Why are the sun, the earth, and the moon all round?

Universal gravitation. If not affected by external forces, all objects have a tendency to concentrate towards the center under the action of gravitational force. The most concentrated knots.

It's spherical! Although the surface of the earth is solid, because solids are also deformable, and solid fragments can move, these.

all make it possible to transform it into a spherical shape.

The activity of energy in the Earth's interior makes the Earth irregularly shaped. However, the stones of the mountains are rolled down from a high place by the gravitational pull of the earth (gravitational pull), and the rivers carry the sediment from the high to the low-lying oceans (the rivers also flow by the gravitational pull of the earth)...These are all examples of concentration towards the center, and they all turn the earth from irregular to spherical.

If the Earth's interior ceases to move, it is possible that in many billions of years the Earth will become a very standard spherical shape (with the exception of centrifugal force and the gravitational pull of other celestial bodies).

Many asteroids, due to their own small mass, resulting in their own gravitational force is relatively small, and the star is generally composed of relatively hard solid rock, it is difficult to complete the process of moving to the center under the action of its own gravity, so their shape is strange, oval, rod-shaped. Many.

Vernacular commentary: It means that these stars are rounded because gravity attracts meteorites!

It is the effect of gravity, the larger the celestial body, the greater the gravitational force, and the more round it is, so the sun is very round, and the earth is just an ellipse.

Because God has trouble pinching other shapes, and you have to pinch so many stars, so it's all round.

Because what you see is round.

Because the earth, the moon, and the sun all have a large gravitational pull that attracts objects on the surface of the sphere close to the center, they are all round.

Because the gravitational pull is greatest in the interior of each planet, it compresses the surrounding matter towards the center and becomes a circle.

This is because of the gravitational pull that exists on these stars, as well as the pressure in the atmosphere, which causes these forms to be round.

The moon is a satellite of the earth, and it is the only earth satellite, the diameter of the moon is 1 4 of the earth, among all the eight planets in the solar system, the diameter of the planet 1 4, only the moon is one, the diameter of the other satellites is very small compared with the planet, with many moons. Like Saturn, there is a belt that is not so much thousands of moons as thousands of pieces of rubble. At the beginning of the birth of the earth, it was also like Saturn, and after a long period of evolution, part of it fell to the earth, and part of it was annexed by the moon, and developed into the current earth-moon system.

We looked up and saw a beautiful moon in the sky. Therefore, 4.5 billion years ago, when the earth was born, there was no moon, and the moon is just a celestial phenomenon now.

<> the Earth and the Moon.

Saturn. <>

Saturn. The sun, the earth, and the moon are circular because they all rotate.

The shape of the moon is the same as that of the earth's sun, which is a circle, and the moon is the only natural satellite of the earth.

1. Both the Moon and the Sun are spherical celestial bodies. The waxing and waning of the moon that we see is determined by the position of the sun, the earth, and the moon.

2. The moon revolves around the earth, and the period is about days, and because the earth revolves around the sun, the period of the moon phase change is greater than days, about days. On the first day of the lunar calendar, the moon runs between the earth and the sun, so the moon cannot be seen on the earth, which is called "Shuo" or "crescent moon and rock"; Half of the moon can be seen on the seventh or eighth day of the first month, the east is dark, the west is bright, and it is called the "first quarter moon"; At fifteen or sixteen o'clock, the moon moves to the far side of the earth, and the mausoleum can be called to see the round moon hanging high in the sky, which is called "full moon" or "hope"; Around the 22nd, the western half of the moon is dark and the eastern half is bright, which is called the "last quarter moon". The moon is a cycle from the first quarter of the new moon, the full moon to the second quarter of the moon, which is called a lunar month.

The relationship between the Sun, the Moon, and the Earth is:

All three are stars of the solar system and belong to the same solar system.

The Earth revolves around the Sun.

The moon revolves around the earth, and the two form the earth-moon system, and the two revolve around the sun at the same time.

The Sun is the central body of the solar system and occupies the overall mass of the solar system. The eight planets, asteroids, meteors, comets, outer Neptune objects, and interstellar dust in the solar system all revolve around the sun, and the sun revolves around the center of the Milky Way.

