam of white light is passed through a prism, it scatters into multiple colours.

That is exactly how light from the white light from the sun scatters when it passes through our atmosphere. This is called Rayleigh Scattering. 

The amount of light scattered depends on the wavelength of a particular ray. A large amount of blue and indigo waves (shorter waves) get scattered away from the path to our eyes. Red and orange waves (longer ones) don't get scattered in large amounts and reach our eyes. Therefore, they came right to us making it appear red or orange.

However, in the evenings, sunlight has to pass through a thicker layer of the atmosphere. Due to this, this scattering increases and larger amounts of blue light get scattered away. This is why the sky looks red or orange during the sunsets. 

Note: Pictures like the one included in this post are just for demonstration purposes.

I hope you understood this. If you have any suggestions for me please drop them down in the comments. See you next Sunday!!

The great attractor

The great attractor, as we call it is a fascinatingly mysterious region. It has immense mass (equal to that of a 1000 trillion suns!) This mass is so much that it increases the gravitational force of the region, driving it to pull galaxies (including ours) towards it.

Let us dive deep into the mystery.

The great attractor is located in the gravitational centre of the Laniakea Supercluster of galaxies (which includes the Milky Way). Now it is not a single star or a blackhole. Instead, it is a massive concentration of mass. The great attractor is about 150 to 250 million light years away from us.

However, we cannot study it much as it is located in the Zone of avoidance meaning it is difficult to observe it using any telescope. However, scientists are trying to use X-ray and infrared observations to study the Great Attractor. 

But with what we know right we and some other galaxies are being pulled towards it at the speed of 600 kilometres per second!

But, we're not done yet. There is another supercluster called the Shapley Supercluster whose gravitational pull is stronger than that of the Great Attractor. This is why the Milky Way and the Great Attractor, are both getting attracted towards it. 

And now, before you get worried know that we will actually never collide with the great attractor. This is because of the rapid expansion of our universe. The fabric of the universe is expanding faster than the speed of light! So, we would kind of move further away from it reather than getting close.

But the great attractor is still an unsolved mystery.