Why is the sidereal year the true cycle of the Earth s revolution?

Whether in a sidereal year or a return year, the Earth revolves 360° around the Sun! This is the cycle of the four seasons. The reason why sidereal years differ in time from return years is because of the timer they employ.

Different. The return year is a calendar year in which the time is synchronized with the time of the earth's crust and the production of the sun, using a natural timer.

Natural timekeepers are affected by solid tides, and the rotation of the earth's crust is uneven, so the time of each return year is not equal.

The sidereal year uses an artificial timer and is not affected by solid tides, so the time is fixed over a longer period of time. If there is an error with the natural timer, it should be solved by leap seconds.

Just like a sidereal day, a sidereal day is the true rotation period of the Earth, and a sidereal day is equal to 23 hours, 56 minutes and 4 seconds. Not what we often call 24 hours.

The actual time interval required for the Earth to orbit the Sun, that is, the time it takes for the Sun to return to the same position when the Sun is observed to be observed from the Earth, is used only in astronomy. A sidereal year is equal to a mean solar day or 365 days, 6 hours, 9 minutes and 10 seconds[1] seconds. The Earth's orbital period is a sidereal year, and the sidereal year is the true cycle of the Earth's revolution, during a sidereal year, the center of the Earth starts from a point in the sky, circles the Sun, and then returns to that point; If viewed from Earth, the center of the Sun departs from a point on the ecliptic (a circle obtained by the Earth's orbital plane to cut off the celestial sphere), orbits the sky, and then returns to the same point (the same star).

During a sidereal year, it takes about 365 days, 6 hours, 9 minutes and 10 seconds for the Earth to orbit 360°. The difference between a sidereal year and a regressive year is that a sidereal year is a period of motion that uses a fixed point on the celestial sphere (such as a distant star) as a reference. The return year is the time interval between the solar center passing through the vernal equinox (or autumnal equinox, winter solstice or summer solstice) twice in a row on the ecliptic, that is, the time interval when the sun shines directly on the Tropic of Cancer (or Tropic of Capricorn) twice in a row.

Therefore, the return year is also known as the "solar year" and "seasonal year". The return year is slightly shorter than the sidereal year by about 20 minutes and 24 seconds.

Its period is about 365 days, 5:48:46. The length of day and night, the seasonal changes in the height of the sun at noon, the arrangement of the solar and lunar calendars, and the division of the 24 solar terms around the world are all based on the return year. The time difference between the sidereal year and the return year is named "precession" in the astronomical community.

Earth's orbital period: one year (days). The earth revolves around one revolution, which is roughly a "year".

365 days, 5 hours, 58 minutes, 56 seconds - solar year (return year), 365 days, 6 hours, 9 minutes, 10 seconds - sidereal year.

Answer: The Earth's orbital period is about 365 days, which is the time of one year.

The Earth orbits the Sun, and the year is 366 days. A normal year is 365 days.

The Earth's orbital cycle is 365 days, 6 hours, 9 minutes and 10 seconds, and every four years there will be one more day, and the extra day will be added to the last day of February, so every four years there is a leap year, three flat years.

The Earth's orbital cycle is one year. The time it takes for the earth to revolve is one year. There are two distinct cycles in the Earth's revolution, the return year and the sidereal year.

The return year refers to the time interval between the two consecutive passes of the sun through the vernal equinox, that is, the time elapsed by the sun's center from west to east along the ecliptic from the vernal equinox to the vernal equinox, also known as the solar year.

Information on the revolution of the Earth

The revolution of the earth is a periodic circular motion, therefore, the speed of the earth includes two aspects: angular velocity and linear velocity. If we use the sidereal year as the Earth's orbital period, then the average angular velocity of the Earth's revolution is 360 degrees per year, that is, after 365 points 2564 days, the Earth orbits 360 degrees, that is, about 0.986 degrees per day.

We know that the vernal equinox and the autumnal equinox are equally divided to the ecliptic, and if the earth's orbital speed is uniform, then the time it takes for the sun to travel from the vernal equinox to the autumnal equinox should be the same as the time it takes for the sun to travel from the vernal equinox to the vernal equinox, each of which is half of the whole year.

Apparent sun from the vernal equinox through the summer solstice to the autumn equinox, the earth's rotation speed is slower, it takes more than 186 days, longer than half of the year, this is the summer half of the northern hemisphere and the southern hemisphere of the winter half of the sun from the autumn equinox through the winter solstice to the vernal equinox, the earth's rotation speed is faster, it takes 179 days, shorter than half of the year, this is the winter half of the northern hemisphere and the summer half of the southern hemisphere.

The cycle of the Earth's revolution is one year, i.e. 365 days. Days, to be exact, so there is a leap year every four years.

First of all, the Earth's orbital period means that the Earth revolves around the Sun, and one revolution of the Earth is 365 days.

Earth is one of the eight planets in the solar system, the third in order of near and far from the sun, and it is also the terrestrial planet with the largest diameter, mass and density in the solar system, 100 million kilometers away from the sun. The Earth rotates from west to east while revolving around the Sun. Now 4.046 billion years old, it has a natural satellite, the Moon, and the two form a celestial system, the Earth-Moon System.

It originated from the primordial solar nebula 4.6 billion years ago.

The Earth's equatorial radius is kilometers, the polar radius is kilometers, the average radius is about 6371 kilometers, and the equatorial circumference is about 40076 kilometers. The surface area of the earth is 100 million square kilometers, of which 71% is oceans and 29% is land.

