Types of lunar eclipses. What is a lunar eclipse and how does it happen

> Lunar eclipse

What's happened moon eclipse : characteristics of the phenomenon and its essence, formation scheme, lunar eclipse calendar, full, partial, penumbral with photo, how to observe.

In fact, an eclipse is the complete or partial obscuration of one object in the sky by another. In this way, moon eclipse- this is the immersion of the moon in the cone of the earth's shadow. In this case, our planet is located on a line between the center of the Moon and the center of the Sun. The phenomenon occurs with a serious decrease in the brightness of the moon's disk.

Objects in space move, so the displacement of the shadow across the lunar surface creates the phases of the moon during an eclipse. It is customary to distinguish penumbral (the Moon plunges only into the penumbra of the Earth), partial (at the peak of the eclipse, only part of the lunar disk plunges into the Earth's shadow) and total (the lunar disk completely enters the Earth's shadow) lunar eclipses. That is, by understanding the level of the Moon's immersion in the Earth's shadow, you can understand what kind of lunar eclipse you are looking at. Observations of such phenomena can be carried out in any corner of the world where the Moon is located above the horizon. The average duration of an eclipse is several hours.

As stated above, lunar eclipses only occur on a full moon. If we imagine that the Moon revolves around our planet in the same plane in which the Earth revolves around the Sun, then observers could admire lunar eclipses every full moon. However, the plane of the lunar orbit is at an angle of 5˚ to the plane of the ecliptic, so moon eclipse occurs only if the moon approaches the nodes of its orbit. The entry of the full moon and new moon into the zone of the lunar nodes makes lunar and solar eclipses related.

Lunar eclipse calendar

Lunar eclipse calendar indicates the dates and year of future lunar eclipse events. You can see what would be the best field of view on Earth, indicating the point of maximum phase and the area of ​​distribution of the lunar eclipse. In addition, you can see the dates of past and future lunar eclipses, where the frequency and interval between eclipses is noticeable.

Lunar eclipse: basic concepts

Incredibly beautiful cosmic phenomenon that is observed a large number of people, but in the description there may be not entirely clear terms and phases familiar to astronomy. Let's study them carefully. Also remember what conditions are needed for the onset of a lunar eclipse when the Blood Moon appears and how this is affected by the distance of the satellite from the Earth.

Occurs at the moment when the moon is completely immersed in shadow space. The total phase of the eclipse lasts up to 1.5 hours, then the edge of the Moon appears again in the field of view.

An eclipse occurs at the moment when the moon is immersed in the shadow of only one edge, and part of its surface remains illuminated.

Around the cone of the Earth's shadow there is a space where the Earth only partially obscures the Sun. In the event that the Moon crosses the penumbra region, but does not plunge into the shadow, a penumbral eclipse is noted. At this point, the moon's brightness slightly weakens. It is almost impossible to notice it with the naked eye. And only during the period when the Moon approaches the cone of full shadow under conditions clear sky you can see a slight darkening from one edge of the moon.

The moment of greatest eclipse is an event that is characterized by the smallest distance between the axis of the Moon's shadow cone and the center of our planet. The point of greatest eclipse is the area of ​​the earth's surface where the maximum phase of the eclipse can be observed at the moment of the greatest eclipse.

The essence of the lunar eclipse

The minimum distance from the surface of our planet to the Moon is about 363 thousand kilometers. At the same time, the size of the shadow that the Earth is capable of creating at such a distance is approximately 2.5 times larger than the diameter of the Moon itself. Therefore, it is able to completely close the moon. An eclipse occurs when the Moon enters the cone of the Earth's shadow. If the shadow completely covers the lunar disk, a total lunar eclipse occurs. This process is clearly demonstrated by the diagram of a lunar eclipse.

