As you know, on August 11, 2018, a partial solar eclipse will occur - and in light of this event, many should be interested - what is the essence of a solar eclipse, why does it happen?
Why does a solar eclipse occur?
As you know, planets and their satellites do not stand still. The Earth revolves around the Sun, and the Moon revolves around the Earth. And from time to time, moments arise when the Moon, in its movement, completely or partially obscures the Sun.
Picture 1. Solar eclipse diagram Solar eclipse- This is the shadow of the Moon on the surface of the Earth. This shadow is about 200 km in diameter, which is many times smaller than the diameter of the Earth. Therefore, a solar eclipse can be observed simultaneously only in a narrow strip along the path of the lunar shadow:
Moon shadow on the Earth's surface during a solar eclipse If the observer is in the shadow band, he sees total solar eclipse,
in which the Moon completely hides the Sun. At the same time, the sky darkens and stars can become visible. It's getting a little cooler. The birds suddenly fall silent, frightened by the sudden darkness, and try to hide. Animals begin to show anxiety. Some plants curl their leaves.
Phase of a total solar eclipse Observers close to the total eclipse can see partial solar eclipse
. During a partial eclipse, the Moon does not pass across the solar disk exactly in the center, but only hides part of this disk. At the same time, the sky darkens much less than during a total eclipse; the stars are not visible on it. A partial eclipse can be observed at a distance of about 2 thousand kilometers from the total eclipse zone.
Partial solar eclipse A solar eclipse always occurs on a new moon. At this time, the Moon is not visible on Earth, because the side of the Moon that faces the Earth is not illuminated by the Sun (see Figure 1). Because of this, it seems that during an eclipse the Sun is covered by a black spot that came from nowhere.
The shadow that the Moon casts towards the Earth looks like a sharply converging cone. The tip of this cone is located a little further than our planet (see Figures 1 and 2). Therefore, when a shadow falls on the Earth’s surface, it is not a point, but a relatively small (150–270 km across) black spot. Following the Moon, this spot moves across the surface of our planet at a speed of about 1 kilometer per second:
Scheme of the solar eclipse on August 11, 2018 from the NASA website Consequently, the shadow of the Moon moves at high speed along the earth's surface and cannot cover any one place on the globe for a long time. The maximum possible duration of the full phase is only 7.5 minutes. A partial eclipse lasts about two hours.
Solar eclipses on Earth are truly unique phenomena. It is possible because on the celestial sphere the diameters of the Moon and the Sun almost coincide, despite the fact that the diameter of the Sun is almost 400 times the diameter of the Moon. This happens because the Sun is about 400 times farther from the Earth than the Moon.
But the Moon's orbit is not circular, but elliptical. Therefore, at moments favorable for the onset of eclipses, the lunar disk can be larger than the solar disk, equal to it, or smaller than it. In the first case, a total eclipse occurs. In the second case, a total eclipse also occurs, but it lasts only a moment. And in the third case, an annular eclipse occurs: a shining ring of the Sun’s surface is visible around the dark disk of the Moon. Such an eclipse can last up to 12 minutes.
How will a partial solar eclipse occur on August 11, 2018?
On August 11, 2018, there will be a new moon and a partial eclipse of the Sun (max phase 0.74) with visibility in the north and east of Russia. The region of its best visibility falls in the subpolar latitudes of the northern hemisphere.
At 11:40 Moscow time the penumbra of the Moon will enter Russian territory, moving from the Murmansk region to the southeast. Most of the territory of our country will fall within the visibility area of the eclipse, except for the southwestern regions, where the Moon will pass the Sun in the sky, and the Chukotka and Kamchatka peninsula, where the Sun will have time to set below the horizon.
The eclipse reaches its maximum at a point with coordinates 70.4° north latitude, 174.5° east longitude. The maximum phase of the eclipse on Earth, equal to 0.74, will occur at 12:46 Moscow time at sunset near Wrangel Island, as well as on Chukotka (0.736). But even with such a fairly large phase, the darkening of the sky will not be visible.
At the time of the eclipse, the Sun will be in the constellation Leo.
This is the third partial solar eclipse of 2018. 2018 gave us three solar eclipses - February 15, July 13 and August 11. All solar eclipses are partial. These partial eclipses of the Sun were observed only in the circumpolar regions of the southern (15.02 and 13.07) and northern (11.08) hemispheres of the Earth.
Solar eclipses occur only when the Moon is between the Earth and the Sun (new moon phase). Between two and five solar eclipses can occur during the year.
An eclipse of the Sun in which the earth's surface is crossed only by the lunar penumbra (the cone of the shadow and its continuation do not cross the earth's surface) is called private.