The Earth's interior has the Earth's core, mantle, and crustal structure, and the Earth's exterior has the hydrosphere, atmosphere, and magnetic field. The Earth is the only celestial body in the universe known to have life, and is home to millions of creatures, including humans.

The first stage is the formation of the Earth's sphere, which is roughly 46 million to 100 million years ago, when the Earth was born, which is very different from the 21st century. Scientists theorize that the Earth began as a red-hot ball of liquid material, mainly magma. Over time, the temperature of the earth's surface continues to drop, and a solid core gradually forms.

The dense material moves towards the center of the earth, and the less dense material (rocks, etc.) floats on the surface of the earth, which forms a earth whose surface is mainly composed of rocks.

The second stage is the Archean and Proterozoic periods. Its time limit is between 4200 and 543 MA. The earth is constantly releasing energy outward, and the water vapor, carbon dioxide and other gases released by the continuous eruption of hot magma constitute a very thin early atmosphere - the primitive atmosphere.

As the water vapor in the primeval atmosphere continues to increase, more and more water vapor condenses into small water droplets, which then converge into rainwater and fall to the surface. And just like that, the primordial ocean was formed.

The third stage is the Phanerozoic period, which lasts from 543 mA to the present. The duration of the Phanerozoic is relatively short, but during this period, the organisms and their flourishing, the geological evolution is very rapid, the geological processes are rich and colorful, and the geological bodies are all over the world, widely preserved, which can be observed and studied very well, and are the main research objects of geological science, and the basic theories and basic knowledge of geology have been established.

There are two cycles of the earth's rotation, one is based on the sun, called the solar day, and the time is 24 hours; A sidereal day is called a sidereal day, and the time is 23 minutes, 56 minutes, and 4 seconds. A sidereal day is the true cycle of the Earth's rotation.

There are two cycles of the earth's revolution, one is based on the sun, called the return year, and the time is 365 days, 5 hours, 48 minutes and 46 seconds;

A star-based reference, called a sidereal year, is 365 days, 6 hours, 9 minutes, and 10 seconds. A sidereal year is the true cycle of the Earth's revolution.

The revolution of the earth means that the earth revolves around the sun in a certain orbit (theearthrevolutionaroundsun).

Just as the rotation of the earth has its own unique regularity, the rotation of the earth is caused by the gravitational field of the sun as well as the action of rotation. The rotation of the earth also has its own laws.

The laws of the earth's revolution are from the earth's orbit, the earth's orbital plane, the yellow-red angle, the period of the earth's revolution, the speed of the earth's revolution and the effect of the earth's revolution.

The orbital period is the time it takes for a planet to revolve around a star or a satellite around a planet. The Earth's orbital period is a sidereal year with a duration of 365 days, 6 hours, 9 minutes and 10 seconds or days.

The Earth's rotation has two cycles, the sidereal day and the solar day, so is there only one cycle of the Earth's rotational motion in the return year? There are three cycles of the Earth's revolution around the Sun: sidereal years, perigee years, and return years.

1. Sidereal year: A distant star is used as a reference.

The duration of the Earth's orbit around the Sun 360 degrees, t = 365 25636 days, it is the Earth's revolution.

of the real cycle. The angular velocity of the Earth's revolution can only be accurately and realistically calculated using sidereal years.

and linear velocity. 2 Perippe year: The Earth's orbit around the Sun is an elliptical orbit that is approximately perfectly circular, with the Earth's center passing through the perihelion (or aphelion) in the orbit twice in succession.

The interval is the period of change in the speed of the Earth's revolution. This is the definition of the nearest year. Due to the forward shift of perihelion and aphelion (11 seconds eastward per year), its length is (as shown in the figure below) perigee years:

t=365 25964 days are longer than sidereal years, and perigee years are also the distance between the sun and the earth.

The cycle of change is the cycle in which the value of solar radiation energy received by the whole earth changes, not the real cycle of the earth's revolution.

3 The return year is the point of direct sunlight.

The period of regression motion, t = 365 2422 days It is 0 01416 days shorter than the sidereal year

The phenomenon of a return year slightly shorter than a sidereal year is called precession.

Precession is the rotation of the earth and the axis of the earth.

As a result of the combination of motions, this combination determines that the position of the earth is not a fixed point, but a moving point that constantly moves westward in the orbit of the earth, so that one revolution of the earth is not equal to one rotation of the latitude of the direct point of the sun. Although the return year is not the real cycle of the earth's revolution, it is the cycle of seasonal changes on the earth, which is of great significance to human beings, and the concept of "year" in our life usually refers to the return year, and the specific annual calendar in the solar calendar is arranged according to the return year, which has become the focus of our learning. It is recommended that you check the rotation of the Earth.

Entry. The above content is a copy of some of the content of this entry, and there is a lot more in this entry that is well worth reading.

The period of the Earth's revolution is: 365 days, 6 hours, 9 minutes, 10 seconds, which is the time it takes for the Earth to make a 360° revolution around the Sun, which is called a sidereal year.

There is a problem with the past cognition, which cannot explain the problem that the direction of the Earth's axis does not change when it revolves around the Sun, and under the action of the Sun's gravity, the direction of the Earth's axis should also change, so that the direct point of light will not change, so there will be no change in the four seasons. So a year is not a revolution cycle.

Answer A Question Analysis: The true period of the Earth's revolution is the sidereal year, which is 365 days, 6 hours, 9 minutes and 10 seconds.

Test Center: This question examines the cycle of the Earth's revolution.

Comments: The key to solving this problem is to grasp the cycle of the earth's revolution and distinguish between the rotation period and the revolution period.

The cycle of the Earth's revolution is (one year).