The Earth's natural satellite is the Moon, a non-luminous body that reflects sunlight.
The study of the Moon began in 1959, when the Soviet Luna 2 spacecraft first landed on the Moon, and the Luna 3 spacecraft first took pictures of the far side of the Moon from space.
In 1966, Luna 9 landed on the Moon and established a solid soil structure.
The first people to walk on the moon were Americans Neil Armstrong and Edwin Aldrin. This happened on July 21, 1969. Soviet scientists for further study of the Moon preferred to use automatic vehicles - lunar rovers.
General characteristics of the Moon
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Average radius of the Moon, km |
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The mass of the Moon is 1/81 the mass of the Earth. The position of the Moon in orbit corresponds to one or another phase (Fig. 1).
Rice. 1. Moon phases
Moon phases- various positions relative to the Sun - new moon, first quarter, full moon and last quarter. During a full moon, the illuminated disk of the Moon is visible, since the Sun and Moon are on opposite sides from the Earth. During the new moon, the Moon is on the side of the Sun, so the side of the Moon facing the Earth is not illuminated.
The Moon always faces the Earth with one side.
The line that separates the illuminated part of the Moon from the unlit part is called terminator.
In the first quarter, the Moon is visible at an angular distance of 90" from the Sun, and the sun's rays illuminate only the right half of the Moon facing us. In other phases, the Moon is visible to us in the form of a crescent. Therefore, in order to distinguish the growing Moon from the old one, we must remember: the old Moon resembles the letter “C”, and if the Moon is waxing, then you can mentally draw a vertical line in front of the Moon and you will get the letter “P”.
Due to the proximity of the Moon to the Earth and its large mass, they form the Earth-Moon system. The Moon and Earth rotate around their axes in the same direction. The plane of the Moon's orbit is inclined to the plane of the Earth's orbit at an angle of 5°9".
The intersection of the orbits of the Earth and the Moon is called nodes of the lunar orbit.
Sidereal(from Latin sideris - star) month is the period of rotation of the Earth around its axis and the same position of the Moon on the celestial sphere in relation to the stars. It is 27.3 Earth days.
Synodic(from the Greek synod - connection) a month is the period of complete change of lunar phases, i.e. the period of the Moon returning to its original position relative to the Moon and the Sun (for example, from new moon to new moon). It averages 29.5 Earth days. The synodic month is two days longer than the sidereal month, since the Earth and Moon rotate around their axes in the same direction.
The gravity on the Moon is 6 times less than the gravity on Earth.
The relief of the Earth's satellite is well studied. The visible dark areas on the surface of the Moon are called “seas” - these are vast waterless lowland plains (the largest is “Oksan Bur”), and the light areas are called “continents” - these are mountainous, elevated areas. The main planetary structures of the lunar surface are ring craters with a diameter of up to 20-30 km and multi-ring circuses with a diameter of 200 to 1000 km.
The origin of ring structures is different: meteorite, volcanic and shock-explosive. In addition, there are cracks, shifts, domes and fault systems on the surface of the Moon.
Studies by the Luna-16, Luna-20, and Luna-24 spacecraft have shown that the surface clastic rocks of the Moon are similar to terrestrial igneous rocks - basalts.
The meaning of the Moon in the life of the Earth
Although the mass of the Moon is 27 million times less than the mass of the Sun, it is 374 times closer to the Earth and has a strong influence on the planet, causing rising tides in some places and low tides in others. This happens every 12 hours 25 minutes, since the Moon makes a full revolution around the Earth in 24 hours 50 minutes.
Due to the gravitational influence of the Moon and the Sun on the Earth, ebb and flow(Fig. 2).
Rice. 2. Scheme of the occurrence of ebbs and flows on Earth
The most distinct and important in their consequences are tidal phenomena in the wave shell. They represent periodic rises and falls in the level of oceans and seas, caused by the gravitational forces of the Moon and the Sun (2.2 times less than the lunar one).
In the atmosphere, tidal phenomena manifest themselves in semidiurnal changes in atmospheric pressure, and in the earth's crust - in the deformation of the solid matter of the Earth.
On Earth, there are 2 high tides at the point closest and farthest from the Moon and 2 low tides at points located at an angular distance of 90° from the Moon-Earth line. Highlight cygisian tides, which occur on new and full moons and quadrature- in the first and last quarter.
In the open ocean, tidal movements are small. Water level fluctuations reach 0.5-1 m. In the inland seas (Black, Baltic, etc.) they are almost not felt. However, depending on the geographic latitude and the contours of the coastline of the continents (especially in narrow bays), water during high tides can rise up to 18 m (Bay of Fundy in the Atlantic Ocean off the coast of North America), 13 m on the western coast of the Sea of Okhotsk. In this case, tidal currents are formed.
The main significance of tidal waves is that, moving from east to west following the apparent movement of the Moon, they slow down the axial rotation of the Earth and lengthen the day, change the figure of the Earth by reducing polar compression, cause pulsation of the Earth’s shells, vertical displacements of the earth’s surface, semidiurnal changes in atmospheric pressure change the conditions of organic life in the coastal parts of the World Ocean and, finally, affect the economic activities of coastal countries. Sea vessels can only enter a number of ports at high tide.
After a certain period of time on Earth they repeat solar and lunar eclipses. They can be seen when the Sun, Earth and Moon are on the same line.
Eclipse- an astronomical situation in which one celestial body blocks the light from another celestial body.
A solar eclipse occurs when the Moon comes between the observer and the Sun and blocks it. Since the Moon before an eclipse faces us with its unlit side, there is always a new moon before an eclipse, i.e. the Moon is not visible. It seems that the Sun is covered by a black disk; an observer from Earth sees this phenomenon as a solar eclipse (Fig. 3).
Rice. 3. Solar eclipse (the relative sizes of the bodies and the distances between them are relative)
A lunar eclipse occurs when the Moon, while aligned with the Sun and Earth, falls into the cone-shaped shadow cast by the Earth. The diameter of the Earth's shadow spot is equal to the minimum distance of the Moon from the Earth - 363,000 km, which is about 2.5 times the diameter of the Moon, so the Moon can be completely obscured (see Fig. 3).
Lunar rhythms are repeated changes in the intensity and nature of biological processes. There are lunar-monthly (29.4 days) and lunar-diurnal (24.8 hours) rhythms. Many animals and plants reproduce at a certain phase of the lunar cycle. Lunar rhythms are characteristic of many marine animals and plants of the coastal zone. Thus, people have noticed changes in their well-being depending on the phases of the lunar cycle.
