The earth revolves around. Significant climate change is coming. How long does it take the earth to revolve around the sun
In the modern era, the Earth's axis of rotation is inclined to the plane of the orbit at an angle of 66.5°. It leads to change of seasons and inequality of day and night- the most important consequences of the Earth's orbit around the Sun.
If the earth's axis were perpendicular to the plane of the orbit, the day would always be equal to the night and the heating of the earth's surface during the year would decrease from the equator to the poles and there would be no change of seasons.
The inclination of the earth's axis to the plane of the orbit and the preservation of its orientation in space cause a different angle of incidence of the sun's rays and, accordingly, differences in the flow of heat to the earth's surface in different seasons of the year, as well as unequal lengths of day and night throughout the year at all latitudes, except for the equator, where day and night are always equal to 12 hours.
On the equinoxes of March 21 and September 23 at all latitudes, the duration of the day and night is 12 hours. The sun's rays fall vertically at the equator. On the day of the summer solstice on June 22, the rays fall vertically on the northern tropic, whose latitude is 23 0 27 ". Round the clock, not only the polar regions are illuminated, but also the space behind them up to latitude 66 ° 33" (Arctic Circle). In the southern hemisphere at this time, only that part of it that lies between the equator and the southern Arctic Circle (66 ° 33 ") turns out to be illuminated. Beyond it, on June 22, the earth's surface is not illuminated.
On the day of the winter solstice on December 22, everything happens the other way around. The sun's rays are already falling sheer on the southern tropic. Lighted in the southern hemisphere are areas that lie not only between the equator and the tropic, but also around the south pole. This situation continues until March 21, when the day of the spring equinox comes. The annual movement of the Earth around the Sun with a constant inclination of the axis of rotation leads to a regular change of seasons.
The belts of white summer nights and short winter days (58-66.5°N and S) exist for a short time. With the approach of the summer solstice, the time of white nights comes, and in winter - twilight days. The appearance of white nights is associated with the refraction of rays in earth's atmosphere, as a result of which the luminaries appear above their actual position above the horizon.
Geographic Consequences daily rotation Earth
Rotation of the Earth around its axis- Another important property that our planet has. When viewed from the north pole, the rotation of the Earth is counterclockwise, or, as is commonly believed, from west to east. The angle of rotation is the same at all latitudes. In one hour, each point on the surface of the Earth moves 15° from its original position. But at the same time, the linear speed is inversely proportional to the geographic latitude. At the equator it is 464 m/s, and at latitude 65° it is only 195 m/s. There are several geographic consequences associated with the axial rotation of the Earth. The first consequence relates to the contraction of the terrestrial spheroid. The second consequence is the change of day and night. The third, most significant, meaning of the Earth's rotation is the formation of a turning force, or Coriolis force (to the right in the northern hemisphere, to the left in the southern). At the equator, the Coriolis force is zero. Under the influence of the deflecting force of the Earth's rotation, the winds of temperate latitudes of both hemispheres take a predominantly westerly direction, and in tropical latitudes - east (trade winds). A similar manifestation of the Coriolis force is found in the direction of movement of ocean waters. However, sea currents under the influence of the Coriolis force are displaced from the direction of the prevailing winds at an angle of 30-35 ° to the right or left, depending on the hemisphere. The trade winds cause the flow to shift north and south of the equator. To compensate for the outflow, cold deep waters rise here. Therefore, the temperature of surface water at the equator is lower by 2-3°C than in neighboring tropical regions. The slow rise of deep waters into the upper layers of the ocean is called upwelling, and the sinking is called downwelling.
In addition to equatorial upwelling, the rise or fall of water occurs near the coastline of water bodies.
The Coriolis force can explain why the right banks of rivers in the northern hemisphere are steeper than the left, and vice versa in the southern hemisphere.
In everyday life, the average solar time is inconvenient to use, since it is different on each meridian, local time. Therefore, at the International Astronomical Congress in 1884, a zone account of time was adopted. Behind standard time the local time of the middle meridian of each belt is taken. The time of the zero (Greenwich) meridian is taken as universal time. The belts are counted to the east. In two neighboring zones, standard time differs by exactly 1 hour.
