Are there so many stars in the sky? Or is there a lot of sand on the earth?

The number of stars in the universe or the sand on the earth is a very difficult question, because the number of stars cannot be counted, can only be estimated, even how much sand there is in the hometown, still cannot be counted, and it has to be estimated, therefore, the result must still be an estimate, if there is any inaccuracy, please correct.

Let's start with how many stars are there in the universe?

Humans divide the universe into observable and unobservable, and the observable universe refers to the farthest place that humans can observe with various telescopes, and this radius is about 46.5 billion light years. To make a figurative analogy, a monkey living on an isolated island can see as far as 5 kilometers away, so draw a circle with a radius of 5 kilometers and a monkey as the center of the circle, and the range within the circle is the observable range of the monkey, and the observable universe is also the same.

Then you can draw the following picture vividly, and you will understand it at once.

For the universe, perhaps we only see a finite number of places.

We don't know how big the real universe really is, so here we only estimate the number of stars in the observable universe.

In the past few years, astronomers have relied on the Hubble telescope to analyze how many galaxies there are in the observable universe, which is about 100 billion to 200 billion, and now with more in-depth observations and mathematical calculations, astronomers believe that the previous estimates did not include those fainter galaxies, which account for more than 90% of the observable universe, so for how many galaxies are in the observable universe, this number has suddenly increased by a factor of 10, about 2 trillion.

How many stars does each galaxy contain?

Take the Milky Way as an example, the Milky Way contains more than 250 billion stars, but galaxies are large and small, small galaxies only contain thousands of stars, large galaxies contain hundreds of billions of stars, the gap is too large, and the universe is dominated by dwarf galaxies, such as the local galaxy group, about 50 galaxies, but like the Milky Way, the scale is the Andromeda galaxy, and the smaller ones are triangular galaxies, and the rest are some dwarf galaxies, which are smaller in scale.

Therefore, we can only take a large number of dwarf galaxies as the standard, even if each galaxy only contains 100 million stars, of course, this is a relatively conservative estimate, after all, the number of stars is more than 100 million, and the Milky Way alone can be divided into more than 2500, but here according to a more conservative calculation, then there must be 2 trillion stars in the observable universe.

Next, let's start estimating the number of sand on the earth, some sand grains are large, some sand grains are small, and only the average value can be taken, and not only there is sand on the ground, including rivers, lakes and seas, there will be sand in the rivers, lakes and seas, some people have done calculations, there are a total of 10 16-10 18 grains of sand on the earth, that is, about 100 million billion-10 billion billion, from which it can be seen that it is far less than the number of stars that were previously more conservatively estimated.

And that's just the number of stars that the observable universe may contain, how big is the real universe? It could be much larger than the observable universe, so there are always more stars than sand in the sky anyway.

It's very hard to say, after all, no one has ever ordered it. On the other side of the galaxy, there are many planets, and no one is sure how many there are. And if the sand on the ground is spoken, I don't think any fool will order it.

There are many stars in the sky, and the stars in the sky are about ten to the tenth power, and the sand on the earth is only 10 to 8 powers, a difference of more than 100 times

The stars in the universe cannot be counted, because human beings only know the tip of the iceberg about the universe; The sand on the ground has not been accurately counted, so the two things cannot be compared.

The stars in the sky are the stars that shine.

There are about 100 billion stars in the Milky Way.

And there are about 100 billion galaxies like the Milky Way in the universe, so there are about 10 trillion galaxies.

Almost innumerable. So there are more stars than sand.

I hope it will be adopted, thank you.

This is a question that I will count for you when I get home, and then I will answer you and ask for it.

I think there should be more sand on the ground, because there is too much sand on the ground, there is no way to measure it, and there are many stars in the sky, although there are many of them, but their number is still limited.

This comparison has not yet been concretely measured. But personally, I think there should be more sand than stars in the sky. Because although the universe is large, there are not many stars that we can recognize at present.

I don't know the specifics, but I feel that they are all the same, because there are too many of them, and there is no way to count them and compare them.

Since the question is about the heavens, it means that it is visible to the naked eye, not that it is in the universe, so it is said that there is a lot of sand on the earth, and there are many visible sand in the sky, but the sand on the earth cannot be counted. But if the question is whether there are more stars in the universe or more sand on the earth, then the answer is quite the opposite, because the universe is infinite and the earth is finite.

There are many stars in the sky.

Why: Scientists have come up with the diameter of the universe at 92 billion light-years through existing scientific and technological means. In this vast universe, we know more than 200 billion galaxies.

In the Milky Way, where humans live, there are 2000-600 billion large and small stars. Other galaxies have the same number of stars as the Milky Way, and there are at least 30 trillion stars in the entire universe.

The volume of a grain of sand is about 1 cubic millimeter, and the entire earth is composed of sand, and the maximum estimate is only 100 million, which is a small amount compared to the stars of the universe.

The universe is actually infinite, the universe we can observe is only a part of the universe, in the visual range, the number of stars is so huge, then in the infinite universe, the number of stars will naturally be infinite, but the size of the earth can be measured, the number of sand can also be calculated, therefore, there are still more stars in the universe than sand on the earth.

Normally, the vast majority of the stars we see with the naked eye are stars in the universe.

In fact, the vastness and enormity of the cosmic rift are unimaginable, and stars are only a small part, and mankind knows about nebulae, meteoroids, planets, satellites, comets, interstellar matter, etc., in addition, there are many things that mankind does not know. The number of stars we can see with the naked eye is about 6,000, and the number of stars under an astronomical telescope is difficult to estimate. If you count them one by one, I am afraid that you may not be able to count an accurate number even if you count thousands of years.

Therefore, only one can be calculated.

In fact, whether there is more sand or more stars, some people have long raised questions, and they have indeed been estimated. However, to make this estimate, we must set a premise: the estimation of the number of stars should be within the range of human observation, and the estimation of the amount of sand is the estimation of the amount of sand on the entire earth.

Simon Driver, a well-known Australian astronomer, proposed to estimate the number of planets based on their brightness of light. The age of the universe is about 13.8 billion years, so the number of stars in the measurable range of 13.8 billion light years can be calculated, and the number of stars is 70 000 000 00 7 followed by 22 zeros. Simon Drafer calculated that the amount of sand is about 7000000000 000 000000 000, and 7 is followed by 21 zeros, which means that the number of stars is 10 times that of sand. Within the specified range, the number of stars is greater than the total amount of sand on Earth, but this argument is that all stars are considered stars, and the accuracy of their data has yet to be proven.

In fact, it can also be calculated in this way, the surface area of the earth is 100 million square kilometers, if the thickness of the sand is 10 meters, then: 100 million cubic kilometers = cubic meters; If 1 grain of sand is 1 cubic millimeter: cubic meters; Sand on Earth:

000 000 000 000 000 (16 zeros after 1).

As for the stars in the universe, according to astronomers' estimates, there are about 2 trillion galaxies in the universe, and each galaxy has about 100 million stars, which can be calculated according to multiplication: 2 trillion times 100 million, which is 2x10 (2 followed by 21 zeros).

This method of calculation, in the final analysis, is also an estimate, and its accuracy has yet to be proven, but the difference in the numbers is not necessarily too large. Then, from the above two forms of calculations, it can be concluded that there are still more stars in the universe than there is sand on the earth.

1. The sky without dark clouds is full of bright stars.

2. The dark sky is full of bright stars.

3. The endless sky is full of bright stars.

4. The vast sky is full of bright stars.

5. The sky overhead is full of bright stars.