What is the trajectory of the earth's revolution?
What is the trajectory of the earth's revolution? The earth is the home on which we live. Although humans are not the first creatures to survive on the earth, they are But our exploration of the earth has never stopped. So the following is about the trajectory of the earth's revolution. What is the orbit of the earth? 1
It is an elliptical orbit around the sun;
According to Kepler’s first law, the orbit of any planet is an ellipse, and the earth’s orbit is close to a perfect circle , the sun is at one focus of the ellipse;
The earth's revolution means that the earth rotates around the sun in an elliptical orbit; just like the earth's rotation has its own unique regularity, due to the gravitational field of the sun and the effect of the rotation, The revolution of the earth; the revolution of the earth has its own laws; the laws of the earth's revolution are predicted from the earth's orbit, the earth's orbital plane, the ecliptic angle, the period of the earth's revolution, the speed of the earth's revolution and the effects of the earth's revolution.
The yellow and red angle of the Earth's revolution
Every point of the Earth's orbit is on the same plane, and this plane is the Earth's orbital plane. The Earth's orbital plane appears as the ecliptic plane on the celestial sphere, which is on the same plane as the sun's annual apparent movement route.
The rotation and revolution of the earth proceed simultaneously. On the celestial sphere, the rotation is represented by the celestial axis and the celestial equator, and the revolution is represented by the yellow axis and the ecliptic. The celestial equator is on one plane, and the ecliptic is on another plane. The planes where these two concentric great circles lie form an angle of 23°26′. This angle is called the ecliptic angle.
The existence of the yellow-red angle actually means that when the earth revolves around the sun, the rotation axis is tilted to the earth's orbital plane. Since the Earth's axis is perpendicular to the celestial equatorial plane, the angle between the Earth's axis and the Earth's orbital plane should be 90° - 23°26', or 66°34'. No matter where the earth rotates, this tilt angle remains unchanged.
During the Earth's revolution, the spatial direction of the Earth's axis does not change significantly for a long period of time. The North Pole points to the Alpha star of the Ursa Minor constellation, that is, near the North Star. This is the position of the celestial North Pole. That is to say, the earth's axis moves parallel during the earth's revolution, so no matter where the earth revolves, the angle between the earth's axis and the earth's orbital plane remains unchanged, and the ecliptic angle remains unchanged.
The existence of the yellow-red angle also indicates the deviation of the Yellow Pole and the Celestial Pole, that is, the Yellow North Pole (or Yellow South Pole) and the Celestial North Pole (or Celestial South Pole) deviate by 23°26′ on the celestial sphere.
Most of the globes we have seen have a tilted axis of rotation, with an inclination angle of 66°34′ to the tabletop (representing the Earth’s orbital plane), while the equatorial plane of the globe is 23°26′ to the tabletop. ′, this is the intuitive reflection of the intersection angle of yellow and red. What is the trajectory of the earth's revolution 2
The direction of the earth's rotation and revolution
Both are from west to east
1. The earth's rotation is about its axis at the North Pole The direction observed from above is counterclockwise, while the direction observed from above Antarctica is clockwise, which is customarily called rotation from west to east. The rotation period is one day. The rotation angular speed is 15 degrees per hour, and the linear speed varies with latitude and altitude. For example, the equatorial sea level is 464 meters/second, the height increases or decreases by 100 meters, and the linear velocity increases or decreases by 26 meters; the two poles are zero.
2. In addition to rotating on its axis, the earth also revolves in a certain orbit The sun's revolution period is one sidereal year, which is about 365 days, 6 hours, 9 minutes and 10 seconds. The revolution direction is also from west to east, and the orbit is an ellipse with an oblateness of 1/60. The perihelion of the orbit is 147.1 million kilometers, and the aphelion is 147.1 million kilometers. 152.1 million kilometers, the average distance from the sun is 59 minutes per day, the average linear speed is 29.78 kilometers per second, and the surface speed is 1.92*1014 square kilometers per day. The first two have seasonal changes.
How many times does the earth rotate in one year?
If the earth is stationary relative to the sun, the earth will rotate exactly once in one day.
But since the earth orbits the sun at the same time, when our location is facing the sun again, the earth has already orbited the sun at an angle. Assuming that one revolution (i.e. one year) takes 365 days, then this angle is 0.9863° (360°/365).
Since the Earth’s rotation and revolution are in the same direction, the Earth’s own rotation angle actually exceeds 360° in one day.
Using the principle of "equal interior angles" of parallel lines, we can calculate that the exceeded angle is exactly 0.9863°, that is, one rotation per day is 0.9863°. In this way, the extra rotation is 0.9863° every day, and the cumulative extra rotation in 365 days a year is 0.9863°×365≈360°, which is exactly one week.
So the answer to the previous question is: There are 365 days in a year, and the earth rotates 366 times. Is it a bit surprising?