In our country, standard time was introduced on July 1, 1919. Russia is located in ten time zones: from the second to the eleventh. However, in order to more rational use in the summer of daylight in our country in 1930, by a special decree, the clocks were moved 1 hour ahead - daylight savings time was introduced.
Since 1981, for the period from April to October, summer time due to the transfer of time for another hour ahead compared to the maternity. Thus, in summer, the time in Moscow actually corresponds to the local time on the meridian of 60 ° E. e. The daylight saving time of the second time zone is called Moscow.
Approximately along the 180° meridian, in 1884 a international date line. This is a conditional line, on both sides of which hours and minutes coincide, and calendar dates differ by one day.
The period of smooth transition from daylight to night darkness and back is called suby the standards. They are based on an optical phenomenon observed in the atmosphere before sunrise and after sunset, when it is still under the horizon, but illuminates the sky, from which light is reflected. The duration of twilight depends on the time of year and the latitude of the place of observation; at the equator, twilight is short, increasing with latitude. There are three periods of twilight. Civil twilight observed when the center of the Sun sinks shallowly under the horizon (at an angle of up to 6 °) and for a short time. This is actually White Nights, when the evening dawn converges with the morning dawn. In summer they are observed at latitudes of 60° or more. Navigational twilight are observed when the center of the solar disk plunges below the horizon by 6-12 °. At the same time, the horizon line is visible, and from the ship it is possible to determine the angle of the stars above it. And finally, aster onomic twilight are observed when the center of the solar disk plunges below the horizon by 12-18°.
Our planet is in in constant motion, it revolves around the Sun and its own axis. The earth's axis is an imaginary line drawn from the North to the South Pole (they remain motionless during rotation) at an angle of 66 0 33 ꞌ with respect to the plane of the Earth. People cannot notice the moment of rotation, because all objects are moving in parallel, their speed is the same. It would look exactly the same as if we were sailing on a ship and did not notice the movement of objects and objects on it.
A full rotation around the axis is completed within one sidereal day, consisting of 23 hours 56 minutes and 4 seconds. During this interval, then one or the other side of the planet turns towards the Sun, receiving from it a different amount of heat and light. In addition, the rotation of the Earth around its axis affects its shape (flattened poles are the result of the planet's rotation around its axis) and the deviation when bodies move in a horizontal plane (rivers, currents and winds of the Southern Hemisphere deviate to the left, Northern - to the right).
Linear and angular speed of rotation
(Earth rotation)
The linear speed of the Earth's rotation around its axis is 465 m / s or 1674 km / h in the equator zone, as we move away from it, the speed gradually slows down, in the North and south poles it is equal to zero. For example, for citizens of the equatorial city of Quito (the capital of Ecuador in South America), the rotation speed is just 465 m / s, and for Muscovites living on the 55th parallel north of the equator - 260 m / s (almost half as much) .
Every year, the speed of rotation around the axis decreases by 4 milliseconds, which is associated with the influence of the Moon on the strength of sea and ocean ebb and flow. The pull of the Moon "pulls" the water in the opposite direction to the Earth's axial rotation, creating a slight frictional force that slows the rotation rate by 4 milliseconds. The rate of angular rotation remains the same everywhere, its value is 15 degrees per hour.
Why does day turn into night
(The change of night and day)
The time of a complete rotation of the Earth around its axis is one sidereal day (23 hours 56 minutes 4 seconds), during this time period the side illuminated by the Sun is first “in the power” of the day, the shadow side is at the mercy of the night, and then vice versa.
If the Earth rotated differently and one of its sides was constantly turned towards the Sun, then there would be heat(up to 100 degrees Celsius) and all the water would evaporate, on the other side - on the contrary, frosts raged and the water was under a thick layer of ice. Both the first and second conditions would be unacceptable for the development of life and the existence of the human species.