Moon- the only celestial body that orbits the Earth, not counting the artificial Earth satellites created by man in recent years.
The moon continuously moves across the starry sky and, in relation to any star, per day moves towards the daily rotation of the sky by approximately 13°, and after 27.1/3 days it returns to the same stars, having described a full circle in the celestial sphere. Therefore, the period of time during which the Moon makes a complete revolution around the Earth in relation to the stars is called sidereal (or sidereal)) month; it is 27.1/3 days. The Moon moves around the Earth in an elliptical orbit, so the distance from the Earth to the Moon changes by almost 50 thousand km. The average distance from the Earth to the Moon is taken to be 384,386 km (rounded - 400,000 km). This is ten times the length of the Earth's equator.
Moon It itself does not emit light, so only its surface, the daylight side, illuminated by the Sun, is visible in the sky. Night time, dark, not visible. Moving across the sky from west to east, in 1 hour the Moon shifts against the background of stars by about half a degree, i.e., by an amount close to its apparent size, and in 24 hours - by 13º. FOR a month, the Moon in the sky catches up and overtakes the Sun, and the lunar phases change: new moon , first quarter , full moon And last quarter .
IN new moon The moon cannot be seen even with a telescope. It is located in the same direction as the Sun (only above or below it), and is turned towards the Earth by the night hemisphere. Two days later, when the Moon moves away from the Sun, a narrow crescent can be seen a few minutes before its sunset in the western sky against the background of the evening dawn. The first appearance of the lunar crescent after the new moon was called “neomenia” (“new moon”) by the Greeks. From this moment the lunar month begins.
7 days 10 hours after the new moon, a phase called first quarter. During this time, the Moon moved away from the Sun by 90º. From Earth, only the right half of the lunar disk, illuminated by the Sun, is visible. After sunset Moon is in the southern sky and sets around midnight. Continuing to move from the Sun more and more to the left. Moon in the evening it appears already on the eastern side of the sky. She comes in after midnight, every day later and later.
When Moon appears in the direction opposite to the Sun (at an angular distance of 180 from it), comes full moon. 14 days and 18 hours have passed since the new moon. After that Moon begins to approach the Sun from the right.
There is a decrease in illumination of the right part of the lunar disk. The angular distance between it and the Sun decreases from 180 to 90º. Again, only half of the lunar disk is visible, but its left part. 22 days 3 hours have passed since the new moon. last quarter. The moon rises around midnight and shines throughout the second half of the night, ending up in the southern sky by sunrise.
The width of the lunar crescent continues to decrease, and Moon gradually approaches the Sun from the right (western) side. Appearing in the eastern sky, every day later, the lunar crescent becomes very narrow, but its horns are turned to the right and look like the letter “C”.
They say, Moon old An ashen light is visible on the night part of the disk. The angular distance between the Moon and the Sun decreases to 0º. Finally, Moon catches up with the Sun and becomes invisible again. The next new moon is coming. The lunar month has ended. 29 days 12 hours 44 minutes 2.8 seconds passed, or almost 29.53 days. This period is called synodic month (from the Greek sy "nodos-connection, rapprochement).
The synodic period is associated with the visible position of the celestial body relative to the Sun in the sky. Lunar a synodic month is the period of time between successive phases of the same name Moons.
Your path in the sky relative to the stars Moon completes 7 hours 43 minutes 11.5 seconds in 27 days (rounded - 27.32 days). This period is called sidereal (from Latin sideris - star), or sidereal month .
No. 7 Eclipse of the Moon and the Sun, their analysis.
Solar and lunar eclipses are an interesting natural phenomenon, familiar to man since ancient times. They occur relatively often, but are not visible from all areas of the earth’s surface and therefore seem rare to many.
A solar eclipse occurs when our natural satellite - the Moon - in its movement passes against the background of the Sun's disk. This always happens at the time of the new moon. The Moon is located closer to the Earth than the Sun, almost 400 times, and at the same time its diameter is also approximately 400 times smaller than the diameter of the Sun. Therefore, the apparent sizes of the Earth and the Sun are almost the same, and the Moon can cover the Sun. But not every new moon there is a solar eclipse. Due to the tilt of the Moon's orbit relative to Earth's orbit, the Moon usually "misses" slightly and passes above or below the Sun at the time of the new moon. However, at least 2 times a year (but no more than five) the shadow of the Moon falls on the Earth and a solar eclipse occurs.
The lunar shadow and penumbra fall on the Earth in the form of oval spots, which travel at a speed of 1 km. per second run across the earth's surface from west to east. In areas that are in the lunar shadow, a total solar eclipse is visible, that is, the Sun is completely obscured by the Moon. In areas covered by penumbra, a partial solar eclipse occurs, that is, the Moon covers only part of the solar disk. Beyond the penumbra, no eclipse occurs at all.
The longest duration of the total eclipse phase does not exceed 7 minutes. 31 sec. But most often it is two to three minutes.
A solar eclipse starts from the right edge of the Sun. When the Moon completely covers the Sun, twilight sets in, as in dark twilight, and the brightest stars and planets appear in the darkened sky, and around the Sun you can see a beautiful radiant glow of pearl color - the solar corona, which is the outer layers of the solar atmosphere, not visible outside the eclipse. for their low brightness compared to the brightness of the daytime sky. The appearance of the corona changes from year to year depending on solar activity. A pink glow ring flashes above the entire horizon - this is the area covered by the lunar shadow, where sunlight penetrates from neighboring zones where a total eclipse does not occur, but only a partial eclipse is observed.
SOLAR AND LUNAR ECLIPSE
The Sun, Moon and Earth in the new moon and full moon stages rarely lie on the same line, because The lunar orbit does not lie exactly in the plane of the ecliptic, but at an inclination of 5 degrees to it.
Solar eclipses new moon. The Moon blocks the Sun from us.
Lunar eclipses. The Sun, Moon and Earth lie on the same line in the stage full moon. The Earth blocks the Moon from the Sun. The moon turns brick red.
Every year there are on average 4 solar and lunar eclipses. They always accompany each other. For example, if the new moon coincides with a solar eclipse, then the lunar eclipse occurs two weeks later, in the full moon phase.