In that part of the earth's surface where the Moon is above the horizon, it is possible to observe a lunar eclipse, and from any point its appearance will be the same. From the other half the globe the eclipse is not visible. Scientists have calculated that the maximum duration of one total lunar eclipse can be 108 minutes. Eclipses like this don't happen very often. The last long eclipses were observed on 08/13/1859 and 07/16/2000.

The degree of shadow coverage of the lunar surface at each moment of time is called the phase of the lunar eclipse. Zero phase is calculated as the ratio from the center of the moon to the center of the shadow cast by the earth. The astronomical values ​​of zero and phase are calculated for each moment of a lunar eclipse.

When the shadow of the Earth partially covers the Moon, it is called a partial eclipse. At the same time, part of the lunar surface is covered with a shadow, and part is illuminated by the sun's rays or remains in partial shade.

The region of space where our planet does not completely obscure the sun's rays, located along the perimeter of the cone of the cast shadow, is called penumbra. If the Moon does not go into shadow, but only falls into the penumbra region, then this phenomenon is called a penumbral eclipse. At the same time, the brightness of the Moon slightly decreases, which is almost imperceptible to the naked eye. Only at the moment of the passage of the Moon near the main cone of total shadow, there is a slight darkening on one side of the lunar disk. A penumbral eclipse can be observed using special instruments.

Since at the moment of a total eclipse the Moon is illuminated exclusively by rays that have passed through the upper layer of the atmosphere, depending on its state, the lunar disk becomes reddish or brownish in color. The difference in color can be traced by comparing pictures of lunar eclipses from different years.

For example, during the eclipse of 07/06/1982, the Moon had a reddish hue, and during the eclipse of 01/01/2000 it was slightly brownish. There are no blue or green solar eclipses because the Earth's atmosphere tends to scatter red rays to a greater extent.

Total lunar eclipses can vary in both color and brightness. To determine it, a special scale has been developed, which was named after the famous French astronomer Andre Danjon. The gradation of this scale has 5 divisions:

• zero division means the darkest eclipse, when the Moon is barely visible in the sky;
• one means a dark gray eclipse, when some details become visible on the lunar surface;
• a deuce indicates a grayish eclipse with a brownish tint;
• a light reddish-brown eclipse is indicated by a three;
• at the last brightest fourth type of eclipse, the moon becomes copper-red, during it, with the naked eye, you can see all the main details on the surface of the lunar disk.

If the Moon's orbit were in the plane of the ecliptic, then lunar eclipses, as well as solar eclipses, would be observed monthly. But, due to the fact that large quantity The time the Moon spends above or below the plane of the Earth's orbit, it falls into the shadow only twice a year. The angle of inclination of the plane of the lunar orbit with respect to the orbit of our planet is 5 degrees. Therefore, at the moments when the Moon is located in a straight line between the Earth and the Sun, an eclipse occurs. At the new moon, the moon covers sunlight, and on a full moon, it falls into the shadow of the Earth.

It happens that the interval between solar and lunar eclipses is small. At least 2 lunar eclipses can occur every year. Due to the fact that the lunar and earth orbits are in different planes, the phases of eclipses may differ. Moreover, eclipses of the same phase are repeated with a certain periodicity. This period is called saros and is 6585⅓ days (18 years 11 days and 8 hours). Thus, knowing the time of the previous eclipse, it is possible to determine with an accuracy of up to a minute when exactly the same next eclipse will occur in a particular area.

Such cyclicity is often used when determining the date and time of certain historical events described in old sources. First full eclipse was described in ancient Chinese chronicles. Having made certain calculations, scientists managed to find out that it dates back to 01/29/1136 BC. Information about three more eclipses is contained in the Almagest by Claudius Ptolemy and is dated 04/19/721 BC, 04/08/720 about AD. and 09/01/720 BC

Lunar eclipses are often mentioned in historical chronicles. For example, the famous commander of the Athenians Nikias was afraid of a lunar eclipse, a panic began in his army, because of which the Athenians were defeated. After some calculations, it was possible to establish the exact date this event (27.08.413 BC).

