مجَرَّتُنا ( درب الَّلبَّانة) بها ۱۰۰۰۰۰ ملیون نجم .. كتاب في سبيل موسوعة علمية

Our galaxy (the Milky Way)

It contains 100,000 million stars
And in the sky, there are 1000 million galaxies like our galaxy.

The inhabitants of the sky, the stars, are innumerable in number.

The stars in the sky approach each other, and this results in a group of stars, then another, then another, and so on.

The word "convergent" is almost a profanity in the language of stars, because we know that the closest star to us, to the sun, is about 4.4 light years away, or in miles, it is 4.4 x 6 million million = 4.26 million million miles away.

Convergence, when talking about the stars, carries a meaning other than the one we have gained, and it has vanished in our experience, as human beings, on the surface of this earth, in many dimensions. It's close to the distance. A closeness that remains distant, or a distance that decreases until something of the meaning of closeness enters into it.

The stars when they gather are like the gathering of people on the surface of the earth, small groups, which are included in larger groups, from the tribe, to the people, to the nation.

Binary stars:

When the stars are gathered, they begin with the binary star, which is a single star visible to the eye. The lenses reveal it, and it contains two stars, one of them revolving around the other, or more correctly, that both of them revolve around their center of gravity. There are many binary stars in the sky. Even if you look at the North Star, you think it is one star. Then you look at it with a small telescope and realize that it has a companion from whom Diya was hidden.

- Star clusters:

Then the star clusters, and among the star clusters is the constellation Lyrae, which the sharp-sighted eye looks at and sees that it consists of two stars. You look at it with a small telescope and you see that each of these stars consists of two stars. So it is four stars.

One of the famous groups is the group known as the Pleiades or Seven Sisters. When the human eye looks at it, it is thought that it consists of compact stars, from six to twelve stars. The eye is viewed with binocular telescope
Binocular, you will find more stars in it. According to astronomers, the Pleiades contain more than 200 stars.

These groups are known as open clusters.

(Galaxies are divided into four types. Some astronomers believe that time evolved their shapes, according to the types of stars from which they are composed. The ancient red-colored galaxies formed from condensed clouds of star dust and gas, which helped in their formation in a faster time. And another type of galaxies came together in A mixture of old stars and younger stars, and there is another group in a galaxy that does not have a regular shape and consists of small blue stars and larger amounts of gas and dust.

- The clustered groups:

Among the stellar groups are the well-known groups
Globular Clusters, or if you like, are composed of many stars, as if they were pulled together tightly towards the center of the sphere.

Of course, there must be a reason for the relative closeness between the stars of these star groups, which is undoubtedly due to the law of general gravitation, which was pronounced by the well-known scientist Isaac Newton about three centuries ago.

(The Globular Cluster, which is called Omega Centauri, and these clusters are usually compact and contain tens of thousands of stars. In the Milky Way, there are about a hundred of these, and this particular cluster is about 22 thousand light-years away from us.)

The group of stars known as the Pleiades, and among its stars you can see the clouds, and the light from these gathered stars was reflected back to us.