Astronomically, solar eclipses occur when the Moon, as it moves around the Sun, completely or partially obscures the Sun. The apparent diameters of the Sun and the Moon are almost the same, so the Moon completely obscures the Sun. But this is visible from the Earth in the full phase band. A partial solar eclipse is observed on both sides of the total phase band.
The width of the band of the total phase of a solar eclipse and its duration depend on the mutual distances of the Sun, Earth and Moon. As a result of changes in distances, the apparent angular diameter of the Moon also changes. When it is slightly larger than the solar eclipse, a total eclipse can last up to 7.5 minutes; when it is equal, then one instant; if it is smaller, then the Moon does not completely cover the Sun. In the latter case, an annular eclipse occurs: a narrow bright solar ring is visible around the dark lunar disk.
During a total solar eclipse, the Sun appears as a black disk surrounded by a radiance (corona). Daylight is so weak that you can sometimes see stars in the sky.
A total lunar eclipse occurs when the Moon enters the Earth's shadow.
A total lunar eclipse can last 1.5-2 hours. It can be observed from all over the night hemisphere of the Earth, where the Moon was above the horizon at the time of the eclipse. Therefore, in this area, total lunar eclipses can be observed much more often than solar eclipses.
During a total lunar eclipse of the Moon, the lunar disk remains visible, but takes on a dark red hue.
A solar eclipse occurs on a new moon, and a lunar eclipse occurs on a full moon. Most often there are two lunar and two solar eclipses in a year. The maximum possible number of eclipses is seven. After a certain period of time, lunar and solar eclipses are repeated in the same order. This interval was called saros, which translated from Egyptian means repetition. Saros is approximately 18 years, 11 days. During each Saros there are 70 eclipses, of which 42 are solar and 28 are lunar. Total solar eclipses from a certain area are observed less frequently than lunar eclipses, once every 200-300 years.
CONDITIONS FOR A SUN ECLIPSE
During a solar eclipse, the Moon passes between us and the Sun and hides it from us. Let us consider in more detail the conditions under which a solar eclipse can occur.
Our planet Earth, rotating around its axis during the day, simultaneously moves around the Sun and makes a full revolution in a year. The Earth has a satellite - the Moon. The Moon moves around the Earth and completes a full revolution in 29 1/2 days.
The relative position of these three celestial bodies changes all the time. During its movement around the Earth, the Moon at certain periods of time finds itself between the Earth and the Sun. But the Moon is a dark, opaque solid ball. Finding itself between the Earth and the Sun, it, like a huge curtain, covers the Sun. At this time, the side of the Moon that faces the Earth turns out to be dark and unlit. Therefore, a solar eclipse can only occur during a new moon. During a full moon, the Moon passes away from the Earth in the direction opposite to the Sun and may fall into the shadow cast by the globe. Then we will observe a lunar eclipse.
The average distance from the Earth to the Sun is 149.5 million km, and the average distance from the Earth to the Moon is 384 thousand km.
The closer an object is, the larger it seems to us. The Moon, compared to the Sun, is almost 400 times closer to us, and at the same time its diameter is also approximately 400 times less than the diameter of the Sun. Therefore, the apparent sizes of the Moon and the Sun are almost the same. The Moon can thus block the Sun from us.
However, the distances of the Sun and Moon from the Earth do not remain constant, but change slightly. This happens because the path of the Earth around the Sun and the path of the Moon around the Earth are not circles, but ellipses. As the distances between these bodies change, their apparent sizes also change.
If at the moment of a solar eclipse the Moon is at its smallest distance from the Earth, then the lunar disk will be slightly larger than the solar one. The Moon will completely cover the Sun, and the eclipse will be total. If during an eclipse the Moon is at its greatest distance from the Earth, then it will have a slightly smaller apparent size and will not be able to cover the Sun entirely. The light rim of the Sun will remain uncovered, which during an eclipse will be visible as a bright thin ring around the black disk of the Moon. This type of eclipse is called an annular eclipse.
It would seem that solar eclipses should occur monthly, every new moon. However, this does not happen. If the Earth and the Moon moved in a visible plane, then at every new moon the Moon would actually be exactly in a straight line connecting the Earth and the Sun, and an eclipse would occur. In fact, the Earth moves around the Sun in one plane, and the Moon around the Earth in another. These planes do not coincide. Therefore, often during new moons the Moon comes either higher than the Sun or lower.
The apparent path of the Moon in the sky does not coincide with the path along which the Sun moves. These paths intersect at two opposite points, which are called the nodes of the lunar orbit. Near these points, the paths of the Sun and Moon come close to each other. And only when the new moon occurs near a node is it accompanied by an eclipse.
The eclipse will be total or annular if the Sun and Moon are almost at a node at the new moon. If the Sun at the moment of the new moon is at some distance from the node, then the centers of the lunar and solar disks will not coincide and the Moon will only partially cover the Sun. Such an eclipse is called a partial eclipse.
The moon moves among the stars from west to east. Therefore, the covering of the Sun by the Moon begins from its western, i.e., right, edge. The degree of closure is called the eclipse phase by astronomers.
Around the spot of the lunar shadow there is a penumbral region, here a partial eclipse occurs. The diameter of the penumbra region is about 6-7 thousand km. For an observer located near the edge of this region, only a small fraction of the solar disk will be covered by the Moon. Such an eclipse may go unnoticed altogether.
Is it possible to accurately predict the occurrence of an eclipse? Scientists in ancient times established that after 6585 days and 8 hours, which is 18 years 11 days 8 hours, eclipses are repeated. This happens because it is after such a period of time that the location in space of the Moon, Earth and Sun is repeated. This interval was called saros, which means repetition.
During one Saros there are on average 43 solar eclipses, of which 15 are partial, 15 are annular and 13 are total. By adding 18 years, 11 days and 8 hours to the dates of eclipses observed during one saros, we can predict the occurrence of eclipses in the future.
In the same place on Earth, a total solar eclipse is observed once every 250 - 300 years.
Astronomers have calculated the visibility conditions for solar eclipses many years in advance.
LUNAR ECLIPSE
Lunar eclipses are also among the “extraordinary” celestial phenomena. This is how they happen. The full light circle of the Moon begins to darken at its left edge, a round brown shadow appears on the lunar disk, it moves further and further and after about an hour covers the entire Moon. The moon fades and turns red-brown.
