How far is the sky from the earth 5, how far is the sky from the earth

It is about 6400 kilometers above the ground.

Earth's Atmosphere:

To put it simply, the air that surrounds the earth is called the atmosphere. The extent of the atmosphere is vast, stretching from the ground all the way to distant space.

Under the gravitational pull of the earth, a large amount of gas gathers around the earth, forming an atmosphere of thousands of kilometers. The density of the gas becomes thinner and thinner as the height above the ground increases. Sounding rockets still found a rarefied atmosphere at an altitude of 3,000 kilometres, and it is suggested that the upper limit of the atmosphere may extend to about 6,400 kilometres above the ground.

Scientists estimate that the mass of the atmosphere is about 6,000 trillion tons, almost one millionth of the total mass of the earth, including 78% nitrogen, 21% oxygen, argon, carbon dioxide neon, water vapor and dust.

According to the different characteristics of each layer of the atmosphere (such as temperature, composition and degree of ionization, etc.), it is divided into troposphere, stratosphere, mesosphere, thermosphere (ionosphere) and outer atmosphere from the ground.

The movement of air in the layer of the atmosphere close to the earth's surface is called the "troposphere" by convective movements dominated by updrafts and downdrafts. It varies in thickness, with a thickness of 8 kilometers above the Earth's poles and 17 kilometers above the equator, making it the densest layer in the atmosphere. Almost all the water vapor in the atmosphere is concentrated here, and it is a "big stage" to show the changes of the wind and clouds

Weather phenomena such as wind, rain, and snowfall all occur in the troposphere.

Above the troposphere, up to 50 kilometers above sea level, the air flow mainly moves horizontally and the convective phenomenon weakens, and this atmosphere is called the "stratosphere", also known as the "stratosphere". There is basically no moisture, it is clear and cloudless, and there are few weather changes, making it suitable for airplanes. At an altitude of 20 to 30 km, oxygen molecules, under the action of ultraviolet rays, form an ozone layer, which acts as a barrier to protect life on Earth from the attack of the sun's energetic particles.

Above the stratosphere, up to 85 kilometers above the Earth's surface, it is called the "mesosphere", also known as the "fugitive layer". Above the mesosphere, up to 500 kilometers above the Earth's surface, it is called the "thermosphere". Within these two layers, many interesting astronomical phenomena such as auroras, meteors, etc., often occur.

Human beings also use the thermosphere to achieve short-wave radio communication, so that people who are far away from the ocean can communicate with each other, because the atmosphere of the thermosphere is affected by solar radiation, the temperature is higher, the gas molecules or atoms are ionized in large quantities, and the recombination probability is less, forming an ionosphere, which can conduct electricity and reflect radio short waves.

Above the thermopause is the outer atmosphere, which extends to 1,000 kilometers above the Earth's surface. The temperature here is high, reaching thousands of degrees; The atmosphere is extremely thin, with a density of 1 billionth at sea level.

6400 km.

The range of human sight is infinite, that is, the sky as far as the eye can see can be infinite, but the distance of the object that can be seen clearly by a person is uncertain, it depends on the size of the object.

Theoretically, the human eye can image infinitely distant objects (in fact, any similar optical system can image infinitely distant objects), but people cannot see infinitely distant things, because the retina has limited resolving ability, that is, the resolution of the human eye is limited, so in this case, to see distant objects, you must have a large enough viewing angle, the human viewing angle range is determined by the pupil of the eye, so the human viewing angle range is also limited, so while the eyes are normal, The pupil also provides the greatest viewing angle, and the ability to see objects clearly depends on the size of the object. For example, astronomical telescopes have a large aperture, and the larger the aperture, the greater the range of viewing angles, and the farther away objects can be seen at a certain resolution.

Therefore, the distance at which the human eye can see objects is uncertain, and people can see the moon 400,000 kilometers away, but they cannot see the bacteria that are close at hand. Therefore, the farthest object that can be seen by the human eye depends on the size of the object. Here are some of the commonly used distances and what can be seen at these distances.

