Other assumptions are also made: the human brain represents the celestial dome not as a regular hemisphere, but slightly flattened towards the horizon. If so, then he considers objects on the horizon, including the Moon, to be more distant than those at the zenith. But the brain perceives the angular size of the Moon as the same as it actually is (about 0.5°); immediately introduces automatic correction for distance and obtains different images of the same object.
Sometimes you can hear assumptions about the influence of some atmospheric phenomena on the refraction of sunlight, which is then reflected from the Moon and affects its color. Or maybe the Earth and the Moon are simply closer to each other at this time? Such assumptions are closer to reality.
Environmentalists say the Moon's large size is caused by environmental pollution. But the ratio of the sizes of the Earth and man (and all of humanity with its activities) is equal to the ratio of an atom and an orange.
In fact
It is not necessary to observe an extremely large moon often. But the observer will notice that the larger-than-usual disk is always slightly redder. Redness can be caused by only one thing - the influence of what is between the eye and the Moon. It's a natural atmosphere. Or rather her condition. The higher its density, the greater its ability to increase. An example of this is the pebbles and stones located at the bottom of a transparent reservoir, which are always visible in a larger size than they actually are. Water is 100 times denser than air.Air density also varies depending on humidity and pressure. The atmosphere can sometimes be extremely saturated with moisture. During large-scale changes in weather conditions, significant masses of air above the observation site are in a more compressed state than usual. And the greater the thickness of dense air, the greater its ability to increase and distort light causing redness.
At the equator, the Earth's rotation speed is much greater than at the poles. Therefore, due to forces, the planet is pulled to the sides, and with it the atmosphere. At the equator it is thicker than in mid-latitudes.
Adding this factor to the distance in orbit, weather conditions, density and humidity - at the equator you can sometimes see the Moon in such a way that if you tell it, they won’t believe it.
Observing the Moon at the equator, you can see it in the new moon phase, inverted with its horns upside down, looking like a boat. In ancient times, Pacific sailors believed that this was the boat of the god of the sea, calling them to discover new lands.
Sources:
- Why does the Moon appear larger on the horizon?
The phenomenon of moon visibility is actually observed during the new moon. This happens due to several reasons. The side of the Moon, which is illuminated by the Sun, each time addresses the inhabitants of the Earth from a new angle, as a result of which a change in lunar phases appears. This process is not affected by the Earth's shadow except when the Moon is eclipsed during a full moon. This phenomenon occurs twice a year.
During the new moon, the Moon and the Sun interact in the following way: The Earth is combined with the Sun, as a result of which the sanctified part of the Moon becomes invisible. After it passes, it appears in the form of a narrow sickle, which gradually increases in size. This period is usually called the Moon.
As the earth's satellite moves along its orbit in the first quarter of the lunar cycle, the apparent distance of the Moon from the Sun begins to develop. A week after the new moon, the distance from the Moon to the Sun becomes exactly the same as the distance from the Sun to the Earth. At such a moment, a quarter of the lunar disk becomes visible. Further, the distance between the Sun and the satellite continues to grow, which is called the second quarter of the lunar cycle. At this moment, the Moon is at the farthest point in its orbit from the Sun. Its phase at this moment will be called the full moon.
In the third quarter of the lunar cycle, the satellite begins its reverse motion relative to the Sun, approaching it. shrinks back down to the size of a quarter disk. The lunar cycle ends with the satellite returning to its original position between the Sun and Earth. At this moment, the consecrated part of the Moon completely ceases to be visible to the inhabitants.
In the first part of its cycle, the Moon appears above the horizon, together with the rising Sun, it is at the zenith by noon and in the visible zone throughout the day until sunset. This picture is usually observed in and.
Thus, each appearance of the lunar disk depends on the phase in which the celestial body is at one time or another. In this regard, such concepts as a waxing moon, as well as a blue moon, appeared.
Students came up with many original holidays, one of which is “ Equator" It is celebrated by those who have reached exactly the halfway point of their studies at the institution. There is no exact date of celebration; each group or course chooses a day that is convenient. Approximate dates: end of February - beginning of March.