The diameter of the Earth is almost 4 times larger than the diameter of the Moon, and the shadow from the Earth, even at the distance of the Moon from the Earth, is more than 2 1/2 times the size of the Moon. Therefore, the Moon can be completely immersed in the Earth's shadow. A total lunar eclipse is much longer than a solar eclipse: it can last 1 hour and 40 minutes.
For the same reason that solar eclipses do not occur every new moon, lunar eclipses do not occur every full moon. The largest number of lunar eclipses in a year is 3, but there are years without any eclipses at all; This was the case, for example, in 1951.
Lunar eclipses recur after the same period of time as solar eclipses. During this interval, in 18 years 11 days 8 hours (saros), there are 28 lunar eclipses, of which 15 are partial and 13 are total. As you can see, the number of lunar eclipses in Saros is significantly less than solar eclipses, and yet lunar eclipses can be observed more often than solar ones. This is explained by the fact that the Moon, plunging into the shadow of the Earth, ceases to be visible on the entire half of the Earth not illuminated by the Sun. This means that each lunar eclipse is visible over a much larger area than any solar eclipse.
The eclipsed Moon does not disappear completely, like the Sun during a solar eclipse, but is faintly visible. This happens because some of the sun's rays come through the earth's atmosphere, are refracted in it, enter the earth's shadow and hit the moon. Since the red rays of the spectrum are least scattered and weakened in the atmosphere. During an eclipse, the moon takes on a copper-red or brown hue.
CONCLUSION
It is difficult to imagine that solar eclipses occur so often: after all, each of us has to observe eclipses extremely rarely. This is explained by the fact that during a solar eclipse the shadow from the Moon does not fall on the entire Earth. The fallen shadow has the shape of an almost circular spot, the diameter of which can reach at most 270 km. This spot will cover only a negligible fraction of the earth's surface. At the moment, only this part of the Earth will see a total solar eclipse.
The moon moves in its orbit at a speed of about 1 km/sec, i.e. faster than a gun bullet. Consequently, its shadow moves at high speed along the earth's surface and cannot cover any one place on the globe for a long time. Therefore, a total solar eclipse can never last more than 8 minutes.
Thus, the lunar shadow, moving across the Earth, describes a narrow but long strip, in which a total solar eclipse is successively observed. The length of the total solar eclipse reaches several thousand kilometers. And yet the area covered by the shadow turns out to be insignificant compared to the entire surface of the Earth. In addition, oceans, deserts and sparsely populated areas of the Earth are often in the zone of total eclipse.
The sequence of eclipses repeats itself almost exactly in the same order over a period of time called a saros (saros is the Egyptian word meaning “repetition”). Saros, known in ancient times, is 18 years and 11.3 days. Indeed, eclipses will be repeated in the same order (after any initial eclipse) after as much time as is necessary for the same phase of the Moon to occur at the same distance of the Moon from the node of its orbit as during the initial eclipse.
During each Saros there are 70 eclipses, of which 41 are solar and 29 are lunar. Thus, solar eclipses occur more often than lunar eclipses, but at a given point on the Earth’s surface, lunar eclipses can be observed more often, since they are visible over the entire hemisphere of the Earth, while solar eclipses are visible only in a relatively narrow band. It is especially rare to see total solar eclipses, although there are about 10 of them during each Saros.
No. 8 The Earth is like a ball, an ellipsoid of revolution, a 3-axis ellipsoid, a geoid.
Assumptions about the spherical shape of the earth appeared in the 6th century BC, and from the 4th century BC some of the evidence known to us was expressed that the Earth is spherical in shape (Pythagoras, Eratosthenes). Ancient scientists proved the sphericity of the Earth based on the following phenomena:
- circular view of the horizon in open spaces, plains, seas, etc.;
- the circular shadow of the Earth on the surface of the Moon during lunar eclipses;
- change in the height of stars when moving from north (N) to south (S) and back, due to the convexity of the noon line, etc. In his essay “On the Heavens,” Aristotle (384 – 322 BC) indicated that The earth is not only spherical in shape, but also has finite dimensions; Archimedes (287 - 212 BC) proved that the surface of water in a calm state is a spherical surface. They also introduced the concept of the Earth's spheroid as a geometric figure close in shape to a ball.
The modern theory of studying the figure of the Earth originates from Newton (1643 - 1727), who discovered the law of universal gravitation and applied it to study the figure of the Earth.
By the end of the 80s of the 17th century, the laws of planetary motion around the Sun were known, the very precise dimensions of the globe determined by Picard from degree measurements (1670), the fact that the acceleration of gravity on the Earth's surface decreases from north (N) to south (S ), Galileo's laws of mechanics and Huygens' research on the motion of bodies along a curvilinear trajectory. A generalization of these phenomena and facts led scientists to a well-founded view about the spheroidality of the Earth, i.e. its deformation in the direction of the poles (flatness).
Newton's famous work, “Mathematical Principles of Natural Philosophy” (1867), sets out a new doctrine about the figure of the Earth. Newton came to the conclusion that the figure of the Earth should be shaped like an ellipsoid of rotation with slight polar compression (this fact was justified by him by decreasing the length of the second pendulum with decreasing latitude and decreasing gravity from pole to equator due to the fact that “Earth slightly higher at the equator").
Based on the hypothesis that the Earth consists of a homogeneous mass of density, Newton theoretically determined the polar compression of the Earth (α) in a first approximation to be approximately 1: 230. In fact, the Earth is heterogeneous: the crust has a density of 2.6 g/cm3, while The average density of the Earth is 5.52 g/cm3. The uneven distribution of the Earth's masses produces extensive gentle convexities and concavities, which combine to form hills, depressions, depressions and other shapes. Note that individual elevations above the Earth reach heights of more than 8000 meters above the ocean surface. It is known that the surface of the World Ocean (MO) occupies 71%, land – 29%; the average depth of the World Ocean is 3800 m, and the average height of land is 875 m. The total area of the earth's surface is 510 x 106 km2. From the given data it follows that most of the Earth is covered with water, which gives grounds to accept it as a level surface (LS) and, ultimately, as the general figure of the Earth. The figure of the Earth can be represented by imagining a surface at each point of which the force of gravity is directed normal to it (along a plumb line).
The complex figure of the Earth, limited by a level surface, which is the beginning of the report of heights, is usually called a geoid. Otherwise, the surface of the geoid, as an equipotential surface, is fixed by the surface of oceans and seas that are in a calm state. Under continents, the geoid surface is defined as the surface perpendicular to the field lines (Figure 3-1).
