The mysterious and magical world of astronomy since ancient times has attracted the attention of mankind. People raised their heads up to the starry sky, and asked eternal questions about why the stars change their position, why day and night comes, why a blizzard howls somewhere, and somewhere in the desert plus 50 …
The movement of the stars and calendars
Most planets in the solar system revolve around themselves. At the same time, they all make revolutions around the Sun. Some do it quickly and swiftly, others - slowly and solemnly. Planet Earth is no exception, it is constantly moving in outer space. Even in ancient times, people, knowing the causes and mechanism of this movement, noticed a certain general pattern and began to make calendars. Even then, mankind was interested in the question of what speed of the Earth revolves around the Sun.
The sun rises at sunrise
The movement of the Earth around its axis is Earth day. And the full passage of our planet in an ellipsoidal orbit around the luminary is a calendar year.
If you stand on the North Pole and draw an imaginary axis through the Earth to the South Pole, it turns out that our planet is moving from west to east. Remember, even in the "Word of Igor’s Regiment" it is said that "The sun rises at sunrise"? The East always meets the sun's rays before the West. That is why the new year in the Far East begins earlier than in Moscow.
At the same time, scientists decided that only two points on our planet are in a static position relative to circular motion. These are the North and South Poles.
Crazy speed
All other places on the planet are in perpetual motion. What is the speed of the earth around the sun? At the equator, it is the highest and reaches 1, 670 km per hour. Closer to the middle latitudes, for example, in Italy, the speed is already much lower - 1200 km per hour. And the closer to the poles, the smaller and smaller it is.
The period of revolution of the Earth around its axis is 24 hours. So say the scientists. We call it simpler - a day.
And at what speed does the earth revolve around the sun?
350 times faster than a race car
In addition to rotation around the axis, the Earth also makes an ellipsoidal motion around a star named the Sun. At what speed does the earth rotate around the sun? Scientists have long calculated this indicator using complex formulas and calculations. The speed of the Earth around the Sun is 107 thousand kilometers per hour.
It’s hard to even try to imagine these crazy, unreal numbers. For example, even the maximum speed of a racing car - 300 kilometers per hour - is 356 times less than the speed of the Earth in orbit.
It seems to us that this Sun rises and rises, that the Earth is motionless, and the luminary makes a circle in the sky. For a very long time, humanity thought just that, until scientists have proved: everything happens the other way around. Today, even a schoolchild knows what is happening in the world: planets smoothly and solemnly move around the Sun, and not the other way around. The Earth is circulating around the Sun, and not at all, as ancient people previously believed.
So, we found out that the speed of rotation of the earth around the axis and the Sun is 1670 km per hour (at the equator) and 107 thousand kilometers per hour, respectively. Wow, we are flying!
Sunny and starry year
A full circle, or rather, an ellipsoidal oval, the planet Earth passes around the Sun in 356 days 5 hours 48 minutes 46 seconds. These figures are called astronomers "astrological year." Therefore, to the question "What is the frequency of the Earth's revolution around the Sun?" we answer simply and succinctly: "Year." This indicator remains unchanged, but for some reason every four years we have a leap year in which there is one more day.
It’s just that astronomers agreed a long time ago that the extra 5 hours are not counted “kopecks” every year, but chose the number of the astronomical year that is a multiple of days. Thus, the year is 365 days. But in order to prevent a malfunction over time, so that the natural rhythms do not shift in time, every four years a single extra day appears in the calendar in February. These quarter-days for 4 years "gather" in a full day - and we celebrate a leap year. Thus, when answering the question of what is the frequency of the Earth's revolution around the Sun, feel free to say that it is one year.
In the scientific world there are the concepts of "sunny year" and "stellar (sidereal) year." The difference between them is about 20 minutes and it comes because our planet faster moves in orbit than the Sun returns to a place that astronomers have identified as the vernal equinox. We already know the speed of the Earth's revolution around the Sun, and the full period of the Earth's revolution around the Sun is 1 year.
Days and years on other planets
The nine planets of the solar system have their own “concepts” of speed, what such a day is and what an astronomical year is.
The planet Venus, for example, revolves around itself 243 Earth days. Can you imagine how much you can do in one day? And how long the night lasts!
But on Jupiter, the opposite is true. This planet is spinning around its axis with gigantic speed and manages to make a 360-degree revolution in 9.92 hours.