Why do the seasons change
(Change of seasons on earth)
Due to the fact that the axis is inclined with respect to the earth's surface at a certain angle, its sections are obtained in different time different amounts of heat and light, which causes the change of seasons. According to the astronomical parameters necessary to determine the season, some points in time are taken as reference points: for summer and winter, these are the Solstice Days (June 21 and December 22), for spring and autumn, the Equinoxes (March 20 and September 23). From September to March, the Northern Hemisphere is turned towards the Sun for less time and, accordingly, receives less heat and light, hello winter-winter, the Southern Hemisphere at this time receives a lot of heat and light, long live summer! 6 months pass and the Earth moves to the opposite point of its orbit and the Northern Hemisphere already receives more heat and light, the days become longer, the Sun rises higher - summer is coming.
If the Earth were located in relation to the Sun exclusively in vertical position, then the seasons would not exist at all, because all points on the half illuminated by the Sun would receive the same and uniform amount of heat and light.
The earth rotates around its axis from west to east, that is, counterclockwise, if you look at the earth from the North Star (from the North Pole). In this case, the angular velocity of rotation, i.e., the angle by which any point on the surface of the Earth rotates, is the same and amounts to 15 ° per hour. Linear speed depends on latitude: at the equator it is the highest - 464 m / s, and the geographical poles are fixed.
The main physical proof of the rotation of the Earth around its axis is the experiment with Foucault's swinging pendulum. After the French physicist J. Foucault carried out his famous experiment in the Paris Pantheon in 1851, the rotation of the Earth around its axis became an indisputable truth. Physical evidence of the Earth's axial rotation is also the measurement of the 1° meridian arc, which is 110.6 km near the equator and 111.7 km near the poles (Fig. 15). These measurements prove the compression of the Earth at the poles, and it is characteristic only of rotating bodies. And finally, the third proof is the deviation of falling bodies from the plumb line at all latitudes, except for the poles (Fig. 16). The reason for this deviation is due to their retention by inertia of a greater linear velocity of the point A(at height) compared to point IN(near the earth's surface). Falling objects are deflected on the Earth to the east because it rotates from west to east. The magnitude of the deviation is maximum at the equator. At the poles, bodies fall vertically, without deviating from the direction of the earth's axis.
The geographical significance of the axial rotation of the Earth is exceptionally great. First of all, it affects the figure of the Earth. The compression of the Earth at the poles is the result of its axial rotation. Previously, when the Earth rotated at a higher angular velocity, the polar contraction was more significant. Lengthening of the day and, as a result, a decrease in the equatorial radius and an increase in the polar one is accompanied by tectonic deformations earth's crust(faults, folds) and restructuring of the Earth's macrorelief.
An important consequence of the axial rotation of the Earth is the deflection of bodies moving in a horizontal plane (winds, rivers, sea currents, etc.). from their original direction: in the northern hemisphere - right, in the southern to the left(this is one of the forces of inertia, named Coriolis acceleration in honor of the French scientist who first explained this phenomenon). According to the law of inertia, each moving body strives to keep the direction and speed of its movement in the world space unchanged (Fig. 17). Deviation is the result of the fact that the body participates simultaneously in both translational and rotational movements. At the equator, where the meridians are parallel to each other, their direction in world space does not change during rotation and the deviation is zero. Towards the poles, the deviation increases and becomes greatest at the poles, since there each meridian changes its direction in space by 360 ° per day. The Coriolis force is calculated by the formula F = m x 2ω x υ x sin φ, where F is the Coriolis force, T is the mass of the moving body, ω is the angular velocity, υ is the speed of the moving body, φ is the geographic latitude. The manifestation of the Coriolis force in natural processes is very diverse. It is because of it that vortices of various scales arise in the atmosphere, including cyclones and anticyclones, winds and sea currents deviate from the gradient direction, influencing the climate and through it the natural zonality and regionality; the asymmetry of large river valleys is associated with it: in the northern hemisphere, many rivers (Dnepr, Volga, etc.) for this reason, the right banks are steep, the left ones are gentle, and vice versa in the southern hemisphere.