P.S. The name of the Earth's figure - geoid - was proposed by the German physicist I.B. Listig (1808 – 1882). When mapping the earth's surface, based on many years of research by scientists, the complex geoid figure, without compromising accuracy, is replaced by a mathematically simpler one - ellipsoid of revolution. Ellipsoid of revolution– a geometric body formed as a result of rotation of an ellipse around a minor axis.
The ellipsoid of rotation comes close to the geoid body (the deviation does not exceed 150 meters in some places). The dimensions of the earth's ellipsoid were determined by many scientists around the world.
Fundamental studies of the figure of the Earth, carried out by Russian scientists F.N. Krasovsky and A.A. Izotov, made it possible to develop the idea of a triaxial earth ellipsoid, taking into account large geoid waves, as a result of which its main parameters were obtained.
In recent years (late 20th and early 21st centuries), the parameters of the Earth’s figure and external gravitational potential have been determined using space objects and the use of astronomical, geodetic and gravimetric research methods so reliably that now we are talking about assessing their measurements in time.
The triaxial terrestrial ellipsoid, which characterizes the figure of the Earth, is divided into a general terrestrial ellipsoid (planetary), suitable for solving global problems of cartography and geodesy, and a reference ellipsoid, which is used in individual regions, countries of the world and their parts. An ellipsoid of revolution (spheroid) is a surface of revolution in three-dimensional space, formed by rotating an ellipse around one of its main axes. An ellipsoid of revolution is a geometric body formed as a result of the rotation of an ellipse around a minor axis.
Geoid- the figure of the Earth, limited by the level surface of the gravity potential, which coincides in the oceans with the average ocean level and is extended under the continents (continents and islands) so that this surface is everywhere perpendicular to the direction of gravity. The surface of the geoid is smoother than the physical surface of the Earth.
The shape of the geoid does not have an exact mathematical expression, and to construct cartographic projections, the correct geometric figure is selected, which differs little from the geoid. The best approximation of the geoid is the figure obtained by rotating an ellipse around a short axis (ellipsoid)
The term "geoid" was coined in 1873 by German mathematician Johann Benedict Listing to refer to a geometric figure, more precisely than an ellipsoid of revolution, that reflects the unique shape of planet Earth.
An extremely complex figure is the geoid. It exists only theoretically, but in practice it cannot be touched or seen. You can imagine the geoid as a surface, the force of gravity at each point of which is directed strictly vertically. If our planet were a regular sphere filled evenly with some substance, then the plumb line at any point would point to the center of the sphere. But the situation is complicated by the fact that the density of our planet is heterogeneous. In some places there are heavy rocks, in others there are voids, mountains and depressions are scattered across the entire surface, and plains and seas are also unevenly distributed. All this changes the gravitational potential at each specific point. The fact that the shape of the globe is a geoid is also to blame for the ethereal wind that blows our planet from the north.
Be extremely careful, apparently we are destined to live in an extraordinary period of time associated with the inversion of the Earth’s magnetic field, and a complex of inversions of all objects in the solar system. A necessary process that ensures the existence of life on Earth, a process that stimulates the evolution of the entire biosphere. All information resources deliberately provide false information about this process and by all means hide the algorithm of the inversions of the precession cycle of the Solar system relative to the Zodiac during the period of the Plotonic year. The chronology systems were deliberately distorted, and many dates for the “end of the world” were deliberately promoted to create a skeptical majority opinion on this topic. A negative image of the “end of the world” was deliberately created for this process, which is extremely necessary for the existence of the biosphere. The global scenario of the third world war with the use of local nuclear strikes is deliberately being promoted, thereby providing the following legend, the future concealment of the main reason for the displacement of the magnetic poles with their future location along the line of the modern equator, with the coordinates of the first post-inversion second Z 1.3 deg. S.W. 58.87 gr. W. D, N 1.3 gr. S.W. 121.13 gr. V.D. From the moment the Solar System enters the Age of Aquarius, a 90 degree inversion of the geomagnetic field takes place relative to the original coordinates of the poles of the previous inversion. The transition to the previous two eras was accompanied by 30 degree inversions, the two subsequent eras of Capricorn and Sagittarius will also be accompanied by 30 degree inversions, the subsequent era of Scorpio will again be accompanied by a 90 degree inversion. With each inversion, the poles describe sinusoidal trajectories of one full period to future coordinates within one day. Thus, in the pricesian cycle during the Platonic year there are four 90 degree inversions and eight 30 degree inversions. Accordingly, each of them is accompanied by global events and global changes in both climate and landscape, as well as changes in the physical world and its properties, which actually provokes the disappearance of previous civilizations and the emergence of new ones. Ninety-degree inversions are accompanied by an equally important event, such as the crossing of the solar equator of one of the planets in the solar system, the existence of which is also deliberately hidden by the media and official natural sciences. The only planet that has the property of crossing the solar equator “Nibiru, aka Charon, aka Anubis”, crossing the equatorial structure of the Sun, passes into the visible range, which is actually the secret of its appearance and disappearance in the sky. And this is only a small part of the hidden and distorted information. The model of the Solar system is also deliberately distorted; in reality, it does not have a disk shape, but an hourglass shape where the center is the Sun; its equatorial structure is located perpendicular to the conical orbits of the planets in both the northern and southern hemispheres of its own magnetosphere. Accordingly, on the other side of the solar equator there is a similar planetary system with inversely proportional rotation cycles and all ongoing processes. And one planet directly in the equatorial structure of the Sun, where the equatorial structure itself performs the function of delimiting the range visible to humans. It was the function of delimiting the visible range of the solar equator that provided natural science with the opportunity to hide and distort such significant information. An equally important process is happening today with the Earth’s magnetosphere, associated with a drop in the intensity of all components of the magnetic field and their tendency to zero, a sure sign of an imminent inversion. The principle of pre-inversion zeroing is necessary for the revival of the next post-inversion pulse of all component values of the magnetosphere. Resetting values to zero is necessary to create conditions of harmony that do not allow values to resonate. The second condition is the emergence of a new pulse of hyper-low frequency with new characteristics of its components again providing the conditions for the existence of the biosphere for the period of the next era. Introducing all kinds of adjustments to the physical world, a new climate, new continents, ocean currents, calderas, mountain and river systems, wind roses and other natural changes that stimulate all living things to a new round of evolution. Accordingly, this process will be accompanied by a mass of destructive consequences associated primarily with the reshaping of the geoid of the Earth’s body, with the shift of tectonic plates, changes in the sea level of many landscapes, accompanied by giant tsunamis and storms. The trajectories of the movement of the poles to new coordinate points will instantly freeze, as will the territories of the newly formed polar systems. It is for this reason that animal bodies have been repeatedly discovered in permafrost. Many representatives of tropical flora and fauna were frozen into the polar glaciers. Paleontologists constantly find perfectly preserved remains of ancient animals and plants in permafrost - mammoths, saber-toothed tigers, palm trees with green leaves and ripe fruits, etc.
