How many stars can be seen with the naked eye of a person, and how many stars are visible to the nak

There are more than 6,000 stars in the sky seen by the naked eye throughout the day, and they are all stars except for the five major planets in the solar system, meteors, and comets. They are called "stars" because of their relative positions to each other, which are not visible to the naked eye for a long time. Actually, they are all moving, but they are very, very far away from us, and they are imperceptible to the naked eye.

Except for those that have died, stars are all gas spheres, without a solid surface, and the gas relies on its own gravity to gather into spheres. One of the most important properties that distinguishes stars from planets is that they rely on nuclear reactions to produce energy on their own, like the sun, and glow steadily over a considerable period of time. The Sun is also a star.

The other stars, also because they are very, very far away from us, appear to be just a shimmering bright spot. In addition to the Sun, the closest star to us is 270,000 times farther away from the Sun.

People with normal vision can see about 6,000 stars, and if it is the southern hemisphere, it should be a little more. People with extraordinary eyesight can probably see more than 8,000, but it is meaningless to count, you can't count them one by one, and they are generally on the star catalog.

Because the human eye can see infinite distances, there are infinite ones

Venus is the brightest star in the sky, and when it is the brightest, if the conditions are right, such as the horizon height is sufficient, the darkness, the transparency of the atmosphere, and the light pollution is the least affected, it can even shine a human shadow, and it is the only star that can shine a shadow.

In total, there are no more than 7,000 stars visible to the naked eye in the sky.

If we use a telescope, the situation is different, and even with a small astronomical telescope, more than 50,000 stars can be seen.

Stars (stars) are divided into 1st magnitude, 2nd magnitude, and 3rd magnitude stars according to ......their brightness from light to dark. It can be seen with the naked eye as a 6th magnitude star. There are 20 stars of 1st magnitude, 46 stars of 2nd magnitude, 134 stars of 3rd magnitude, 458 stars of 4th magnitude, 1476 stars of 5th magnitude, and 4840 stars of 6th magnitude throughout the day, for a total of 6974 stars.

In fact, due to the influence of moonlight, atmospheric transparency, eyesight, etc., there are generally only a thousand stars that can be seen.

In actual observations, due to the influence of many observation conditions, such as moonlight interference, poor atmospheric transparency, personal vision differences and other factors, the number of stars seen by ordinary people is less than 3,000. The ancient Greek astronomer Epaches was said to have excellent eyesight, and his catalog of stars based on his observations contained no more than a thousand stars. Therefore, when we see the starry sky, we count them carefully, and there are not as many as we think.

On a clear night, the distant canopy hangs twinkling stars, the distance is near or far, the volume is large or small, the brightness is different, the color is uncertain, some are like gems, some are like crystals, twinkle and sparkle are lovely, attracting people's attention.

Stars usually refer to cosmic objects that can be observed with the naked eye without the help of other aid. The shimmering celestial bodies in the night sky, as well as the tiny luminous objects, are all stars. Some stars appear to us to be like spheres and are larger, which may be due to their large size, strong luminous ability, or close proximity to the earth. Some appear to be small dots, which may be due to the small size of the stars, their weak ability to emit light, or their distance from the Earth.

The ancient Greek astronomer Epargos divided the stars into different grades according to their brightness, with very bright stars being rated as first, followed by second, and stars barely visible to the human eye as being of the sixth degree, and fainter stars that could not be seen by the human eye alone.

In this way, we only need to record how many stars there are in each magnitude to know how many stars we can see with the naked eye. Astronomers have done the job: there are 20 stars of the 1st magnitude, 46 stars of the 2nd magnitude, 134 stars of the 3rd magnitude, 458 stars of the 4th magnitude, 1476 stars of the 5th magnitude, and 4840 stars of the 6th magnitude, for a total of 6974 stars.

These nearly 7,000 are all the stars visible to the naked eye on the entire celestial sphere. However, when we look at it from the ground, only about half of the stars are near the horizon, and the starlight weakens even more as it passes through the dense atmosphere, so it is difficult to see the stars in the lower sky near the horizon. In this way, only about 3,000 stars "survived".