famous enough historical fact is the total lunar eclipse of 1504, which came to the aid of the expedition of Christopher Columbus. At that time they were in Jamaica and experienced difficulties with food and drinking water. Attempts to get hold of provisions from local Indians were unsuccessful. But Columbus knew for sure that on the night of March 1, a lunar eclipse would occur. He warned the leaders that if they did not deign to deliver travelers to the ship drinking water and food, he will steal the moon from the sky. With the onset of darkness, when the moon disappeared, the poorly educated Indians became very frightened and delivered everything they needed to the travelers. They begged to return the heavenly body to them, to which Columbus agreed. So the expedition managed to avoid starvation.

How to watch a lunar eclipse

The characteristics of lunar eclipses have already become available to you, but why are they so interesting to researchers? There are scientific benefits to be gained from observing lunar eclipses. Scientists collect and record materials on the state of the structure of the Earth's shadow and upper layers atmosphere. Amateur astronomers often photograph eclipses, make sketches of them, describing changes in the brightness of objects located on the lunar surface. The moments of the moon touching the shadow and those when it leaves its limits are accurately recorded. The moments of contact of the shadow with the largest objects on the lunar surface are also noted. Observations can be made with the naked eye, binoculars or a telescope. It is clear that the technique helps to more accurately record the results of observations.

In order to make observations most accurately, it is necessary to install on your telescope maximum magnification, aiming it directly at the touch points of the shadow and the lunar surface. This must be done in advance, a few minutes before the expected eclipse. Usually, all results are recorded in a special journal of observations of lunar eclipses.

The same exposure meter

If an amateur astronomer has at his disposal a photoexposure meter (a special device that allows you to measure the brightness of an object), he can independently plot the change in the brightness of the Moon's disk throughout the eclipse. To do this correctly, you need to install the device so that its sensitive element is directed to the center of the lunar disk.

I have seen an amazing lunar eclipse more than once. How it happens can be observed without special equipment, but, of course, it is better to use a telescope or a camera lens. Since the lunar eclipse is quite long, about 1.5 hours, even a beginner can prepare for this event and take great pictures. I think this is a great excuse to go out of town, into nature and enjoy the astronomical miracle.

Diagram of a lunar eclipse

It occurs during the following necessary conditions:

• full moon;
• the proximity of the Moon to the node of its orbit;
• the entry of the moon into the cone of the earth's shadow (if the shadow covers it completely, there will be a total lunar eclipse).

You can see a darkened celestial satellite anywhere on our planet in the same way, unlike solar eclipses, which are not visible everywhere.

Periodicity of lunar eclipses

In total, it was calculated that a maximum of 3 lunar eclipses occur per year, and a minimum - none. In exactly the same order, the event will occur no earlier than in 18 years.

Surprisingly, scientists can accurately calculate and determine at what time and in what place the next total eclipse of the heavenly body will occur. This cyclicality greatly helped researchers to find out the dates of historical events from records of lunar eclipses in ancient chronicles.

I smiled when, reading about Christopher Columbus, I learned such an interesting real fact. He was a literate and quick-witted man, and, knowing when the complete blackout of the Earth’s satellite would come, he frightened the leader of the Indians that he would take the Moon from them if he did not give water and food to his expedition. Horror gripped the Indians when they saw the foreigner's threat coming true, and began to beg him to "return" the night luminary, giving him what he asked for. Columbus was a good fellow and returned the “stolen” Moon to the sky.

It became interesting to me: “But if astronauts or, as is possible in our time, just space tourists find themselves on the Moon at this time, what will they see?” It turned out that the lunar guest at the time of its total eclipse can observe a total eclipse of the Sun!

A lunar eclipse occurs exclusively during the full moon phase and can only be observed over half of the earth's territory when the moon is above the horizon. The moon serves as a symbol of the soul, emotions, the ability to adapt to external circumstances. That is why it is so important to know what to do and what not to do during the period of such a phenomenon.