It was the impact of gigantic tsunamis long as the world's oceans and 90-degree inversions that formed coal basins, sweeping away everything in their path and burying everything swept away in the valleys in a thick layer of mud, sand and silt. Also, such rapid burials ensured the formation conditions and preservation of fossils of representatives of flora and fauna, and other artifacts of previous eras. It is known that all living beings who die these days decompose. The sleeping fish floats to the surface of the water and gradually begins to succumb to decomposition processes. The corpses of animals that die on land are either eaten by predators or quickly decompose. Dead plants are also destroyed in relatively short periods of time. How did the process of fossil formation take place in the past? The most logical explanation is that living things were quickly buried as a result of tidal activity, massive land shifts, and volcanic eruptions on a global scale. Important factors in subsequent fossilization processes were very high temperature and pressure. Sedimentary layers were thus not formed gradually over millions of years, but could be the result of a cataclysm. The fossil record is replete with examples that support this assumption. As mentioned above, accumulations of fossils in different areas of the planet indicate that living organisms once died suddenly. Developing this idea, let's look at examples. Fossilized remains of fish Well-preserved accumulations of fish of a wide variety of species have been discovered by scientists in many parts of the planet. How did fish end up in areas where there is no water these days, for example, high in the mountains?
Such tsunamis are capable of penetrating deep into continents, the main reason for their occurrence will be the newly formed equator, and the restructuring of the geoid of the planet’s body into a new sphere. It is for this reason that the fracture of lithospheric plates gives rise to mountain ranges where giant blocks of lithospheric plates stand almost vertically, forming rocky overhangs of young mountain systems. Due to the algorithm for the passage of inversions, all mountain systems are diverse in the time of their origin; there are more ancient ones like the Urals, and there are relatively young ones like the Alps. But they all arose in a very short period of time, almost within a few days, and this is absolutely obvious. In the process of rebuilding the geoid of the Earth's body from previous inversions, many artifacts found themselves under the water column of newly formed seas and oceans, ancient cities and various man-made structures of previous civilizations. The most important property of inversions is their passage at the moments of equinoxes and solstices, where the mixing of the polar and equatorial structure of the Earth’s magnetosphere gives rise to the property of shifting seasons, which is necessary for all forms of life during this period to ensure maximum conditions for their survival, where the new emerging a pulse of hyperlow frequency with the maximum amplitude of all component quantities of the magnetosphere.
Undoubtedly, official natural sciences will provide this information with a lot of counterarguments based on generally accepted theories, but we must not forget that these are just theories, for the most part, justified by facts of mathematical fitting, and nothing more.
But even despite a lot of counterarguments from official natural sciences, they can be discredited by obvious facts directly related to the Solar-Lunar cycle, contrary to official theories and explanations of this process. Most of our contemporaries observed with their own eyes the natural phenomenon of a Lunar Eclipse at the full moon, the gradually emerging and fading crescent shape of the uniformly illuminated lunar surface until complete shading by the Earth’s sphere, and the again growing crescent shape until the lunar surface was completely illuminated, until the visible full moon. Please pay attention to the fact that in this process we can see only sickle-shaped irregular shapes for the most part, and not exactly half of the lunar surface delimited by an even straight line, similar to the picture of the end of the first lunar phase. An even bigger question is raised by the illumination of the moon's surface by the second phase of the moon, regarding the generally accepted theory of shading of the Lunar sphere by the Earth's sphere, namely the visible illuminated part of more than half of the surface of the moon is obverse crescent-shaped. The scale of blatant outright lies is amazing, even taking into account the attempt of official natural sciences to rehabilitate themselves in this mistake, and come up with an even more ridiculous theory to explain the visible lunar cycle, crescent-shaped hemispheres and reverse crescent shapes, by the fact that the lunar sphere makes one revolution around the Earth in 29.5 days (by the way, the average statistical value) and we are provided with a picture of the illumination of the lunar sphere from different viewing angles during one cycle. Every artist and most ordinary people know that no matter the angle at which the sphere is illuminated, an unevenly illuminated spot will always be visible, in most cases of irregular shape, and uniformly illuminated crescent-shaped hemispheres and reverse crescent shapes will never be visible, because this is a sphere and not a disk. This is how they distort and hide the simple essence of obvious things. The explanation for this process looks different, the fact is that the main difference between the magnetosphere of the Earth and the Moon is that the Earth rotates its own body in a relatively stationary magnetosphere, the Moon rotates its own magnetic field around a relatively stationary body. In other words, we see the rotation of the equatorial ring of the Moon’s magnetic field and the delimitation of the spectrum visible to humans by the equatorial structure.
The official theory regarding the origin of lunar craters looks similar. The official theory of the origin of Moon craters boldly convinces us that their nature is the result of the fall of many meteorites and fireballs. The first thing you should pay attention to is that the diameter of the Earth is almost 4 times larger than the diameter of the Moon, and the Moon always faces the Earth with one side of the lunar craters. Secondly, all craters are round in shape and have different diameters, which means that all meteorite bodies had to fall along a strictly perpendicular trajectory relative to the surface of the Moon, this is the only way round craters can form. When a meteorite falls at any other angle, an oblong trail of irregular shape is formed, especially considering the density of the lunar surface. Third, given the difference in diameters of the Earth and the Moon, and the relative immobility of the Lunar sphere and the regular circumference of the craters, most of these craters should have been on Earth. Is this a paradox or a complete failure of natural sciences raised on an unprecedented lie? If you try to ask similar questions to servants of science, there is a 101 percent chance that the answer will be: “Well, this is because, due to certain circumstances, there are many references to different ununited sections of the same natural sciences, etc., etc. . up to the utopian theory of the singularity, the apogee of the servants."
Calculation of the astronomical era of the chronology system.