So how many stars are visible to the naked eye? This starts with understanding magnitude.

Apparent magnitude refers to the brightness of a star as seen by the observer with the naked eye. Since visual magnitude has no practical meaning in physics, scientists use absolute magnitude to express the luminous power of these objects. Absolute magnitude is the magnitude observed at a place where it is envisioned to be placed at a distance of 10 parsecs (light-years, a parsec is a unit of distance commonly used in astronomy, and one parsec is equal to a light-year).

After experiments, scientists have calculated the conversion formula between visual and absolute magnitude, that is, m=m+5-5logd (absolute magnitude is represented by m, apparent magnitude is denoted by m, and the distance of the star is denoted by the number of parsecs d).

It is known that there are about a few thousand stars visible to the naked eye, but people see far fewer stars for two reasons: first, almost half of the stars are hidden on the horizon and cannot be seen, because the human line of sight is straight and cannot be turned; The second is that the atmosphere is "making trouble", when the weather is bad, there are few stars that can be seen by the naked eye, and when the weather is clear, there are many stars visible to the naked eye.

Stargazing and moon gazing have a long history and are an elegant activity that can be enjoyed by everyone. People look up at the starry sky, express their feelings, and talk freely about their aspirations, so comfortable. However, due to the environmental pollution brought about by rapid development, people can see fewer and fewer stars.

Nowadays, environmental issues have attracted people's attention, and it is believed that as the environment gets better day by day, the bright starry sky will appear again.

1. Astronomer survey: With the naked eye alone, there are 6,974 stars that humans can see. But only half of the starry sky can be seen, so you can count 3,487 stars.

2. In the second century of the Gongsheng Bo Dynasty, the Greek astronomer Epparchus divided the stars in the sky into 1st magnitude, 2nd magnitude, 3rd magnitude star, and so on according to the difference in luminosity. The lower the number, the brighter the luminosity.

3. The faintest star that humans can see with the naked eye is a 6th magnitude star.

According to the astronomical magnitude standard, there are 20 first-magnitude stars, 46 second-magnitude stars, 134 third-magnitude stars, 458 fourth-magnitude stars, 1,476 fifth-magnitude stars, and 4,840 sixth-magnitude stars in the sky, for a total of 6,974 stars.

Considering that humans can only see half of the starry sky, if the eyesight is very good and the night sky is clear and dark, then with the naked eye alone, at the same time, 3,487 stars can be seen.

4. At present, 3487 stars are known to be visible to the naked eye, but people see many fewer stars for two reasons: one is that almost half of the stars are hidden on the horizon and cannot be seen. Because man's line of sight is straight and cannot turn; Second, the atmosphere is "making trouble".

In bad weather, there are very few stars visible to the naked eye. If the weather is clear, there are more stars visible to the naked eye.

6,974 stars are visible to the naked eye.

However, due to some reasons (such as light pollution, air pollution, etc. in the city), there are definitely fewer stars than this, and the number of stars visible to the naked eye in large cities is generally 2,000 to 4,000, which is also seen in complete darkness.

I've looked up to the sky in the past few years, and it's usually less than a thousand stupid forests! Sometimes I only see one or two sentences and a hundred!

We need to protect the environment! Otherwise, only the sun and the moon will be visible in the sky!

The vast majority of stars seen with the naked eye are stars, and only a small percentage are other types of objects. There are about 7,000 stars visible to the naked eye throughout the day, but only about 3,000 can be seen in the same place, and most of them are stars. Only Mercury, Venus, Mars, Jupiter, and Saturn are the only five planets visible to the naked eye.

They are visible most of the year, except for a brief period when they are too close to the Sun to observe. However, all planets are not usually observed on the same night.

Another example is the Cracked, Large Magellanic and Small Magellanic Clouds, which are easily visible in the Southern Hemisphere.

One of the most beautiful galaxies that can be seen is the Andromeda galaxy near our Milky Way, also known as M31, so bright that it can be seen with the naked eye on a dark moonless night.