Lunar eclipse - what is it?

A lunar eclipse is the period when the Moon completely enters the cone of the shadow cast by the Earth. The moon does not have its own light, but its surface is able to reflect the sun's rays, so at night it always illuminates the dark road. During a shadowy dimming, our satellite turns red, which is why this phenomenon is often called a blood moon. It can be complete, when the shadow completely covers the Moon, or partial, when the Moon partially enters the Earth's shadow, one part of it remains dark, and the other is illuminated by the rays of the sun.

How is a lunar eclipse different from a solar eclipse?

During solar eclipse, the satellite completely or partially covers the solar disk. During a lunar eclipse, the Moon falls partially or completely into the cone-shaped shadow cast by the Earth, and instead of a bright disk, people see a dull reddish cloud. From an astronomical point of view, during a solar eclipse, the satellite comes between the Earth and the Sun, blocking the Earth's sunlight, meaning the Earth receives all the power of the Moon. With a shadowy dimming, the Earth becomes between the Sun and the Moon, it weakens the energy of the satellite, blocks the flow of solar energy to it.

There are certain conditions for the occurrence of lunar eclipses:

1. The Earth constantly casts a cone-shaped shadow from sunlight, this is because the Sun is larger in size than the Earth. The satellite must pass in the shadow part of the Earth.
2. For a blackout to occur, the moon must be in the phase of the full moon; during the new moon, the phenomenon is impossible.

In one year, a total lunar eclipse can occur no more than three times. Full cycle lunar eclipse repeats every eighteen years, and if weather will be good, you will definitely be able to observe such a phenomenon. You can observe it with the naked eye, and the chances of seeing such a phenomenon are much greater than the solar one, because it repeats much more often.

How does a lunar eclipse happen?

During a lunar eclipse, the disk of the satellite begins to gradually darken. When the entire visible surface of the satellite is already engulfed in shadow, as numerous descriptions of a lunar eclipse show, the dark disk changes color from light yellow to red-brown. This color provides valuable scientific data on the state of the atmosphere. He often caused bad associations and influenced the course of historical events. For example, in 1504 he helped the expedition of Christopher Columbus to get provisions from the local Indians.

Causes of a lunar eclipse

Eastern sages learned why a lunar eclipse occurs. This phenomenon happens on a full moon. During this period, the Sun, the satellite and the Earth are in a certain order in this straight line. Even if the Earth completely blocks the light of the Sun from the surface of the satellite, it can still be seen. Earth's atmosphere refracts sunlight and indirectly illuminates the moon. And the Moon acquires such a mysterious shade, because the earth's atmosphere is permeable to the rays of the red spectrum. Clouds and dust particles can change the color of the satellite.

In what phase can a lunar eclipse be observed?

The phase of the moon is the illumination of the satellite by sunlight, which changes periodically. Depending on the conditions of illumination of the Moon by the Sun, there are several phases:

• full moon;
• waning moon;
• new moon;
• Waxing Crescent.

A lunar eclipse is only possible on a full moon. The longest duration of such a phenomenon can be 108 minutes. There are cases when the satellite is not visible at all, but the phenomenon can be observed wherever it is above the horizon. Shady dimming accompanies solar. So, for example, if there was a solar eclipse during the New Moon phase, expect a total lunar eclipse on one of the next full moons.

Types of lunar eclipses

There are three types of dimming of the night star:

1. Complete. It can only occur on a full moon when the moon passes through the center of the Earth's total shadow.
2. Partial lunar eclipse when the shadow from the Earth darkens a small part of the Moon.
3. Penumbral. The full or partially illuminated part of the Moon passes through the penumbra of the Earth.

How does a lunar eclipse affect people?

Since the Moon is considered a symbol of his subconscious, a celestial phenomenon can cause mental imbalance and increased emotionality. During the period of such a phenomenon in society, an occurrence is possible. Most of all, people born on a lunar eclipse are susceptible to this, which is manifested by hysteria, crying, whims. Everything that a person has accumulated inside himself on a subconscious level breaks out. During a shadow blackout, a person is not guided by reason, but by feelings.