The calculation of the astronomical era is carried out according to the algorithm of the ratio of the number of complete lunar cycles to one astronomical year. The arithmetic mean value of one full Lunar cycle is ~29.5 days, in reality it ranges from 28.07 to 30.13 days and is calculated by the formation of one extra 13th month in relation to the astronomical year, since there are 354 Earth days in twelve lunar months. The calculation algorithm is based on the multiple of the period of formation of the 13th month in relation to the number of Earth astronomical years. Its full cycle is 45 astronomical years. The imperial dependence of numbers looks schematically.
Single 1. 365 days: divided by 12 + 1 month = 28.07
Double. 2. 365 × 2 ÷ (24+1) = 29.2
Threefold. 3. 365 × 3 ÷ 37 = 29.59
4. 365 × 4 ÷ 49 = 29.79
5. 365 × 5 ÷ 61 = 29.91
6. 365 × 6 ÷ 73 = 30
7. 365 × 7 ÷ 85 = 30.05
8. 365 × 8 ÷ 97 = 30.1
Nine times 9. 365 × 9÷109= 30.13
The sum of the nine results is exactly 266.84 divided by the number of multiple cycles, the result 29.64 is the arithmetic average of the duration of one Lunar cycle after 45 years. A full cycle of one astronomical era is equal to forty complete algorithms of 45 years, that is, 1800 Solar-Lunar cycles, which will correspond to 1860 Earthly astronomical years. Due to the main function of modification of the earth's magnetosphere during one astronomical era, associated with the displacement of the Earth's body within the structure of its own magnetosphere and the beginning of the movement of the poles from the initial post-inversion points coinciding with the geographical ones, along the Fibonacci spiral. According to the above-described algorithm for the multiplicity of Lunar cycles, each of the nine algorithms accounts for a total displacement of the poles by 1° along the trajectory of the Fibonacci spiral. This means that each dawn of the next multiple cycle will begin 4 minutes earlier, this is how the calendar system differs from the astronomical one, which ensures 365 days in one calendar year and the need to add one day for every fourth year. Another need to introduce a calendar system of chronology is aimed at concealing the process of shifting the equinoxes and solstices relative to the seasons and also requires the need for the so-called spring year. Since after one astronomical era, the magnetic poles make one full revolution along the trajectory of the Fibonacci spiral, which ensures the declination of the Earth’s axis relative to the ecliptic of the Sun, and winter will change with summer relative to the calendar months.
The same process explains the drop in the values of all components of the intensity of the Earth's magnetic field and the increase in their frequencies, for example Schumann.
They say about the Moon that it is a satellite of the Earth. The meaning of this is that the Moon accompanies the Earth in its constant movement around the Sun - it accompanies it. While the Earth moves around the Sun, the Moon moves around our planet.
The movement of the Moon around the Earth can generally be imagined as follows: either it is in the same direction where the Sun is visible, and at this time it moves, as it were, towards the Earth, rushing along its path around the Sun: then it passes to the other side and moves in the same direction. the direction in which our earth is rushing. But in general, the Moon accompanies our Earth. This actual movement of the Moon around the Earth can easily be noticed in a short time by any patient and attentive observer.
The proper movement of the Moon around the earth does not consist at all in the fact that it rises and sets or, together with the entire starry sky, moves from east to west, from left to right. This apparent movement of the Moon occurs as a result of the daily rotation of the Earth itself, that is, for the same reason that the Sun rises and sets.
As for the Moon’s own motion around the Earth, it affects itself in a different way: the Moon seems to lag behind the stars in their apparent daily motion.
Indeed: notice any stars in visible close proximity to the Moon on this particular evening of your observations. Remember more precisely the position of the Moon relative to these stars. Then, look at the Moon a few hours later or the next evening. You will be convinced that the Moon is behind the stars you noticed. You will notice that the stars that were on the right of the Moon are now further from the Moon, and the Moon has become closer to the stars on the left, and the closer the more time has passed.
This clearly indicates that, moving apparently for us from east to west, due to the rotation of the Earth, the Moon at the same time slowly but steadily moves around the Earth from west to east, completing a full revolution around the Earth in about a month.
This distance is easy to imagine by comparing it with the apparent diameter of the Moon. It turns out that in one hour the Moon travels a distance in the sky approximately equal to its diameter, and in a day - an arc path equal to thirteen degrees.
The dotted line shows the orbit of the Moon, that closed, almost circular path along which, at a distance of about four hundred thousand kilometers, the Moon moves around the Earth. It is not difficult to determine the length of this huge path if we know the radius of the lunar orbit. The calculation leads to the following result: the orbit of the Moon is approximately two and a half million kilometers.
There is nothing easier to obtain now and the information we are interested in about the speed of the Moon around the Earth. But for this* we need to know more precisely the period during which the Moon will cover this entire huge path. By rounding, we can equate this period to a month, that is, approximately equal to seven hundred hours. Dividing the orbital length by 700, we can establish that the Moon covers a distance of approximately 3600 km in an hour, that is, about one kilometer per second.
This average speed of the Moon shows that the Moon is not moving as slowly around the Earth as it might seem from observations of its displacement among the stars. On the contrary, the Moon is rapidly rushing along its orbit. But since we see the Moon at a distance of several hundred thousand kilometers, we barely notice its rapid movement. So the courier train, which we observe in the distance, seems to be barely moving, while it rushes past nearby objects with extreme speed.
For more accurate calculations of the Moon's speed, readers can use the following data.
The length of the lunar orbit is 2,414,000 km. The period of revolution of the Moon around the Earth is 27 days 7 hours. 43 min. 12 sec.
Did any of the readers think that there was a typo in the last line? Shortly before (p. 13) we said that the cycle of the lunar phases takes 29.53 or 29% of the day, and now we indicate that a full revolution of the Moon around Earth occurs in 27 g/z days. If the indicated data is correct, then what is the difference? We will talk about this a little further.
The Moon revolves around the Earth in an elliptical orbit, making a full revolution in one month in its own motion (average distance 385 thousand km). The plane of its orbit makes an angle with the plane of the ecliptic equal to 508. During the day, the Moon moves in orbit against the daily rotation of the sphere by approximately 13.2. Therefore, the daily change in right ascension averages 13.2 and ranges from10 to17 per day; daily changes in declination range from fractions of a degree to7, and the largest change per month reaches5-7. Due to the influence of the Earth, the period of revolution of the Moon around the Earth is approximately equal to the period of its rotation around its axis and therefore the Moon faces the Earth with one side. In addition to its own motion, the Moon, like all luminaries, exhibits diurnal motion, which is a consequence of the Earth’s rotation around its axis. The combined proper and daily motion of the Moon occurs in spirals.