On August 11, 2018, the axis of the lunar shadow passes near the north pole without crossing the surface of the Earth; the minimum distance from the center of the Earth to the axis of the lunar shadow cone is 7319 kilometers.
What is a total solar eclipse like?
During a total solar eclipse, you can observe the solar corona - the outer layers of the Sun's atmosphere. The Earth, like other planets, are located inside the corona. It consists of a rarefied gas with a temperature of about a million degrees.
Here in this picture you can very clearly see at what moment the crown is noticeable to us. The photographer superimposed photographs taken sequentially on top of each other: with each frame, the Moon obscures the solar disk more and more until it is completely hidden behind the silhouette of the Moon. At this moment (and it lasted only about two minutes) the solar corona is visible around the Moon:
2-3 seconds before the onset of a total eclipse, when the Moon has almost completely covered the Sun, bright ruby dots appear on the left solar edge, separated by dark intervals - these are Bailey's rosary. This happens because the solar disk still appears between the lunar mountains or lunar craters, which at that time were on the edge of the lunar disk.
Also, during an eclipse, you can observe red or orange flashing protrusions - these are prominences.
(photo by Alan Friedman)
And when the total phase of the eclipse comes to an end (or a second before the start), the sunlight emerging from behind the edge of the lunar disk creates a short-term effect of a diamond ring in the sky.
Interestingly, the earliest realistic depiction of a diamond ring, a crown, and a solar eclipse in general was made in 1735 by a German artist named Cosmas Damian Azam.
An eclipse is an astronomical situation in which one celestial body completely blocks the light of another celestial body. The most famous are the eclipses of the Moon and the Sun. Eclipses are considered interesting natural phenomena, familiar to humanity since ancient times. They occur relatively often, but are not visible from every point on the earth. For this reason, eclipses seem to be a rare event to many. As everyone knows, planets and their satellites do not stand in one place. The Earth revolves around the Sun, and the Moon moves around the Earth. Periodically, moments arise when the Moon completely or partially covers the Sun. So why do solar and lunar eclipses occur?
Moon eclipse
During its full phase, the moon appears coppery red, especially as it approaches the center of the shadow region. This shade is due to the fact that the rays of the sun, tangent to the surface of the earth, passing through the atmosphere, are scattered and fall into the shadow of the Earth through a thick layer of air. This works best with rays of red and orange shades. Therefore, only they paint the lunar disk this color, based on the state of the earth’s atmosphere.
Eclipse of the sun
A solar eclipse is the lunar shadow on the surface of the Earth. The diameter of the shadow spot is about two hundred kilometers, which is several times smaller than the earth. For this reason, an eclipse of the sun can only be seen in a narrow strip along the path of the moon's shadow. An eclipse of the Sun occurs when the Moon comes between the observer and the Sun, blocking it.
Since the Moon on the eve of an eclipse is turned towards us with the side that does not receive light, a new moon always occurs on the eve of an eclipse of the Sun. Simply put, the Moon becomes invisible. It seems that the Sun is covered by a black disk.
Why do solar and lunar eclipses occur?
The phenomena of solar and lunar eclipses are clearly observed through. Observers were able to achieve great achievements by confirming the effect of gravity of large space objects on light rays.
Every person has observed a solar eclipse at least once in their life or at least heard about it. This phenomenon has attracted attention for a long time...Every person has observed a solar eclipse at least once in their life or at least heard about it. This phenomenon has long attracted attention - at all times it was considered a harbinger of misfortune, some peoples perceived it as God's wrath. It really looks a little creepy - the solar disk is completely or partially covered by a black spot, the sky darkens, and sometimes you can even make out stars on it. This phenomenon causes fear in animals and birds - they gather in flocks and seek shelter. Why does a solar eclipse occur?
The essence of this phenomenon is quite simple - the Moon and the Sun line up in one line, and thus our earthly satellite blocks the star. The Moon is much smaller than the Sun, but because it is much closer to the Earth, a person observing a solar eclipse will see it covering the entire solar disk.
A solar eclipse can be total or partial, depending on how much the Moon covers our star.
On average, 2 to 5 eclipses occur on Earth annually.
Sometimes you can observe a rare astronomical phenomenon - the so-called circular eclipse. At the same time, the Moon appears smaller than the Sun, and covers only its middle part, exposing the solar atmosphere. This type of eclipse is extremely valuable for researchers of the processes occurring on our star. It makes it possible to better view the upper layers of the Sun. In particular, such eclipses have greatly helped in the study of the solar corona. It happens that the Moon appears larger than the Sun, then the disk is so blocked that even the rays emanating from it are not visible from the Earth. This variety of eclipses is explained by the fact that the lunar orbit has an elongated ellipsoidal shape, so at different times of the year it is further or closer from the Earth.
