Once Khoja Nasreddin was asked how many stars there are in the sky. He replied: This question has interested me for a long time. But I think that it can only be solved if you go up to the sky yourself and count the stars...
The sage was right, albeit partially. Modern satellites and telescopes are discovering more and more distant galaxies, full of countless new stars, and it seems that there will be no end to this... But despite this, the answer to the question is: How many stars are there in the sky? It’s not at all easy to give even to specialists.
Indeed, stars are not distributed throughout the Universe in a uniform “suspension”; they gather into vast groups – galaxies. For example, our Sun is located in the Milky Way galaxy, and in total there are about 100 billion stars. But there are trillions of galaxies alone in the universe!
An ancient sage said that trying to count the stars is equivalent to counting all the grains of sand on all the beaches on the entire Earth. But if we don’t need an exact number, but rather a rough estimate, we can take satellite images, determine the approximate total area of the suitable coastline, find out the average thickness of the sand layer and, knowing the volume of all the sand on Earth, divide it by the average volume of a grain of sand. It's not easy to get a rough figure, but it's possible.
If we return to the heavens, then galaxies can act as such “beaches” for us: it has been approximately established that in our galaxy there are 1011-1012
stars, and there are 1011-1012 galaxies in the Universe. A simple calculation shows that there should be 1022-1024 stars in the universe.
This is, of course, a rough figure, assuming that our galaxy is very average, that there are few deviations from the average, and that we have correctly estimated the number of galaxies in the Universe. And the latter can turn out to be a very deceptive value, because for a long time it was believed that there are about 50 billion galaxies, and only the work of the Hubble orbital telescope increased this figure by 2.5 times!
And even Hubble doesn’t see everything. Apart from particularly distant or dim galaxies, many of them are simply invisible to a telescope operating in the optical range: they are darkened by a dense cloud of gas and dust that accompanies the process of active star formation. The Herschel infrared probe, which is preparing to launch this spring, will allow you to look into these distances (we talked about how it will work in the article “Eyed”).
It is worth considering that no one has ever actually attempted to count the number of stars in a galaxy: usually some general characteristic is measured, in particular, the luminosity of the galaxy. We can then, roughly speaking, divide the galaxy's luminosity by the average luminosity of a star at the same distance - and estimate the number of stars in it. Herschel will work in approximately the same way, “counting” galaxies and measuring their luminosity in the infrared range.
So you just have to wait - until we can say that the stars are no less than the value given above: 1,000,000,000,000,000,000,000,000, that is, a trillion trillion.
People of all times and peoples have long wanted to understand the secret of how many stars are there in the sky. After all, if we can study uninhabited islands, deep depressions and canyons, then why not aim at something more.
Records and tables with calculations have survived to this day, where astronomers carefully recorded the miracles they saw.
Only in the 20th century did people begin to understand some of the principles of stars and their features. But even these discoveries do not explain much. Scientists cannot understand why their mathematical calculations are being broken by more and more new discoveries.
In the 4th century BC. e. Aristotle tried to prove that the stars are motionless. After all, sailors used them all the time as landmarks. There was also a popular belief about a special sphere of stars where the gods lived.
Since the 16th century, the process has become more fruitful. Giordano Bruno revealed to the world that stars are bodies that are very similar to the Sun. In 1596 the world saw a variable star, and in 1650 a double star.
Their work was continued by Kant, Lomonosov, Belopolsky and many others. Gradually they delved into the essence of the stars, their movement and number.
How many stars are there in the sky when you look without equipment?
The first catalog of stars was compiled by Hipparchus about two thousand years ago. He very accurately noted that stars can be divided into categories, namely by brightness. At that time, Hipparchus did not yet have good equipment, but he was able to isolate and record stars up to the 6th magnitude. This data is still used today.
Anywhere on the planet without any equipment we we can see about 5000 stars. All you have to do is raise your head. But it is worth considering the fact that due to the horizon, which covers some of the stars, we will be able to see only 2000.
In big cities, of course, you won’t see such beauty. Many people there don't even notice the stars. Only the brightest units are available to them.
Watching the stars through binoculars - how many stars are there in the sky?
Let's return to the Hipparchus scale. It will give you the opportunity to understand how many stars you can see with this or that device.
Binoculars open order 200 thousand stars. Moreover, this quantity is available anywhere in the world. Ordinary unprofessional telescope increases the number up to 2 million. Next come special telescopes. You can see in them 2 billion. Here many stars no longer have names and are not recorded in star catalogs.
The largest catalog stores the names and photographs of those stars that are visible through a regular telescope, since working with such a quantity is a difficult task. In addition, even in this complete list, most of the faint stars are not named in any way. They are simply photographed.
Of course, there are high-quality photographs where you can immediately see tens of billions of stars. But they are no longer counted. The desired number is obtained from mathematical calculations using knowledge about our galaxy and its neighbors.
- The Sun is the star that is closest to our Earth. And by the standards of the Universe, it belongs to the dwarfs.