Strictly speaking, "sky" refers to the vast space around the earth, "sky" refers to space outside the earth's atmosphere, and "air" refers to the space of the earth's atmosphere. In short, the sky is the cosmic space other than the earth. Therefore, we cannot give exactly the area of the sky.

The surface area of the earth is about 51000000 square kilometers, which is what you call "the area of the earth".

The sky is infinite....The land area [Earth's land area] is about 148,939,100km 2.

If there is no atmosphere, people will not see the mesmerizing blue sky, but the dark and dreary cosmic space. Our blue sky is actually the atmosphere. As for asking how high the sky is, it is actually asking how thick the atmosphere is, or where is the upper limit of the atmosphere?

How high is the sky? In meteorology, the maximum altitude of 1,200 kilometers for the occurrence of aurora is often set as the upper limit of the atmosphere. Auroras are atmospheric phenomena that occur at altitudes of 70,1200 km.

It is believed that when a stream of energetic particles ejected from the sun enters the Earth's upper atmosphere from the poles, air molecules (atoms) are excited and ionized, and when the excited air molecules (atoms) are radiated back to the ground state, photons are emitted, and people see colorful and beautiful auroras. Above 1,200 kilometers, people can no longer see any atmospheric phenomena, and it is not the "sky" that people see.

It's about 18,000 kilometers!!

Upper atmosphereThe area above the Earth's atmosphere that begins to ionize (about 60 km). There is no consensus on the division of the initial altitude of the upper atmosphere, for example, some people refer to the lower limit of the upper atmosphere as the upper atmosphere when the sounding balloon can rise to an altitude of 30 km, while others refer to the area of the atmosphere above the middle top (about 80 km) as the upper atmosphere. The layered structure of the upper atmosphere is no longer obvious, and atmospheric particles with high thermal velocity may escape from the Earth's atmosphere by overcoming the constraints of the Earth's gravity, and gas particles from space may also enter the upper atmosphere.

Atmospheric stratification. The Earth's atmosphere can be divided into several layers according to its basic characteristics, but there are different stratification methods according to different characteristics. The common stratification methods are: according to the thermal state characteristics, it can be divided into troposphere, stratosphere, middle layer, thermosphere and outer layer (also known as exosphere or escape layer).

The upper limit of the troposphere is called the tropopause, with an altitude of about 17 18 km in the equatorial region and about 8 km in the polar regions. The atmosphere from the top of the troposphere to about 50 kilometers is called the stratosphere, and the atmosphere in the stratosphere mostly moves horizontally, and the convection is very weak, and the ozone layer is located in this area; The mesosphere, also known as the mesosphere, is an atmospheric area from the top of the stratosphere to about 80 km; The thermosphere is the atmosphere from the mesopause to 300,500 km; The atmosphere above the thermopause is called the outer atmosphere. According to the distribution characteristics of atmospheric composition with height, it can be divided into uniform layer and non-uniform layer. The homogeneous layer refers to the atmosphere from the ground to about 80 km, because the percentage of volume of the atmospheric components remains constant.

The average molecular weight of a homogeneous layer is gram mol, which is a constant. The heterogeneous layer is an atmospheric region of more than 80 km, and the volume percentage of different atmospheric components varies with altitude, and the average molecular weight is no longer constant. According to the ionization characteristics of the atmosphere, it can be divided into ionosphere and neutral sphere.

The neutral sphere, also known as the non-ionosphere, refers to the atmosphere dominated by neutral components. The ionosphere can be further divided into D, E, and F.

Below 80 km, the atmosphere is in a homogeneous state of mixture; Above about 80 km, the atmospheric turbulence gradually disappears and gradually transitions to a state of molecular diffusion equilibrium, reaching complete diffusion equilibrium above 120 km. Diffusion equilibrium is that under the action of the gravitational field, the heavy components of the atmosphere are distributed in the lower layers, and the light components are distributed in the upper layers, so that the average molar molecular weight of the atmosphere decreases with altitude. In addition to molecular motions in the upper atmosphere, there are macroscopic movements such as circulation, tides, and acoustic waves on a global scale.