Scientists have long found the answer to the question of how and why a solar eclipse occurs., saving humanity from prejudices towards this phenomenon. Moreover, it can now be predicted. This made it possible to take a fresh look at many historical events. Thus, chroniclers, describing battles and other important events, often mentioned that a solar eclipse occurred on that day, without giving the exact date. Now, thanks to the calculations of modern scientists, these dates have been restored.
Observations of the Moon explained the causes of eclipses. It is clear that solar eclipses can only occur during a new moon, that is, when the Moon is between the Earth and the Sun.
The Moon blocks the light of the Sun, casting a shadow on the Earth. In those places through which this shadow passes, a solar eclipse is observed.
A shadow strip 200-250 kilometers wide, accompanied by a wider penumbra, runs at high speed across the earth's surface. Where the shadow is thickest and darkest, a total solar eclipse is observed; it can last, at most, about 8 minutes: in the same place where the penumbra lies, there is no longer a total, but a particular, partial eclipse. And beyond this penumbra, no eclipse can be detected - the Sun still shines there.
So people finally found out why a solar eclipse occurs and, having calculated the distance from the Earth to the Moon, equal to 380 thousand kilometers, knowing the speed of movement of the Moon around the Earth and the Earth around the Sun, they could already determine with absolute accuracy when and where solar eclipses would be visible .
And when these hitherto mysterious heavenly phenomena became clear to people, people also realized that much of what was said in the Holy Scriptures did not correspond to reality. There is a fairy tale that on the day of Christ’s death the Sun darkened and “darkness reigned over the whole Earth from the sixth hour to the ninth hour.” And we know that this could not have happened. To do this, it was necessary to perform another miracle - to stop the movement of the heavenly bodies for three hours. But this is as absurd as the tale of Joshua, who ordered the Sun to stop.
Knowing the cause of a solar eclipse, it is easy to determine why lunar eclipses occur.
Lunar eclipses, as we can imagine, can only happen during the full moon, that is, when the Earth is between the Sun and the Moon. Falling into the shadow cast by our planet into space, the Earth's satellite - the Moon - is eclipsed, and since the Earth is many times larger than the Moon, the Moon no longer enters the dense shadow of the Earth for a few minutes, but for two to three hours and disappears from our eye.
People were able to predict lunar eclipses two thousand years ago. Centuries-long observations of the sky have made it possible to establish a strict, but rather complex periodicity of lunar and solar eclipses. But why they happened was unknown. Only after the discoveries of Copernicus. Galileo, Kepler and many other remarkable astronomers made it possible to predict the onset, duration and location of solar and lunar eclipses with accuracy down to the second. With almost the same accuracy, it is possible to establish exactly when solar and lunar eclipses occurred - one hundred, three hundred, a thousand or tens of thousands of years ago: on the eve of the battle of the Russian army, Prince Igor with the Polovtsians, on the birthday of the Egyptian pharaoh Psametikh, or on that distant day the morning when the progenitor of modern man first armed his hand with a stone.
Thus, we can conclude that solar or lunar eclipses do not at all represent any unusual celestial phenomena. They are natural, and, of course, there is and cannot be anything supernatural in these phenomena.
Eclipses of the Moon and Sun also happen quite often. Several such eclipses occur around the globe every year. Solar eclipses, of course, are observed only in certain places: where the shadow of the Moon runs across the globe, eclipsing the light of the Sun.
The period from 2018 to 2033 was chosen because... it is quite interesting in relation to solar eclipses visible from the territory of Russia and the CIS countries. During these years, 14 solar eclipses will be observed from the territory of our country, which include two total eclipses, two annular eclipses and 10 partial eclipses. Particularly interesting will be the annular solar eclipse on June 1, 2030, the band of the annular phase of which will pass through the entire country from west to east from Crimea to Primorye!
It is worth noting that, for example, in the period from 2034 to 2060 (twice as long), only two total and three annular solar eclipses will be observed in our country! The difference is obvious, so we can say that Russians and residents of the CIS are lucky with solar eclipses in the next fifteen years.
How do solar eclipses occur? The cause of solar eclipses is our celestial neighbor the Moon. The apparent diameters of the Sun and Moon as seen from Earth are approximately the same. This means that the Moon, moving in its orbit, at some point can completely (total eclipse) or partially (partial eclipse) cover the Sun (during the new moon phase).
A total solar eclipse is the most spectacular and spectacular astronomical phenomenon! If night falls in the middle of the day and stars become visible in the sky, this is quite impressive! Unfortunately, the visibility of such a phenomenon extends only to a small area where the lunar shadow falls. But as the lunar shadow moves, it forms a narrow strip on the Earth’s surface (on average about 200 kilometers wide). The length of such a strip is several thousand kilometers, but this is still not enough for a total eclipse of the Sun to be seen by all residents of the hemisphere of the Earth facing the daylight. Total solar eclipses can occur every six months, but due to the peculiarities of the Moon's movement in its orbit, they most often occur only once a year.