In fact, the Earth orbits the sun once more than 365 days, which is 365 days, 5 hours, 48 ??minutes and 46 seconds, so the Earth actually rotates 366.2422 times in a year.
Since the angle of the Earth's rotation in one day is almost the same as one revolution (no more than 1°), people usually call the Earth's rotation one day as one day, which has little impact on daily life.
In astronomy, in order to distinguish the two, a normal day is called a solar day, and one rotation of the Earth is called a sidereal day. The time of a sidereal day is 23 hours, 56 minutes and 4.09 seconds. . What is the trajectory of the earth's revolution 3
Revolution speed
Earth revolution (3) The earth's revolution is a periodic circular motion. Therefore, the earth's revolution speed includes angular velocity and linear velocity. Two aspects. If we use the sidereal year as the Earth's revolution period, then the average angular speed of the Earth's revolution is 360° per year, which means that the Earth rotates 360° after 365.2564 days, which is about 0.986° per day, or about 59′8″ per day. < /p>
The total length of the Earth’s orbit is 940,000,000 kilometers. Therefore, the average linear speed of the Earth’s revolution is 940 million kilometers per year. That is, after 365.2564 days, the Earth has rotated 940 million kilometers, or 29.8 kilometers per second. , about 30 kilometers per second (linear speed = 940,000,000KM/365 days = 940,000,000 seconds/(365x24x3600) seconds = 29.8 kilometers (approximately 30 kilometers/second).
According to Kepler’s planet The second law of motion [2] shows that the earth's revolution speed is related to the distance between the sun and the earth. The angular speed and linear speed of the earth's revolution change as the distance between the sun and the earth changes. Fast, the angular speed and linear speed exceed their average values, the angular speed is 1°1′11″/day, and the linear speed is 30.3 kilometers/second;
When the earth passes the aphelion, the revolution The speed is slow. The angular speed and linear speed are both lower than their average values. The angular speed is 57′11″/day and the linear speed is 29.3 kilometers/second. The earth passes through perihelion in early January and aphelion in early July every year. Therefore, From the beginning of January to the beginning of July of that year, the distance between the earth and the sun gradually increased, and the earth's revolution speed gradually slowed down; from the beginning of July to the beginning of January next year, the distance between the earth and the sun gradually decreased, and the earth's revolution speed gradually accelerated.
We know that the Earth’s revolution, the vernal equinox and the autumnal equinox are equal parts of the ecliptic. If the Earth’s revolution 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 autumnal equinox to the ecliptic. The time required for the vernal equinoxes is equal to half of the whole year. However, the earth's revolution speed is uneven, so the time to travel the same distance must be unequal.
From the vernal equinox through the summer solstice to the autumnal equinox, the earth's revolution speed is slow and takes more than 186 days, which is longer than half of the whole year. This is the summer half of the northern hemisphere and the winter half of the southern hemisphere. As the sun passes from the autumnal equinox to the winter solstice to the vernal equinox, The Earth's revolution speed is relatively fast, taking 179 days, which is less than half of a whole year. This is the winter half of the year in the Northern Hemisphere and the summer half of the Southern Hemisphere. It can be seen that the change in the Earth's revolution speed is the fundamental reason for the unequal length of the four seasons on the Earth. Reason.
First understand a few terms:
1. One light year: refers to the distance traveled by light in a vacuum in one year. Note that light-year is a unit of length.
2. Earth revolution: Our earth orbits the sun along an ellipse with a very small eccentricity at a speed of 29.79 kilometers per second. A lap of 100 million kilometers takes 365 days, 5 hours, 48 ??minutes and 46 seconds, which is about one year. (The average distance between the sun and the earth is 150 million kilometers)
3. The ratio of the distance traveled by light in one year to the circumference of the Earth’s revolution: Since 1 light year is the distance traveled by light in one year Distance, the circumference of the earth's revolution is the arc length that the earth travels in one year, and the time is one year. So the ratio of the distance is the ratio of the speed of light 300,000km/s to the speed of the earth’s revolution 29.79km/s: n=300,000/29.79=10,000 times.
4. The distance for the earth to revolve around the sun: The distance here is actually the circumference, the arc length of one revolution. We already know that the radius of the earth's orbit is 150 million kilometers, so it is easy to calculate the circumference. According to the formula s=2×314×150 million, it is about 940 million kilometers.
5. According to the ultimate theoretical formula of ellipses, the orbital circumference is approximately 939901691.151 kilometers (due to computer limitations, it can only be accurate to this for the time being)
The commonly referred to earth’s revolution is The sun is a two-dimensional plane of the reference system, and the earth travels through the total space and time of the universe for one year, which is about 11.7 billion kilometers. The trajectory is spiral. The spring equinox in 2011 and the spring equinox in 2012 do not intersect, but Distances are billions of kilometers.