How many stars are in the sky within the currently known universe

The total number of stars that can be seen with the naked eye is only about 6,000, and the number of stars seen through telescopes is much larger. That means:

Are they countless?

Stars are very dense in the Milky Way direction, but relatively few in other directions, which means that we have to abandon the globular stars.

Overall concept. If so, the number of stars in each direction should be as many as the number of stars in the Milky Way direction, and, with the nearer stars, it will be weaker.

The light flickered against the background (not as spectacular as it is now) and the whole sky would be illuminated.

We must assume, then, that the stars exist in large non-spherical clusters and extend farther in the galactic direction than in other directions. Since this is it.

then the Milky Way shows that the stars are clustered into a lens shape or hamburger shape. This lens-shaped cluster is called the Milky Way (from the Greek definition of Milky Way), and the name Milky Way has been retained due to the dark band of light we see surrounding the sky.

The first person to propose that stars exist in occultation galaxies was occultation astronomer Thomas. Wright. He made the proposal in 1750, but he had a good idea.

Like is so confusing and incomprehensible that few people pay attention to him at first. Of course, even if the Milky Way is lenticular shaped, it can always be in the long radial direction.

Extend. Although only a relatively small number of stars are seen on the outside of the Milky Way, there are countless stars inside the Milky Way.

To illustrate, William. Herschel counted the number of stars. Naturally, it is impossible to count all the stars in a certain period of time.

Herschel selected 683 small areas, evenly distributed in the sky, and counted the stars seen with a telescope in each area. With this kind of party.

Law, he got the number of stars in what we now call an "imaginary poll" in the sky. This is the first example of the application of statistics to astronomy.

Herschel believed that the number of stars in each region was related to how close it was to the Milky Way. In all directions, the number of stars increases with the degree of approximation to the Milky Way.

and steady growth. From the number of stars he counted, he could estimate the number of stars in the Milky Way and how big the Milky Way might be. In 1785, he.

The results were announced, and it was proposed that the long diameter of the Milky Way was about 800 times the distance from the Sun to Sirius, and the short diameter was 150 times that distance. Half a century later, days.

The actual distance of the wolf star was calculated, and it was concluded that Herschel believed that the Milky Way had a long diameter of 8,000 light-years and a short diameter of 1,500 light-years. At the same time, he calculated the Milky Way.

There are 8 billion stars in the system. This is a huge number, but it is not uncountable.

In nearly two centuries, astronomers have explored the Milky Way with far better instruments and techniques than Herschel could have used, and now know that the Milky Way is larger than Herschel.

The ears expected to be much bigger. Extending at least 100,000 light-years in the long radial direction, it may have 200 billion stars. However, it can be said that we have confirmed the Milky Way.

And that the stars are not innumerable but calculable, and this is the credit of Herschel.

As much as the sand of the desert.

This is the star of the whole day.

In terms of the number of stars that can be seen by the naked eye, there are no more than 7,000 in total. And since people standing on Earth can only see half of the sky overhead, we usually see only about 3,500 stars. Everyone knows that the stars in the sky are bright and dark.

As early as 2,000 years ago, astronomers lined up the stars according to their brightness, calling the brightest ones "1st magnitude stars", and the slightly inferior ones "2nd magnitude stars" and "3rd magnitude stars", ......The faintest star that can be seen by the naked eye is a star of magnitude 6. In fact, in the entire sky, there are only 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. From the 1st magnitude to the 6th magnitude stars, there are 6,974 in total, and even if you add Mercury, Venus, Mars, Jupiter, Saturn and other planets and the Sun, it is only 6,980.

Of course, this is limited to the stars visible to the naked eye, not the actual number of stars in the sky. The actual number of stars in the Hand Universe is indeed an astronomical number. You just have to look at it with a telescope.

The number of stars in telescopes is exponentially greater than what can be seen with the naked eye, and the larger the telescope used, the more stars can be seen. For example, a small binoculars can see about 7 or 8 magnitude stars; 14th magnitude stars can be seen with a 120 (lens diameter of 120 mm) telescope manufactured by Nanjing Astronomical Instrument Factory; If you use the 5-meter telescope on Palomar Mountain in the United States, you can see 21 magnitude stars, that is, Peiliang, or nearly 2 billion. In fact, even if you use an astronomical telescope with a diameter of 5 meters to observe the stars, you can only see a drop in the ocean.

The stars in the vast universe are actually innumerable. The Milky Way, where our sun is located, is generally estimated to contain 1 5 lo", or about 150 billion stars, and mankind has observed dozens of such "galaxies" by current observation methodsEveryone knows that what is "observed now" is far from the whole universe.