The rotation of the Earth is associated with a natural unit of time measurement - day and going on the change of night and day. Days are stellar and sunny. sidereal day is the time interval between two successive upper culminations of the star through the meridian of the observation point. During a sidereal day, the Earth makes a complete revolution around its axis. They are equal to 23 hours 56 minutes 4 seconds. Sidereal days are used in astronomical observations. true solar day- the time interval between two successive upper culminations of the center of the Sun through the meridian of the observation point. The duration of a true solar day varies throughout the year, primarily due to the uneven movement of the Earth in an elliptical orbit. Hence, they are also inconvenient for measuring time. For practical purposes, they use average solar days. Mean solar time is measured by the so-called mean Sun - an imaginary point that moves uniformly along the ecliptic and makes a complete revolution per year, like the true Sun. The average solar day is 24 hours. They are longer than stellar ones, since the Earth rotates around its axis in the same direction in which it orbits around the Sun with an angular velocity of about 1 ° per day. Because of this, the Sun moves against the background of the stars, and the Earth still needs to “turn around” by about 1 ° so that the Sun “comes” to the same meridian. Thus, in a solar day, the Earth rotates approximately 361 °. To convert true solar time to mean solar time, an amendment is introduced - the so-called time equation. Its maximum positive value+ 14 min on February 11, the largest negative -16 min on November 3. The beginning of the average solar day is taken as the moment of the lower climax of the average Sun - midnight. This time count is called civil time.
In everyday life, the average solar time is also inconvenient to use, since it is different on each meridian, local time. For example, on two neighboring meridians drawn at intervals of 1°, the local time differs by 4 minutes. The presence at various points lying on different meridians of their own local time led to many inconveniences. Therefore, at the International Astronomical Congress in 1884, a zone account of time was adopted. To do this, the entire surface the globe divided into 24 time zones, 15° each. Behind standard time the local time of the middle meridian of each belt is taken. To convert local time to zone time and vice versa, there is a formula T n – m = N – λ °, Where T P - standard time, m - local time, N- the number of hours equal to the number of the belt, λ ° is longitude expressed in hours. The zero (aka 24th) belt is the one in the middle of which the zero (Greenwich) meridian runs. His time is taken as universal time. Knowing universal time, it is easy to calculate standard time using the formula T n = T 0 + N, Where T 0 - universal time. The belts are counted to the east. In two neighboring zones, standard time differs by exactly 1 hour. For convenience, time zone boundaries on land are drawn not strictly along meridians, but along natural boundaries (rivers, mountains) or state and administrative borders.
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In our country, standard time was introduced on July 1, 1919. Russia is located in ten time zones: from the second to the eleventh. However, in order to make more rational use of daylight in summer in our country in 1930, a special government decree introduced the so-called maternity time, ahead of the standard time by 1 hour. So, for example, Moscow is formally located in the second time zone, where the standard time is calculated according to the local time of the meridian 30 ° E. But in fact, the time in winter in Moscow is set according to the time of the third time zone, corresponding to the local time on the meridian 45 ° E. e. Such a "relocation" operates throughout Russia, except for the Kaliningrad region, the time in which actually corresponds to the second time zone. |
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Rice. 17. Deviation of bodies moving along the meridian, in the northern hemisphere - to the right, in the southern hemisphere - to the left |
In a number of countries, the time is moved forward by one hour only for the summer. In Russia, since 1981, for the period from April to October, summer time due to the transfer of time for another hour ahead compared to the maternity. Thus, in summer, the time in Moscow actually corresponds to the local time on the meridian of 60 ° E. e. The time by which residents of Moscow and the second time zone in which it is located live is called Moscow. According to Moscow time in our country, trains and planes are scheduled, the time is marked on telegrams.
In the middle of the twelfth belt, approximately along the 180 ° meridian, in 1884 a international date line. This is a conditional line on the surface of the globe, on both sides of which hours and minutes coincide, and calendar dates differ by one day. For example, on New Year's Eve at 0000 hours, west of this line is already January 1 of the new year, and to the east - only December 31 of the old year. When crossing the border of dates from west to east in the count of calendar days, they return one day ago, and from east to west one day is skipped in the count of dates.
The change of day and night creates daily rhythm in living and inanimate nature. The daily rhythm is associated with light and temperature conditions. The daily course of temperature, day and night breezes, etc., are well known. The daily rhythm of living nature is very clearly manifested. It is known that photosynthesis is possible only during the day, in the presence of sunlight that many plants open their flowers at different hours. According to the time of manifestation of activity, animals can be divided into nocturnal and diurnal: most of them are awake during the day, but many (owls, bats, night butterflies) are in the darkness of the night. Human life also proceeds in a daily rhythm.
