How many stars are visible and invisible in the sky? What affects the visibility of stars?

In this topic, we will talk about the number of stars of our space.

Content

Our universe is truly beautiful and unlimited. Unfortunately, not all of its beauty we can see with the naked eye. All that is available to us is stars in the night sky. And the scattering of hundreds of bright lights cannot but fascinate. Looking at the starry sky, probably, almost every of us at least once in our life thought about how many stars really. Therefore, in today's topic we will consider this issue.

How many stars are visible and invisible in the sky?

In all centuries, people peered into the night sky, searched for the constellations known according to the legend and tried to imagine that there, in those distant and unknown worlds. And, of course, astrologers have always been looking for the answer to the question of how many stars are in the sky.

Cosmos and heavenly luminaries have always attracted the inhabitants of our planet

For the first time, the stars decided to calculate the ancient Greek astronomer Hipparchus, who lived 2500 years ago. And he not only considered them, but also created a detailed catalog, in which he introduced 1025 heavenly luminaries, distributing them in size and location in the sky.
And now we know that stars exist not only in the sky, but also far beyond its borders. We also understand that they form many different galaxies, and galaxies, in turn, form the Universe, which is endless. We are hard to imagine this. Our mind is not able to evaluate infinity in the form of specific heavenly luminaries. Even if distant lights, but quite material, having gigantic sizes and are colossal energy generators.
All the stars that we have the opportunity to observe the naked eye from the ground are just the microscopic part of our galaxy, which is called the Milky Way and has about 200-400 billion stars.
We can at the same time at the same time on the darkest and best night, somewhere outside the city observe no more than 2-2.5 thousand stars. And the entire heavenly sphere, including the southern or northern hemisphere, gives us the opportunity to see about 5 thousand heavenly luminaries. In the binoculars of stars, you can see significantly more - about 200 thousand, and in a powerful telescope - about 100 million.
Of course, one person does not see such a number of stars at the same time. Only half of this number is available to his gaze. This is due to the fact that the closer to the horizon line, the lower the transparency of the atmosphere. Also, the visibility of stars is lower if you, for example, live in a big city. Often in megacities can only be observed in the sky, only a few tens of star bodies. This is due to the fact that due to excess night lighting and lanterns, there is a lightning that affects the visibility of the stars.

All stars are classified according to quantities, or rather in their visible brightness. The brightest are the stars of the first magnitude, a little less bright - the second size, the weakest in terms of the brightness of the star that we can observe with the naked eye - these are stars of the seventh magnitude. And in a powerful telescope are available for observing a star 29-30 sizes.

With the development of astronomical studies and the creation of new super -powerful telescopes, scientists managed to detect about 100 billion galaxies only in part of the universe accessible for viewing. The largest of them includes 100 trillion stars.
And together according to very rude calculations of astronomers, they can Containing 1’000’000’000’000’000’000’000 Stars - Septilion. Think only in this figure with twenty four zeros! But they are outside the optical range of telescopes! Therefore, talking about the number of stars in the universe is almost impossible, and it is unlikely that this exact figure will be once named.

Their number in the universe is limitless!

What affects the visibility and number of stars?

But returning to the question - how many stars are in the sky - I must also say that the picture of the night sky we observed far from the real image. The fact is that space distances are measured in light years.

For example, the closest star - a proxim of a centaur - is at a distance of 4.5 light years from the ground. This means that on Earth we see her as it was four and a half years ago.
And the closest galaxy to us - a large Maghelane cloud - is located at a distance of 163 thousand light years! For comparison - the light from the sun to the ground reaches only 8 minutes 19 seconds. If we talk about the entire visible part of the universe, then it has incredible sizes calculated in billions of light years!

And not in vain they say - looking at the sky, we look into the past. Because we see not the stars themselves, but only their light, which has reached us in thousands, millions and billions of years. And the stars themselves may no longer exist or they have a completely different configuration. Since each star has its own life cycle - they are born, explode, burn and die, and we see their unfading light for a long time.

Their radiance is a reflection of the past

Flies of exploding stars, called supernova, as well as the stages preceding this process, scientists observe in other galaxies. By cosmic standards, they are fleeting, but by earthly they are quite long.
Since the invention of the telescope, explosions of supernovae have not been observed in our galaxy, but one of the brightest stars visible in our sky - Betelheze, according to scientists, has been in a stage preceding the explosion. However, being at a distance of 560 light years from the Earth, it seems to us as it existed more than half a thousand years ago.
Therefore, it is possible that she has long been gone for a long time, and in the near future we will see the consequences of her explosion, which will illuminate half of our galaxy and in our sky this will affect the appearance of the “second sun”. Although such an option is also possible that in the near future it will explode, and only our distant descendants will see this, after half a hundred years.
The location of the stars in the sky also does not correspond to reality, because when their light came to us, they, if they were alive, managed to shift relative to the earth and each other for a significant amount of light years.

In addition, the part of the heavenly sphere we see is just a projection of stars regarding the point of our location. If we had the opportunity to observe the stars from another planet or from another galaxy, we would see a completely different picture. Therefore, the answer to the question of how many stars in our universe remains open and endlessly unsolved.