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The stars in the sky closest to us

The sun is of course the closest star to us. Other than the sun, we find that twenty-few stars in the sky are less than 12 light years away from us. Including, of course, the closest star, Centauri. Among these stars are three of the brightest stars in the sky, but most of these stars are too bright to be seen by the eye without a telescope, despite its proximity.

It is a relationship between the intensity of a star's brightness and its proximity to us or its distance. There is no doubt that the brightness increases the proximity and decreases the distance, but the source of the original brightness is what is in the star that produces light.

(A drawing that shows you how astronomers measure the distance of a star close to the Earth. In the picture from the bottom of the sun, and around it is a circle that is the Earth’s orbit around it. On the orbit are two images of the two positions on the Earth with six months between them. In the first position, the scientists observe the angle of the star. In the second position, they observe the angle of the star. So Scientists obtained the dimensions of the triangle whose vertex is the star, and whose base is after the two earthly positions. As for the two positions, their distances were previously known, and as for the two base angles in the triangle, they obtained them by observing what we have described and by knowing the dimensions of this triangle. They knew the distance of the star.)

- And they assigned ranks to the stars according to their apparent brightness to the people of the earth:

The stars differ in brightness to the eye of the beholder. Some are bright, some are less bright, and some are dim and can barely be seen.

The ancient astronomers used to consider the stars to be ranks, in terms of the light they give to the eye that is apparent to the people of the earth. They are not ranks related to their sizes or weights, or even to the amount of light that emerges from the star where it is from the sky. This is why we called them Apparent Magnitudes. .

They said that the stars of the first rank, then the second, then the third, and so on... and each of these ranks is two and a half times brighter than the next rank. So if we come to the sixth rank, we find that it is a hundred times less bright than the stars of the first rank.

Sixth-ranked stars are the max
The naked eye can see it. Then it is necessary to use a telescope after that. With a telescope we can usually see up to the twenty-third place. They saw its stars with a telescope with a 200-inch mirror.

They placed the stars in ranks according to the amount of light they produce from where they are in the sky:

Astronomers gave the stars their apparent orders. Based on how much our eyes actually see while we are on the Earth's surface. The extent of their luminosity differed, and their apparent levels differed in our terminology.

But these mattresses are not true to what they are
And the reality of its brightness is where it is from the sky. They differ in their distance from us and their proximity to us, so their apparent levels are false levels. As for its levels that are true to those who see it, the true or absolute, as astronomers call it, Absolute Magnitude, there is no way to reach it unless we place them all at the same distance from us, then compare them with what reaches our eyes of their light, and there will be communication.

Astronomers have agreed that this comparison is a situation
All of these stars are at a distance from us equal to 32.5 light-years (they chose this number for a reason related to the angle that the star makes with two positions of the Earth when it revolves around the sun. There is no need to discuss it here). When they knew the distance that the star is from us, and the apparent degree of luminosity, they were able to calculate what the degree of luminosity would be at this distance that unites the stars. So we can give stars
Honest mattresses indicate the reality of their situation.

And our sun, which has the greatest apparent brightness among the stars
Apparent Luminosity, if we placed it 325 light-years away, then a small, weak star would appear to our eyes that we could hardly see with our bare eyes.

The star, called Rigel Man, is one of the stars
The constellation Orion (Gemini), is about 500 years away from us
Optical. If it approached us, like the sun, its brilliance would be 50,000 times as bright as the sun.

Where does the energy of stars come from?

Its source is nuclear energy, in which hydrogen atoms, or if you like, its nuclei, are transformed into helium.
We will explain this in detail in the topic of the sun.
Scientists estimate that the sun “burns” about 564 million tons of hydrogen per second, producing helium, thus releasing energy just as a few thousand millions of hydrogen bombs release when they are detonated.

And we go back and say, “The sun is nothing but a star among stars.”
She is only a small, humble star among them.