The speed of the Earth's passage in orbit around the Sun is a year (365 days), but Mercury is only 58.6 Earth days. Mars, the planet closest to Earth, lasts almost the same day as it does on Earth - 24 and a half hours, but the year is almost twice as long - 687 days.
The revolution of the earth around the sun is 365 days. Now, let's multiply that figure by 247.7 and get one year on the planet Pluto. We have passed the millennium, and on the farthest planet in the solar system - only four years.
These are paradoxical quantities and figures that are frightening in their scale.
Mysterious ellipse
To understand why the seasons periodically change on planet Earth, why it is hot in the middle lane and cold in the winter in our country, it’s important not only to answer the question of how fast the Earth rotates around the Sun, and which way. It is also necessary to understand how it does this.
And she does this not in a circle, but in an ellipse. If we draw the Earth’s orbit around the Sun, we will see that it is closest to the luminary in January, and farthest in July. The closest point in the Earth's position in orbit is called perihelion, and the farthest - aphelion.
Since the Earth’s axis is not in a strictly vertical position, but deviated by about 23.4 degrees, and with respect to the ellipsoid orbit, the angle of inclination increases to 66.3 degrees, it turns out that in different positions the Earth exposes the Sun to different sides.
Due to the inclination of the orbit, the Earth turns to the luminary in different hemispheres, hence the change of weather. When winter rages in the Northern Hemisphere, hot summer blooms in the Southern Hemisphere. Six months will pass - and the situation will change exactly the opposite.
Spin, earthly luminary!
Does the sun revolve around anything? Of course! There are no absolutely motionless objects in space. All planets, all their satellites, all comets and asteroids spin like clockwork. Of course, different celestial bodies have different rotation speeds, and the angle of inclination of the axis, but still they are always in motion. And the Sun, which is a star, is no exception.
The solar system is not an independent enclosed space. It enters a huge spiral galaxy called the Milky Way. It, in turn, includes no less than 200 billion stars. The sun moves in a circle relative to the center of this galaxy. The rotation of the Sun around the axis and the Milky Way galaxy, scientists also calculated using long-term observations and mathematical formulas.
Today there is such data. The Sun passes its full cycle of circular motion around the Milky Way in 226 million years. In astronomical science, this figure is called the "galactic year." Moreover, if we imagine the surface of the galaxy flat, then our luminary makes small oscillations up and down, turning alternately in the Northern and the Southern hemispheres of the Milky Way. The frequency of such fluctuations is 30-35 million years.
Scientists believe that the Sun during the existence of the Galaxy managed to make 30 full revolutions around the Milky Way. Thus, the Sun has only lived 30 galactic years. In any case, scientists say so.
Most scientists believe that life on Earth originated 252 million years ago. Thus, it can be argued that the first living organisms on Earth appeared when the Sun made its 29th revolution around the Milky Way, that is, on the 29th year of its galactic life.
The body and gases move at different speeds.
We learned a lot of interesting facts. We already know the indicator of the speed of the Earth's revolution around the Sun, we have found out what the astronomical and galactic year is, with what speed the Earth and the Sun move in their orbits, and now we will determine what speed the Sun rotates around its axis.
The fact that the sun rotates, was noticed by ancient researchers. Similar spots appeared and disappeared on it periodically, which made it possible to draw a conclusion about its rotation around the axis. But at what speed? Scientists, possessing the most modern research methods, argued about this for a very long time.
After all, our luminary has a very complex composition. His body is solid liquid. Inside is a solid core, around which there is a hot liquid mantle. Above it is a hard crust. In addition to all this, the surface of the Sun is shrouded in hot gas, which is constantly burning. It is a heavy gas that consists mainly of hydrogen.
So, the very body of the Sun rotates slowly, and this burning gas - quickly.
25 days and 22 years
The outer shell of the Sun makes a complete rotation around its axis in 27 and a half days. Astronomers were able to determine this by observing sunspots. But this is the average value. For example, sunspots on the equator rotate faster and make a revolution around the axis in 25 days. At the poles, spots move at a speed of 31 to 36 days.
The star’s body itself rotates around its axis in 22.14 years. In general, in a hundred years of earthly life, the Sun will turn around its axis only four and a half times.
Why do scientists so accurately study the rotation speed of our luminary?
Because it provides answers to many questions of evolution. After all, the star the Sun is the source of life of all life on Earth. It is because of outbreaks on the Sun, as many researchers believe, life appeared on Earth (252 million years ago). And precisely because of the behavior of the Sun in ancient times, dinosaurs and other reptiles died.