- All stars have the same components. Some of them are just younger. Over time they change, becoming brighter and larger.
- Surprisingly, each star is precisely balanced. After all, gravity presses on it, and the internal gas increases. Scientists believe that any balance can be upset. Therefore, stars can explode and go out.
- Because of the amount of energy found in stars, they have different colors. There are more red stars in the Universe.
- The temperature of the star affects the color. Red stars are the coldest. Yellow, like the Sun, is warmer. But the hottest ones are blue.
- Paired stars are the norm. They can only be seen through a telescope. With the naked eye we are presented with only an ordinary bright point. But with the equipment, you can clearly see how the two stars rotate around each other very quickly.
- The larger the star, the less time it can survive.
- Scientists have concluded that there are 500 billion galaxies in the Universe.
- There is no way to reach the stars. If we decide to travel to the closest star after the Sun, then we should think about the fact that we will have to fly for more than 50 thousand years.
Attempts to count the stars in the sky have been made since ancient times. Apparently, it is human nature to systematize and sort everything. The oldest known star catalog was compiled by the ancient Roman astronomer Hipparchus, and this was two and a half thousand years ago. It was he who introduced the concept of “stellar magnitude,” which is still used today. Magnitude is not the size of the star, as the word might suggest. This is her brightness.
Hipparchus divided all the stars according to their brightness into six magnitudes, of which the faintest, visible at the limit of human vision, belonged to the sixth. Then, with the development of optics, the seventh, and the tenth, and the fifteenth magnitude appeared... Such stars cannot be seen with the naked eye at all, only through a telescope of the appropriate power. Through binoculars you can see stars no larger than the eighth or ninth magnitude, by the way.
So how many stars can you see without instruments?
Let's go outside and look at the sky, if it is, of course, clear and clean. The huge number of stars immediately amazes the imagination. But this feeling is somewhat deceptive. In fact, a person with excellent vision will not be able to see more than 5-6 thousand stars in both hemispheres together, and in one - no more than 2.5-3 thousand. This is how many stars with brightness up to 6th magnitude are in the sky.
In reality, we will see much less, and there are reasons for this.
For example, more stars are visible at the zenith, including faint ones. This can be explained by a thinner layer of atmosphere when looking straight up, and therefore less refraction of light and its absorption in dusty and foggy air. Stars closer to the horizon will be less visible. Low to it, we will not be able to see a 6th magnitude star by any means, but it’s good if we can see the 4th. But the area of the sky at the horizon is much larger than the area at the zenith.
In addition, there are many more faint stars than bright ones, and we will only be able to see a small part of them. Therefore, in fact, even a person with perfect vision will be able to see no more than 1.5 - 2 thousand stars in the sky. And this is clearly less than we expected.
It is worth remembering that the more extraneous lighting, the fewer stars are visible. Everyone has been to cities and probably noticed that there are almost no stars visible at all, even in seemingly dark places. So – a few of the brightest ones, and that’s it! The sky is illuminated by street lamps, car lights, thousands of windows... In such conditions, looking at the stars is like looking through a window from a room with the lights on. Also, much fewer stars are visible when the Moon is in the sky, and the brighter it is, the fewer stars are visible.
How many stars are there in total in the sky?
Not only visible to the naked eye, but also invisible? There is no answer here, and there cannot be - the Universe is infinite, there is an infinite number of stars in it, and every second some of them die, others appear. Life is in full swing in the universe, seemingly slow in our understanding, but on what a scale!
It is simply worth noting that with each magnitude, approximately three times as many stars are visible. For example, you can already see about 200 thousand stars through binoculars. The average amateur telescope can already see up to 100 million stars up to magnitude 15-16.
If we go even further and equip ourselves with the most modern instruments invented by man today, we will be able to see a much larger piece of the Universe. We may even be able to see individual stars in other galaxies. Then we will be able to count 70 sextillion stars. This is 7 and 22 zeros!
In fact, as soon as man invents even more powerful devices, the boundary of the visible part of the Universe moves further, and the number of new stars increases many times over. After all, there are an infinite number of stars in the sky!
Since ancient times, people have looked at the night sky and been amazed at how densely it is dotted with stars. The number of shining points in the sky has worried humanity for thousands of years.
Since the times of Ancient Greece, scientists have tried to count the stars, but even now, in the age of high technology and ultra-precise instruments, modern astronomers can only approximately answer the question of how many there actually are.
The first catalog of stars in our history was compiled by the astronomer Hipparchus. Using a primitive telescope, he was able to detect about 1000 celestial bodies in the sky and determine their exact coordinates. It was he who came up with the concept of “stellar magnitudes,” which astronomers use to this day.
The essence of this system is that all objects in the Universe are located at different observable magnitudes - the brighter the star, the smaller its magnitude. Initially, he divided all the stars into 6 magnitudes. The last, sixth, included the least bright ones, which can barely be seen with human vision. Subsequently, scientists discovered many other quantities that were visible only with the help of special instruments.