More information about the possibility of solar eclipses can be found, for example, in the book “Total Solar Eclipse of March 29, 2006 and Its Observation” (link at the end of the article).
Total solar eclipses can be observed from the same locality on average only once every 300 years. This makes it necessary to travel into the visibility range of the eclipse. A total solar eclipse is accompanied by a partial solar eclipse, which is visible on both sides of the total eclipse band, where the lunar penumbra falls. The farther from the central line of the eclipse, the less the disk of the Sun will be covered by the Moon. But the width of the stripe of a partial solar eclipse is much greater than that of a total eclipse, so partial eclipses can be observed from the same observation point much more often. Thanks to the large territory of our country, we can observe solar eclipses more often than residents of countries with a small territory.
There are only partial eclipses, when the shadow of the Moon passes above or below the polar regions of the Earth, and only the lunar penumbra falls on our planet, showing the appearance of a damaged Sun. An annular eclipse is different in that the Moon completely sets on the disk of the Sun, but cannot completely cover it due to its smaller apparent diameter (when the Moon is near its apogee, i.e. the point of its orbit farthest from the Earth). As a result, the solar ring around the dark disk of the Moon is visible from Earth.
It should be noted that a total eclipse in the European part of Russia will only be observed in 2061. If you look at the map of the bands of total and annular eclipses over 20 years, you can see how rare total solar eclipses are, even for such a large country as ours.
The next total solar eclipses in 2019 and 2020 will be observed in Chile and Argentina. Therefore, those who want to see this wonderful phenomenon as soon as possible need to prepare for a transatlantic flight!
But let’s return to the eclipses of the period 2018 - 2033 described here, and consider them in more detail.
For convenience, which can be downloaded and printed.
Solar eclipses in Russia and the CIS in 2018 - 2033
(world time)
The 2018 solar eclipse will be a partial one. It will occur at the new moon on August 11, and the eclipse band will cover the northeastern part of our country with a maximum phase of 0.736 in Chukotka. Residents of North America, Scandinavia and China will also see private phases. The duration of the eclipse will be slightly less than 3.5 hours. The eclipse will occur in the constellation Leo.
Another solar eclipse of 2019 will be annular. It will occur at the new moon on December 26, and a strip of the annular phase will pass through the Indian and Pacific oceans, crossing Arabia, southern India and Indonesia from west to east. The maximum duration of the annular phase will reach 3 minutes 40 seconds at a phase of 0.97. Residents of the southern regions of our country, countries of Africa, Asia and Australia will see private phases. The eclipse will occur in the constellation Sagittarius.
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The 2020 solar eclipse will be annular. It will occur at the new moon on June 21, and the ring-shaped phase will pass through Africa, the Arabian Peninsula and the Asian continent. The duration of the ring-shaped phase at the maximum of the phenomenon will reach only 38 seconds with a phase of 0.994. In this case, the thinnest ring of this eclipse will be observed. In Russia and the CIS, the eclipse band will cover the entire southern half of the country. The maximum phase of about 0.7 can be observed in the Central Asian CIS countries. The eclipse will occur in the constellation Taurus.
The 2022 solar eclipse will be a partial one. It will occur at the new moon on October 25, and the eclipse will cover the western half of Russia. The maximum eclipse phase of 0.861 will be available for observation from the territory of our country in Siberia. The eclipse will occur in the constellation Virgo.
The 2026 solar eclipse will be total. It will occur at the new moon on August 12, and the band of total eclipse will pass through the Atlantic and Arctic oceans, Western Europe and Russia. A total eclipse will be observed in Taimyr (the duration of the total phase is 2 minutes), and a partial eclipse will cover the Far North of the country. The eclipse will occur in the constellation Leo.
The 2029 solar eclipse will be a partial eclipse. It will occur at the new moon on June 12, and the eclipse will pass through the Arctic Ocean, as well as across North America and the Far North of our country. The maximum eclipse phase of 0.458 will be available for observation from North America. In Russia, the smallest phases of the eclipse will be visible (about 0.2 or less). The eclipse will occur in the constellation Taurus.
The 2031 solar eclipse will be annular. It will occur at the new moon on May 21, and the annular eclipse with a maximum phase of 0.959 will pass through the Indian Ocean, as well as across Africa, India and Indonesia. On the territory of our country, the eclipse will be observed in its southern part with small phases (Central Asian CIS countries). The eclipse will occur in the constellation Taurus.