Rice. 18. Twilight and white nights
The period of smooth transition from daylight to night darkness and back is called twilight. IN they are based on an optical phenomenon observed in the atmosphere before sunrise and after sunset, when it is still (or already) under the horizon line, but illuminates the sky, from which light is reflected. The duration of twilight depends on the declination of the Sun (the angular distance of the Sun from the plane of the celestial equator) and the geographical latitude of the place of observation. At the equator, twilight is short, increasing with latitude. There are three periods of twilight. Civil twilight are observed when the center of the Sun plunges below the horizon shallowly (at an angle of up to 6 °) and for a short time. This is actually White Nights, when the evening dawn converges with the morning dawn. In summer they are observed at latitudes of 60° or more. For example / in St. Petersburg (latitude 59 ° 56 "N) they last from June 11 to July 2, in Arkhangelsk (64 ° 33" N) - from May 13 to July 30. Navigational twilight are observed when the center of the solar disk plunges below the horizon by 6–12°. At the same time, the horizon line is visible, and from the ship it is possible to determine the angle of the stars above it. And finally astronomical twilight are observed when the center of the solar disk submerges below the horizon by 12–18°. At the same time, the dawn in the sky still prevents astronomical observations of faint stars (Fig. 18).
The rotation of the Earth gives two fixed points - geographic poles(points of intersection of the imaginary axis of rotation of the Earth with the earth's surface) - and thus allows you to build a grid of parallels and meridians. Equator(lat. aequator - equalizer) - the line of intersection of the globe with a plane passing through the center of the Earth perpendicular to the axis of its rotation. Parallels(gr. parallelos - going side by side) - the lines of intersection of the earth's ellipsoid by planes parallel to the plane of the equator. meridians(lat. meridlanus - midday) - the lines of intersection of the earth's ellipsoid by planes passing through both of its poles. The length of the 1st meridian is on average 111.1 km.
For a very long time, people thought that our planet has a flattened shape and lies on 3 whales. A person is unable to notice its rotation, being on it itself. The reason for this is the size. They matter a lot! The size of a man is too small in relation to the size of the globe. Time moved forward, science progressed, and with it people's ideas about their own planet.
What have we come to today? Is it true that and not vice versa? What other astronomical knowledge in this area is valid? About everything in order.
Along its axis
Today we know that it takes part in two types of its movement simultaneously: the Earth revolves around the Sun and along its own imaginary axis. Yes, axles! Our planet has an imaginary line that "pierces" the surface of the earth at its two poles. Draw the axis mentally into the sky, and it will pass next to the North Star. That is why this point always seems to us motionless, and the sky seems to be rotating. We think that we are moving from east to west, but we note that it only seems to us! Such a movement is visible, since it is a reflection of the present rotation of the planet - along the axis.
The daily rotation lasts exactly 24 hours. In other words, in one day the globe performs one full circle along its own axis. Each of the earthly points first passes through the illuminated side, then the dark side. And a day later, everything repeats again.
For us, it looks like a constant change of days and nights: morning - afternoon - evening - morning ... If the planet did not rotate in this way, then there would be eternal day on the side facing the light, and eternal night on the opposite side. Horrible! It's good that it's not! In general, we figured out the daily rotation. Now let's find out how many times the Earth revolves around the Sun.
Solar "round dance"
This is also not visible to the naked eye. However, this phenomenon can be felt. We all know very well the warm and cold seasons. But what do they have in common with the movements of the planet? Yes, they have everything in common! The earth revolves around the sun in three hundred and sixty-five days, or one year. In addition, our globe is a participant in other movements. For example, together with the Sun and its "colleagues" - the planets, the Earth moves relative to its own galaxy - the Milky Way, which, in turn, moves relative to its "colleagues" - other galaxies.
It is important to know that in the whole Universe nothing is immovable, everything flows and changes! Note that the movement of the celestial body that we see is just a reflection of a rotating planet.