How many stars are there in six magnitudes? In other words, how many stars can we see at night with the naked eye? It is believed that people with perfect vision see no more than 5-6 thousand simultaneously in both hemispheres.
In one hemisphere, only 2–3 thousand celestial bodies are visible, however, due to artificial lighting at night and a decrease in the transparency of the atmosphere near the horizon in large cities, this number decreases tens of times. With binoculars you can see up to 200 thousand stars, with an amateur telescope - about 10 times more.
The solar system is one of the planetary systems of our galaxy and includes only one star -. All other objects in it are planets, satellites, asteroids, comets and other cosmic bodies. The sun appeared about 4.57 billion years ago and is currently in its prime. 
Its mass is so great that it easily holds near itself and makes all smaller objects move. Unlike other stars, you can see the Sun not at night, but during the day, since at night it disappears below the horizon.
The galaxy in which our planet is located. In addition to the Sun, it supposedly includes 200 billion stars, although some scientists suggest that their number reaches 400 billion. In photographs of the sky taken by the most powerful telescopes, you can see so many stars that astronomers consider it pointless to count them and give names.
Only 0.01% of all the stars in the Milky Way are numbered and cataloged, and even fewer have names - only about 300 stars. As a rule, names are assigned only to the largest and brightest objects, such as Sirius, Polaris, Antares, Proxima Centauri.
Astronomers drew many star names (Aldebaran, Rigel, Algol) from folk tales, parables or legends. Some stars were named in honor of the astronomers who first described them - Bernard's star, Kapteyn's star.
Nobody knows the number of stars in the Universe. It is infinite and in its observable part (visible through the Hubble telescope) contains about a trillion galaxies. There are approximately 200 billion stars in the Milky Way, but there are galaxies that are 20 times larger than ours.
Each of them contains many hundreds of billions of stars, so it is not possible to count them. According to scientists, on average, about 10 24 (10 to the 24th power) stellar objects are available for observation, although it is possible that this number is much higher.
The work of the Hubble orbiting telescope has provided the first hard data to estimate the number of stars in the Universe
The Hipparcos mission has recorded many millions of stars in our galaxy alone - and this is clearly not the limit
The new Herschel telescope will be able to view the most distant stars by their infrared radiation. Its launch, unfortunately, has been postponed year after year, and is currently scheduled for spring 2009.
If you leave the illuminated city streets and look into the sky above your head on a sufficiently dark and cloudless night, it seems like a myriad of stars will open up. In fact, only a few thousand are visible to the naked eye—and even the simplest amateur telescope increases this number by orders of magnitude.
Modern instruments are discovering more and more distant galaxies, full of countless new stars, and it seems that there will be no end to this... But how many are there, after all? Even for specialists it is not at all easy to answer this question. Let's try to figure it out.
Indeed, stars are not distributed throughout the Universe in a uniform “suspension”; they gather in vast groups - galaxies. For example, our Sun is located in the Milky Way galaxy, and in total there are about 100 billion stars. But there are trillions of galaxies alone in the universe!
An ancient sage said that trying to count the stars is equivalent to counting all the grains of sand on all the beaches on the entire Earth. But if we don’t need an exact number, but rather a rough estimate, we can take satellite images, determine the approximate total area of the suitable coastline, find out the average thickness of the sand layer and, knowing the volume of all the sand on Earth, divide it by the average volume of a grain of sand. It's not easy to get a rough figure, but it's possible.
If we return to the heavens, then galaxies can act as such “beaches” for us: it has been approximately established that in our galaxy there are 1011−1012
stars, and there are 1011−1012 galaxies in the Universe. A simple calculation shows that there should be 1022-1024 stars in the universe.
This is, of course, a rough figure, assuming that our galaxy is very average, that there are few deviations from the average, and that we have correctly estimated the number of galaxies in the Universe. And the latter can turn out to be a very deceptive value, because for a long time it was believed that there are about 50 billion galaxies, and only the work of the Hubble orbital telescope increased this figure by 2.5 times!
And even Hubble doesn’t see everything. Apart from particularly distant or dim galaxies, many of them are simply invisible to a telescope operating in the optical range: they are darkened by a dense cloud of gas and dust that accompanies the process of active star formation. The Herschel infrared probe, which is preparing to launch this spring, will allow you to look into these distances (we talked about how it will work in the article “Eyed”).
It is worth considering that no one has ever actually attempted to count the number of stars in a galaxy: usually some general characteristic is measured, in particular, the luminosity of the galaxy. We can then, roughly speaking, divide the galaxy's luminosity by the average luminosity of a star at the same distance - and estimate the number of stars in it. Herschel will work in approximately the same way, “counting” galaxies and measuring their luminosity in the infrared range.
So you just have to wait - until we can say that the stars are no less than the value given above: 1,000,000,000,000,000,000,000,000, that is, a trillion trillion.