Earth is one of the eight planets in the solar system, the third planet in order from near to far from the sun, and it is also the largest pre-mesoterrestrial planet in the solar system, with a distance of 100 million kilometers from the sun.

The Moon, popularly known as the Moon, is the Earth's only natural satellite and the fifth largest in the solar system.

Question 1: Which is the largest sun, earth, or moon The sun is the largest.

If you compare the sun to a sack of rice, the earth is the size of a grain of rice.

The second is the earth.

Finally, there is the Moon with a radius half that of the Earth.

Question 2: What is the biggest size of the earth, the sun or the moon? The sun is at its maximum.

Question 3: Who is the biggest in the sun, earth, and moon The sun is bigger than the earth, and the earth is bigger than the moon.

Question 4: Look at the Earth, the Sun and the Moon Who's bigger Looking at the Moon from the Earth, it looks about the size of the Sun, creating the illusion that the illusion is a strange arrangement of distances.

The diameter of the Moon is 3,476 kilometers, and the diameter of the Sun is 10,000 kilometers, which means that the diameter of the Sun is 400 times that of the Moon. But the distance from the earth to the sun is 149.6 million kilometers, and the distance from the earth to the moon is only 384401 kilometers, and incredibly, the distance from the moon to the earth is exactly 1 400 of the distance from the earth to the sun, so from the earth, the moon and the sun are about the same size, so that the moon is exactly in a position where a total solar eclipse can occur, and the moon is not big or small, and it coincides with the sun accurately. Astronomers call this strange phenomenon an "astronomical accident" because it cannot be explained by astronomical principles.

Question 5: The sun and the moon are bigger Objectively speaking: the volume of the sun is larger than that of the moon.

The earth revolves around the sun, and the moon revolves around the earth. If you say it subjectively: since the moon is relatively close to the earth relative to the sun, the fifteenth lunar calendar of each month will make people feel that the moon is bigger.

The Sun: its volume is more than 1.3 million times that of the Earth, with a diameter of 1.39 million kilometers, and the Moon: the volume is only 1 49 times that of the Earth, with a diameter of about 3,476 kilometers.

Question 6: Which is bigger or farther, the Sun or the Moon? How far away are they from the Earth The average distance between the Sun and the Sun from the Earth is 149.6 million kilometers, and the average distance between the Moon and the Earth's plains is 384,401 kilometers.

1.The trajectory of the Moon.

The Moon is a natural satellite of the Earth, and it orbits the Earth. At the same time that the Moon is moving around the Earth, the Earth is also moving around the Sun. The Moon's trajectory around the Earth is elliptical, and its orbit is somewhat tilted, so the Moon appears sometimes closer to the Earth and sometimes farther away from the Earth.

And when there is a moon and the sun, the moon will take different shapes, which is the moon phase.

2.The relationship between the Moon and the Earth.

The Moon is a natural satellite of the Earth, and there is a gravitational force between the Moon and the Earth. This gravitational action leads to the emergence of tidal phenomena. In the process of the moon's motion, the gravitational pull of the moon is always opposite to the center of the earth, and the moon with an elliptical orbit is farther away from the earth at one end of the orbit, the gravitational pull is less, and the gravitational pull of the earth is also less, so the ocean at that end forms the so-called tidal uplift.

At the other end of the orbit, the Earth's strong gravitational pull deforms the Earth, and the ocean recesses into the so-called tidal fall.

3.The formation of the phases of the moon.

The positional relationship between the Moon and the Sun affects the brightness and shape of the Moon, which is the moon phase. When the Moon is right between the Earth and the Sun, we see the far side of the Moon, which is black and is called the Crescent. As the Moon passes between the Earth and the Sun, the brightness of the Moon as seen gradually increases, until the Moon is on the opposite side of the Sun, when we see a Full Moon, at which point all the positive sections of the Moon are illuminated.

After the bend is burned, the moon goes from full moon to new moon, and this cycle is a moon phase.

4.Lunar and solar eclipses.