Is the theory correct?
Today, many people are trying to prove the opposite: they believe that it is not the Earth that revolves around the Sun, but, on the contrary, the celestial body around the globe. Some scientists talk about the joint movement of the Earth and the Sun, which occurs relative to each other. Perhaps someday the world's scientific minds will turn "upside down" all the scientific ideas about space known today! So, all the dots over the “and” are dotted, and you and I learned that around the Sun (at a speed, by the way, about 30 kilometers per second), and it makes a full revolution in 365 days (or 1 year), at the same time Our planet rotates its axis in a day (24 hours).
The mysterious and magical world of astronomy has attracted the attention of mankind since ancient times. People raised their heads up to the starry sky and asked eternal questions about why the stars change their position, why day and night come, why somewhere a blizzard howls, and somewhere in the desert plus 50 ...
The movement of the luminaries and calendars
Most of the 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, not knowing the causes and mechanism of this movement, noticed a certain general pattern and began to draw up calendars. Even then, mankind was interested in the question of what is the speed of the Earth's revolution around the Sun.
The sun rises at sunrise
The movement of the Earth around its axis is an Earth day. And the complete passage of our planet in an ellipsoidal orbit around the star 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 moves from west to east. Remember, even in the "Word of Igor's Campaign" it is said that "The sun rises at sunrise"? East always meets Sun rays before the west. That is why New Year on Far East comes earlier than in Moscow.
At the same time, scientists determined that only two points on our planet are in a static position relative to the North and South Poles.
crazy speed
All other places on the planet are in perpetual motion. What is the speed of the Earth's revolution around the Sun? At the equator, it is the highest and reaches 1670 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 rotation of the Earth around its axis is 24 hours. That's what scientists say. We call it easier - a day.
How fast does the earth revolve around the sun?
350 times faster than a racing car
In addition to rotating around its axis, the Earth also makes an ellipsoidal movement around a star called the Sun. With what speed Scientists have long ago 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 imagine these crazy, unrealistic numbers. For example, even the most racing car - 300 kilometers per hour - is 356 times less than the speed of the Earth in orbit.
It seems to us that it rises and rises, that the Earth is motionless, and the luminary makes a circle in the sky. Very for a long time humanity thought exactly that, until scientists proved: everything happens the other way around. Today, even a schoolboy knows what is happening in the world: the planets smoothly and solemnly move around the Sun, and not vice versa. The Earth revolves around the Sun, and not at all in the way that ancient people previously believed.
So, we found out that the speed of rotation of the earth around its axis and the Sun are respectively 1670 km per hour (at the equator) and 107 thousand kilometers per hour, respectively. Wow, we're flying!
solar and sidereal year
A full circle, or rather, an elliptical oval, the planet Earth goes around the Sun in 356 days 5 hours 48 minutes 46 seconds. Astronomers call these numbers the "astrological year". Therefore, to the question "What is the frequency of the Earth's revolution around the Sun?" we answer simply and concisely: "Year". This figure remains unchanged, but for some reason, once every four years we have a leap year, in which one day more.
It's just that astronomers have long agreed that the extra 5 and a half hours are not counted every year, but have chosen the number of the astronomical year, a multiple of days. Thus, the year is 365 days. But so that over time there is no failure, so that 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 are "gathered" into a full day - and we celebrate a leap year. Thus, answering the question of what is the frequency of the Earth's revolution around the Sun, feel free to say that one year.
In the scientific world there are concepts " solar year"and" stellar (sidereal) year. "The difference between them is about 20 minutes and it comes due to the fact that our planet orbits faster than the Sun returns to the place that astronomers have identified as the vernal equinox. We we already know the speed of revolution of the Earth around the Sun, and the total period of revolution of the Earth around the Sun is 1 year.
Days and years on other planets
The nine planets of the solar system have their own "concepts" about speed, about what a day is and what an astronomical year is.
The planet Venus, for example, revolves around itself for 243 Earth days. Can you imagine how much you can do there in one day? And how long is the night!
But on Jupiter, the opposite is true. This planet spins around its axis at a gigantic speed and manages to complete a 360-degree rotation in 9.92 hours.