Since in one day the Moon moves back in its own motion, against the daily movement, by 13.2, the moments of the Moon’s culmination in relation to the stars are delayed by 53 minutes every day. The daily lag of the Moon from the Sun is 12.2, and, therefore, the period of one daily revolution of the Moon around the Earth is 49 minutes longer than that of the Sun.
The period of time during which the Moon makes a complete revolution in its orbit relative to the fixed stars in its own motion is called a sidereal month. Its duration is 27.32 days.
The period of time during which the Moon makes a full revolution relative to the Sun, which also has its own movement, is called a lunar or synodic month. Its duration is 29.53 days.
Phases and age of the Moon. The moon is a dark body and can only reflect the light of the sun's rays. Depending on the position of the Moon in relation to the Earth and the Sun, the observer will see more or less of the illuminated surface of the Moon. Therefore, it is customary to say that the Moon is in different phases (Fig. 3.12.), the illumination boundary is called the terminator.
There are four main phases of the Moon:
new moon: Moon in position L 1;
The sun illuminates its far side, but an earthly observer does not see the Moon; first quarter:
Moon in position L 3; the observer sees a half-disk convex to the right; full moon:
Moon in position L 5; the observer sees the West disk;
last quarter:
Moon in position L 7; the observer sees a half-disk convexly facing to the left.
The moon passes through all phases in 29.53 days. The number of days that have passed from the new moon to this phase is called the age of the moon (B). In the daily MAE tables, the age of the Moon is indicated for each day of the year with an accuracy of 0 d.1, and the phases are depicted for a three-day interval by one of eight different icons showing the size of the illuminated part of the lunar disk.
The new and full moon phases in navigation are also called syzygies (B 0 and 15), and the phases of the first and last quarter are called quadratures (B 7 and 22).
The mutual motion of the Moon around the Earth, and the Earth around the Sun, explains the possibility of lunar and solar eclipses.
Both the Earth and the Moon, like dark bodies, cast a cone of shadow from themselves into cosmic space. Obviously, the cone of the Earth's shadow will be significantly larger than the cone of the Moon's shadow (the diameter of the Moon is approximately equal to ¼ of the diameter of the Earth).
A lunar eclipse occurs when the Moon, in its own motion, falls into the cone of the Earth's shadow (full moon phase).
As can be seen from the figure, a solar eclipse can be observed only on a small area of the earth's surface; An eclipse of the Moon is visible to observers of the entire earthly hemisphere facing the Moon.
If the plane of the Moon’s orbit always coincided with the plane of the Earth’s orbit and the distance of the Moon from the Earth remained unchanged, then every full moon we would observe an eclipse of the Moon, and every new moon a number of observers could see an eclipse of the Sun.
In reality, such a situation is only a special case and relatively rare for the mutual motion of these luminaries. In general, the orbits of the Moon and the Earth do not coincide (inclination angle 58), and the distances to the Moon range from 59 to 61 Earth radii.
Therefore, in general, solar and lunar eclipses are very complex phenomena and have a variety of forms. They may not exist at all if the Moon passes outside the cone of the Earth's shadow, and the cone of the Moon's shadow does not fall on the Earth. A solar eclipse can be total, but it can also be partial, when only part of the solar disk is covered by the shadow of the Moon; it can also be ring-shaped, when the shadow of the Moon covers only the central part of the solar disk, and its outer edges remain illuminated.
Apparent motion of planets in the celestial sphere
Planets that orbit the Sun like Earth will have visible movements, which is where they get their name “wandering stars.”
Planets whose orbits lie inside the Earth’s are called inferior planets and can occupy the following characteristic positions relative to the Earth (Fig. 3.14): inferior conjunction (point a) between the Sun and the Earth; superior conjunction (point b) “behind the Sun”. Elongation (western at point c and eastern at point d) is the greatest angular distance of the planet from the Sun (for Venus no more than 48, Mercury 28).
Rice. 3.14. Rice. 3.15.
Planets whose orbits lie outside the orbit of the Earth are called the upper planets and can occupy the following positions (Fig. 3.14.): opposition n, when the Earth is between the Sun and the planet (if the distance is minimal, the opposition is called great); conjunction b, when the planet is “behind the Sun”; quadratures K and K, when the difference in longitude of the Sun and the planet is 90.
If we obtain the andplanets from the results of observations and plot its visible path on a sphere or map, we will get a curve that is close to the ecliptic, but has a more complex character, often with loops and zigzags.
The apparent motion of planets on a sphere is explained by their movement in orbits in the same direction, but at different speeds. As the lower planet moves, its illuminated part either turns toward the Earth or away from the Earth, i.e. the planet, similar to the Moon, is visible in different phases; the upper planets do not experience phase changes.
For marine observations, only the four brightest planets are used: Venus, Mars, Jupiter and Saturn. The brightness and visibility conditions of these so-called “navigation” planets change depending on the distance to the Earth, the phase of Venus and their position on the sphere.
The inferior planet Venus in superior and inferior conjunctions is lost in the rays of the Sun and is not visible from Earth. In position c—western elongation—Venus is visible in the morning before sunrise; in eastern elongation d - in the evening before sunset. Venus reaches its greatest brightness - about -4 m2 - in phase 0.25, when a quarter of the disk is visible, since in this position it is much closer to the Earth than in the full disk phase.
The brightest planets - Venus and Jupiter - are visible in the sky even with the Sun, but only through the astronomical tube of the sextant. At this time, it is possible to determine the location using simultaneous observations of, for example, Venus and the Sun.
The upper planets - Mars, Jupiter and Saturn - are invisible only near conjunction, when they are lost in the rays of the Sun. The brightness of these planets varies widely. Thus, Mars usually has a brightness of about 1 m, and during a great opposition its brightness increases to – 2 m.5. The brightness of Jupiter ranges from – 2.5 to – 1 m.5.
"Navigation" planets can be identified relatively easily. Venus is always close to the Sun, so it is visible only as a bright white “evening or morning star”. Mars is reddish-orange, Jupiter is yellowish, and Saturn is white. All planets are characterized by the absence of flicker, noticeable even in the brightest stars. The visibility conditions of the planets for each month of a given year are indicated in yearbooks.