The positional relationship between the Moon and the Sun not only affects the brightness and shape of the Moon, but also produces lunar and solar eclipses. A lunar eclipse is a phenomenon that occurs when the Moon moves between the Earth and the Sun, and the Sun is obscured by the Moon; A solar eclipse is when the Moon is located exactly between the Earth and the Sun, and the Moon blocks out the Sun's rays and creates a shadow on the Earth. These two phenomena were considered bad omen in ancient times, but modern science can already explain the mechanism of their occurrence.

5.Exploration and use of the Moon.

The moon is one of the objects of human research, and since the 60s of the 20th century, countries have carried out many explorations of the moon. The most representative of these is the Apollo program of the United States, under which the first human landing on the moon was realized. In addition, the Moon is also considered a potential base for future space exploration, as there are some materials and resources on the Moon that have potential future utilization.

For example, scientists believe that the moon's oxygen, water, iron and other resources can provide energy and materials to support human exploration of space.

6.Summary.

The relationship between the position of the moon and the sun affects the shape and brightness of the moon, and also affects the occurrence of tidal phenomena on the earth and natural phenomena such as lunar and solar eclipses. The moon is also one of the objects of human scientific research and space exploration, and at the same time, to a certain extent, it also provides a resource base for future space development.

Categories: Science & Engineering.

Analysis: From the following information, we can know that the moon is rounder than the earth, and we can know it from the flattening rate alone.

Earth: semi-major diameter 149,597,887 km 000 11 AU)

The circumference of the orbit is trillions of meters.

Astronomical unit) orbital eccentricity 710 22

Perihelion 147,098,074 km.

289 9 astronomical units).

Apohelion 152,097,701 km.

710 3 astronomical units).

The sidereal orbits 96 days.

019 1 Julian years).

Rendezvous period No data available.

The average orbital velocity is kilometers in seconds.

Maximum orbital speed in kilometers and seconds.

The minimum orbital speed is kilometers per second.

The orbital ecliptic is tilted 05°

with the Sun at the equator.

The ascending node longitude is 36°

The perihelion angle is 83°

Buried branch star 1 (Moon), see also asteroid 3753 physical properties Equatorial diameter 12, km.

Pole diameter 12, km.

The average diameter of the Earth is 12, km.

Flattening rate 35 equatorial circumference 40, km.

Pole circumference 39, km.

The surface area is 510,067,420 km².

Volume cubic kilometers.

Mass kg.

Density grams cubic centimeters.

Equatorial surface gravity meters per second squared [1].

32 gravitational constant).

Escape velocity in kilometers and seconds.

The sidereal rotation period is 258 days ( hours).

Rotation speed in kilometers = meters and seconds.

Moon: Average orbital radius of 384,400 km.

Orbital eccentricity.

Perigee distance 363,300 km.

Apogee distance 405,500 km.

The average revolution period is 27 days, 7 hours, 43 minutes and seconds.

The average rpm speed is in kilometers and seconds.

The orbital inclination varies between AND and .

The angle with the ecliptic amusement is .

Ascension node right ascension.

Pergee spokes.

Physical characteristics The diameter of the equator is 3, km.

The diameter of the poles is 3, km.

Flattened surface area square kilometers.

Flattening volume cubic kilometers.

Mass kg.

The average density is times that of water.

Equatorial gravitational acceleration m s2

Earth's 1 6

Escape velocity in kilometers and seconds.

Rotation period: 27 days, 7 hours, 43 minutes and seconds.

Synchronous rotation) rotation speed in meters and seconds (at the equator).

The axis of rotation inclination varies between and .

The angle to the ecliptic is.

Albedo at full moon apparent magnitude.

Surface temperature (t) -233 123 (average -23) atmospheric pressure kPa.

The universe has been mysterious since ancient times, and human beings have always been full of curiosity about it, but the shape of the earth and some other planets has only been discovered in modern times, and many of our planets are elliptical, similar to round, and some people wonder why the earth, the moon, and the sun are all round or quasi-round? Why are the earth, the moon, and the sun all round or quasi-circular? This is due to the gravitational pull, where there is a strong gravitational pull between the planets, forming a circular planet in an environment that pulls on each other.