There are a number of people who are most susceptible harmful influence dimming:

1. Hypertension, increased risk of heart disease vascular system. Eliminate physical activity.
2. Mentally unhealthy people. This phenomenon is called "Eclipse of the Soul", all because the subconscious part triumphs over the conscious, which is why many become overly emotional.
3. People who have previously been hypnotized.

Lunar eclipse - interesting facts

In ancient times, people did not know that blackouts were common and were very frightened when they saw a blood red spot. All because at that time science was not yet so developed, the heavenly body seemed to narrow-minded people something unusual, mythical. But although science has already figured out the cause of such a phenomenon, there are various Interesting Facts about the lunar eclipse:

1. Earth is the only place in solar system where you can see this phenomenon.
2. Although a penumbral lunar eclipse occurs every eighteen years, there are people who have never seen such an event, because of their bad luck. For example, Canadian astronomer J. Campbell was unable to see the phenomenon due to bad weather.
3. Numerous studies by scientists have confirmed the fact that after 600 million years the satellite will move away from the Earth so much that it will no longer cover the Sun.
4. The shadow from the satellite moves at a speed of 2 thousand kilometers per second.

Is this a bad omen?

Lunar eclipses instilled real panic fear in ancient people. Entire generations of people considered lunar eclipses to be a bad omen, until man mastered science and some regularities of cosmic and universal scales. It was believed that the burgundy color of the moon is the approach of war, blood, death. Fortunately, science was able to remove the veil of mystery from this phenomenon, and all supernatural ideas about lunar eclipses have sunk into oblivion.

When do lunar eclipses occur?

They arise in certain time but only when the moon is full. At this time, the night luminary begins to pass away from the Earth, opposite to the Sun. Here the Moon can fall into the shadow that the Earth casts at this time. That's when people can watch.

How do lunar eclipses happen?

They happen differently than the sun. The fact is that the moon does not disappear completely, as the sun does during solar eclipse. The moon is only faintly visible. This happens for the following reason: part of the sun's rays, passing through the earth's atmosphere, is refracted in it and already enters the earth's shadow, falling directly on the moon. It is known that the air transmits red rays of light, which is why the night star becomes brown or copper-red.

It is known that the diameter of the Earth is exactly 4 times the diameter of the Moon. Accordingly, the shadow from the Earth is 2.5 times larger than the Moon. All this leads to the fact that the night luminary can sometimes completely enter the earth's shadow, which already causes a total lunar eclipse. Scientists have calculated and concluded that total lunar eclipses are longer than total solar eclipses, and can last up to 1 hour and 40 minutes!

According to the observations of astronomers, up to three lunar ones can occur in one year. It is worth noting that they repeat exactly after the same period of time as solar eclipses, which is 18 years 11 days and 8 hours. Scientists have even given a name to this period: saros (repetition). It is curious that saros was calculated in antiquity, so it is not difficult to calculate and predict the exact day. But to predict exact time its occurrence, as well as the conditions for its visibility - this is a more difficult task: different generations Astronomers have been studying the motion of the Moon and Earth for centuries to solve this problem. Currently possible mistakes in the calculations of the moments of the onset of lunar eclipses does not exceed 4 seconds!

A lunar eclipse is observed when the Earth's satellite enters the shadow that our planet casts from the Sun, that is, the Earth in this case is between the luminary and the Moon. In this case, the Moon can only partially fall into the shadow, and can be completely covered by it, therefore, partial and total eclipses are distinguished. Every year you can observe two or more lunar eclipses with different phases.