The speed of the passage of the Earth in orbit around the Sun is a year (365 days), but Mercury is only 58.6 Earth days. On Mars, the planet closest to Earth, a day lasts almost as long as on Earth - 24 and a half hours, but a year is almost twice as long - 687 days.
The revolution of the Earth around the Sun is 365 days. Now let's multiply this figure by 247.7 and get one year on the planet Pluto. We have a millennium, and on the most distant planet in solar system— just four years.
Here are such paradoxical values and figures frightening in their scale.
Mysterious ellipse
To understand why the seasons change periodically on planet Earth, why we, in middle lane, and it is cold in winter, it is important not only to answer the question of how fast the Earth rotates around the Sun, and along which path. You also need to understand how she does it.
And she does this not in a circle, but in an ellipse. If we draw the orbit of the Earth around the Sun, then we will see that it is closest to the luminary in January, and farthest - in July. The closest point of the Earth's position in orbit is called perihelion, and the farthest point is called aphelion.
Since the earth's axis is not in a strictly vertical position, but is deviated by about 23.4 degrees, and with respect to the ellipsoidal orbit, the angle of inclination increases to 66.3 degrees, it turns out that in different provisions Earth exposes different sides to the Sun.
Due to the tilt of the orbit, the Earth turns to the star in different hemispheres, hence the change in weather. When winter rages in the Northern Hemisphere, hot summers bloom in the Southern Hemisphere. Six months later, the situation will change exactly the opposite.
Spin, earthly luminary!
Does the sun revolve around something? Of course! There are no absolutely motionless objects in space. All the planets, all their satellites, all comets and asteroids spin like clockwork. Of course, different celestial bodies and the speed of rotation is different, 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 closed space. It enters a huge spiral galaxy called the Milky Way. It, in turn, includes as many as 200 billion more stars. The sun moves in a circle around the center of this galaxy. The speed of rotation of the Sun around its axis and the Milky Way galaxy, scientists also calculated using long-term observations and mathematical formulas.
Today there is such data. Your full cycle of circular motion around milky way The sun travels in 226 million years. In astronomical science, this figure is called the "galactic year". Moreover, if we imagine the surface of the galaxy as flat, then our luminary makes small fluctuations up and down, ending up alternately in the Northern and 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 complete revolutions around the Milky Way. Thus, the Sun has lived only 30 galactic years so far. At least that's what scientists say.
Most scientists believe that life on Earth began 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, in the 29th year of its galactic life.
Body and gases move at different speeds
We learned a lot interesting facts. We already know the rate of rotation of the Earth around the Sun, we found out what the astronomical and galactic year is, how fast the Earth and the Sun move in their orbits, and now we will determine how fast the Sun rotates around the axis.
The fact that the Sun rotates was noticed by ancient researchers. Similar spots periodically appeared and disappeared on it, which made it possible to conclude that it rotates around its axis. But at what speed? Scientists, with the most modern methods studies have been arguing about this for a very long time.
After all, our luminary has a very complex composition. His body is solid. Inside is a solid core, around which is located a hot liquid mantle. Above it is hard bark. 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 body of the Sun itself 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 have been able to determine this by observing sunspots. But this is an average. For example, at the equator they rotate faster and make a revolution around the axis in 25 days. At the poles, sunspots move at a rate of 31 to 36 days.
The body of the star 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 study the speed of rotation of our star so accurately?
Because it gives answers to many questions of evolution. After all, the star Sun is the source of life for all life on Earth. It is because of the flares on the Sun, according to many researchers, life appeared on Earth (252 million years ago). And it was because of the behavior of the Sun that dinosaurs and other reptiles died in ancient times.
Shine brightly on us, Sun!
People are constantly wondering if the Sun will exhaust its energy, will it go out? Of course, it will go out - there is nothing eternal in the world. And for such massive stars there is a time of birth, activity and decay. But so far the Sun is in the middle of the evolutionary cycle and it has enough energy. By the way, at the very beginning this star was less bright. Astronomers have determined that at the most early stages development, the brightness of the Sun was 70 percent lower than it is now.