Therefore, in this sense, the stars in the sky are indeed uncountable. ,3,How many stars are there in the sky? How many planets or stars are there in the universe?

If you want to be more detailed, please!

How many stars are there in the sky?

Nature: 30000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

It is often said that the sky is full of stars. How many stars are there in the sky? The answer given by the journal "Nature" published on the 1st is about 3 followed by 23 zeros. For those who like to look up at the stars, counting the stars will be a lot of work.

Peter Van Dowkun, an astronomer at Yale University in the United States, and Charlie Conroy, an astrophysicist at Harvard University, analyzed the intensity of light from galaxies and concluded that the number of galactic red dwarfs was far greater than previously thought.

Previously, astronomers estimated that the number of stars in galaxies was about a trillion times that of 100 billion. This theory is based on the work of Carl Sagan, an astronomer at Cornell University in the United States. Sagan once wrote a best-selling book called "A Hundred Hundred Billion."

He believes that there are 100 billion galaxies in the universe, and each galaxy has 100 billion stars.

After observing distant galaxies in Hawaii with the help of electron astronomical telescopes, Van Dokun and his team found that these distant galaxies were many times or even dozens of times more intelligent than previously thought. "We see 10 to 20 times as many red dwarfs as we do," Van Dokun said. Conroy said that 3 is followed by 23 zeros, which is an astronomical number even for astronomers who calculate distances in light years.

To illustrate the size of the number 23 zeros after 3, Conroy said that each person has about 50 trillion human cells, and there are about 6 billion people on the earth, and the product of the two is exactly 23 zeros after 3. In other words, the stars in the sky are comparable to the total number of human cells on earth.

In addition, Van Dokun and Conroy found that only one-third of galaxies are elliptical like the Milky Way. ,1,

The farthest galaxy that Hubble can see is about 13.7 billion light-years away, and astronomers estimate that there may be more galaxies at 15 billion light-years. This is the boundary of the universe as we know it.

Recently, some astronomers have proposed that the radius of the universe is 46 billion light years.

The Hubble telescope has completed its mission and is about to be replaced by a larger and more advanced telescope, this behemoth with a diameter of 30 meters is jointly developed by the United States, China, India and more than a dozen other countries.

There are more than 300 galaxies in the sky in the sky as large as the moon, and there are about 7 trillion galaxies in the whole day.

According to Einstein's theory of relativity, the universe is "finite and closed", and the universe has no outside.

The total number of planets in the universe is about 1 trillion (1 followed by 20 zeros). We have about 40 billion planets in the Milky Way, and so many of them are so far away that we can't see them, only the galaxy they're in.

There are about 700 trillion stars in the entire visible universe, and he said that this is "the most accurate observation data so far in 2018". Simon Driver, Ph.D. from the Australian National University's School of Astronomical and Astrophysical Studies, reported that his research team used the most powerful astronomical telescope in the world to select a region of space near the Earth for local observations, and then calculated the number. If you want to literally represent this number, you need to add 22 "0s" after the "7".

The list goes on and on. That's true. Our galaxy is home to about 40 billion planets. If you count 10 planets per second.

It takes more than 1,000 years to count without interruption. Therefore, Wang said that it is impossible to count how many planets there are in the universe.

Because so many planets are so far away from us, we can't see them, only the galaxies they are in. It's like we can.

I saw woods several kilometers away, but I couldn't see the leaves clearly.

There are hundreds of billions of galaxies in the universe, and each galaxy is made up of tens of billions of planets. The total number of planets in the universe is about 1 trillion billion.

1 followed by 20 zeros). Keep in mind that this is just an estimate!

There are very, very many planets in the universe, such as the Earth where we live, as well as Ornith, Neptune, Uranus, and Mercury.

1. Oriza is the third largest known dwarf planet in the solar system and one of the two largest objects in the classical Kuiper Belt.

2. Neptune: It is the far solar planet among the eight planets, Neptune is the eighth planet in order of the distance between the planets and the sun, the fourth largest planet in diameter, and the third largest planet in mass.

3. Celestial Scatter Planet: Uranus is the coldest planet in the atmosphere of the solar system, with a minimum temperature of only 49K (-224). The main components of Uranus' atmosphere are hydrogen, helium, and methane. It is speculated that the interior may be rich in heavy elements;

4. Mercury: It is the innermost and smallest planet of the eight planets in the solar system, and it is also the closest planet to the sun.