Instruction

When the Sun shines on the Earth, a cone of dense shadow forms on the other side of the planet, surrounded by penumbra. If the Moon at this moment partially or completely enters this cone, a lunar eclipse will be observed from the surface of the planet from the side where our satellite is visible. It does not look as impressive as the sun, but it is easier to observe it. The brightly lit Moon slowly begins to be covered, but remains visible due to scattered light in the Earth's atmosphere. sunbeams, which illuminate its surface with a reddish light. The eclipse can last longer, the Moon gradually comes out of the shadow and is again illuminated by the Sun. If the eclipse is partial, then only part of the satellite becomes dark. In some cases, the moon is not included in full shadow, but remains in penumbra - the eclipse is called penumbral.

On average, 2-3 lunar eclipses occur every year, but in some years this phenomenon is not observed at all, and in other years 4 or even 5 lunar eclipses can be seen. The number of eclipses varies from year to year with a certain frequency, which repeats every 18 years and 11 days. This period is called the saros or draconian period. During this period, there are 29 lunar eclipses - 12 less than solar ones. Two thirds of all eclipses are partial and one third are total.

The Moon shines with the reflected light of the Sun; therefore, when it falls into the shadow of the Earth (Fig. 30), it ceases to shine - a lunar eclipse occurs. Strictly speaking, the Moon continues to shine due to the fact that part of the Sun's rays, refracted in the Earth's atmosphere, illuminates the Moon, and we see it as a dark red disk. Blue rays are scattered in the earth's atmosphere, as a result, a person sees a blue sky during the day and a red Sun at sunset.

The shadow of the Earth has the shape of a cone, the cross-sectional diameter of which at the distance of the Moon is 2.5 times the diameter of the Moon, so the lunar eclipse lasts quite a long time. The maximum duration of a total lunar eclipse is 1 hour 45 minutes. The eclipse is visible throughout the night hemisphere of the Earth. The eclipse may be complete, if the Moon enters the shadow completely, or private, if only part of the Moon falls into the shadow.

When the shadow of the Moon falls on the Earth, a solar eclipse occurs (Fig. 30). It may be complete where the shadow falls and private in the area in the lukewarm. If at the time of the eclipse the Moon is at the point of the orbit farthest from the Earth, and the Earth is at the point closest to the Sun, then the Moon’s disk does not completely cover the Sun’s disk, and annular eclipse.

The shadow of the Moon draws on the Earth a long strip with a width of no more than 200 km, the width of the penumbra can be several thousand kilometers. Therefore, total solar eclipses are seen very rarely in each specific area, on average once every 300 years. In Moscow, the next total solar eclipse will be in 2126 (the previous one was in 1887). The maximum duration of a total solar eclipse (at the equator) is 7.5 minutes. In areas far from the equator, the eclipse, as a rule, lasts no more than 2-2.5 minutes.

An eclipse can only occur on a full moon (lunar) or a new moon (solar). Figures 31, 32 show the projections onto the celestial sphere of the disks of the Moon and the Sun for the moments of three successive new moons and two successive full moons. The angle between the ecliptic and the lunar orbit is greatly exaggerated.

Transit of Venus across the disk of the sun

Twice a century, Venus passes between the Earth and the Sun so that its disk is projected onto the disk of the Sun (Fig. 9). Such a passage, for example, took place on June 8, 2004 at 9:10–20 am Moscow time. It lasted about 6 hours (for each place of observation, the time of the beginning and end of the passage is slightly different). You need to observe the passage on a screen onto which the image of the Sun is projected. The planet is visible as a small dark circle moving against the background of the Sun's disk. If the diameter of the projection of the solar disk is 10 cm (which is available to the school telescope), then the diameter of the projection of Venus is 3 mm. naked eye(protected by a dense filter) it can only be seen by people with very sharp eyesight. It is very interesting to observe the moment when the planet crosses the edge of the solar disk. It was at such a moment, in 1761, that M. V. Lomonosov noticed that the disk of Venus, which had already partially crossed the edge of the disk, was surrounded by radiance (Fig. 10). He quite correctly concluded that this is the result of the refraction of the light of the Sun in the upper layers