Instructions
Certain clear traditions of celebrating student " Equator a" also no. Everyone will have to decide together, choosing the best option based on financial capabilities and fun. " Equator” is often compared to the New Year: “As you celebrate the medium, the rest of your study time will pass!”
Use your collective imagination and come up with an unforgettable program. You can involve teachers and arrange an evening in the style of a skit party, with skits, humor and musical numbers. Diversify the festive program with drawings, jokes and competitions with prizes.
Prepare “gold medals”, “red diplomas” and other comic awards. Choose a beauty queen " Equator a”, present a certificate of commendation to the “honored botanist” of the course. For each student, you can choose a nomination so that there are no offended or deprived of attention.
Don’t arrange ordinary gatherings with feasting and dancing, this day is special, and you need to make it memorable for a long time. About the celebration " Equator a" you will tell your children, so organize a fun evening.
Of course, you can’t completely do without a treat. Solve this issue as a team. What exactly you will do - buy ready-made food or cook - depends on your finances. Although Olivier salad in a bowl is just right for a student!
Buy balloons - this way you can decorate the room quite well. Print out photos of passing " Equator» students, decorate them with cut-out pictures and make a large collage. For this landmark work, you can choose a theme, such as a famous cartoon. Or make a picture before the holiday, and during the party take photographs of everyone present and then make a “After the Equator” panorama.
If the weather is sunny on the chosen day, you can organize a couple of active competitions in nature. Running in sacks, tug of war, jumping in a gas mask with a skipping rope - all this will amuse and delight not only the students, but also all eyewitnesses of this event.
Each participant will undoubtedly make their contribution to the creation of your holiday " Equator a", which will be remembered by everyone for its brightness, humor and kindness.
Sources:
- "Equator". Student holiday traditions
- students' equator
Tip 4: Why does the moon appear larger at the horizon than at its zenith?
It is impossible to imagine the life of earthlings without the Moon. The night not only inspires poets, it made possible the very origin and preservation of life on Earth. At all times, the Moon has posed many questions to man.
Some mysteries of the Moon are still waiting to be solved. Scientists offer different hypotheses, but none explains everything. One such mystery is a phenomenon known as the “moon illusion.”
Moon illusion
This phenomenon can be observed by anyone, and you don’t need a telescope, just a clear sky. If you look at the night during its sunrise or sunset, i.e. at a time when the Moon is visible low above the horizon, and then look at it at its zenith, it is easy to notice that the diameter of the lunar disk changes. Low above the horizon it looks several times larger than high in the sky.
Of course, the size of the Moon itself cannot change; only how it looks from the point of view of an earthly observer changes.
How to explain
Attempts to explain this phenomenon were made back in Ancient Greece. It was then that the idea was expressed that the Earth’s atmosphere was to blame, but modern scientists do not agree with this. The rays of celestial bodies are indeed refracted in the atmosphere, but the apparent size of the Moon at the horizon does not increase because of this, but decreases.
The answer to the “increase” and “decrease” of Luga should be sought not so much in physical phenomena, but in the peculiarities of human visual perception. This can be proven with the help of a simple experiment: if you close one eye and look at some small object (for example, ) against the background of a “large” lunar disk above the horizon, and then against the background of a “small” Moon at the zenith, it turns out that the size ratio the disk and this item have not changed.
One of the hypotheses connects the “increase” of the lunar disk with its comparison with earthly landmarks. It is known that the greater the distance from the observer to the object, the smaller the projection of the object on the retina, the “smaller” it is from the point of view of the observer. But visual perception is characterized by constancy - constancy of the perceived size of objects. A person sees a distant object as distant, not small.
The lunar disk, located low above the horizon, is located “behind” houses, trees and other objects that a person sees, and is perceived as more distant. From the point of view of constancy of perception, this is a distortion of the perceived size, which must be compensated, and the “distant” Moon becomes “large”. When the Moon is visible at its zenith, there is nothing to compare its size with, so the illusion of enlargement does not arise.
Another hypothesis explains this phenomenon by divergence (divergence) and convergence (reduction) of the eyes. Looking at the Moon at its zenith, a person throws back his head, which causes divergence of the eyes, which has to be compensated by convergence. Convergence itself is associated with the observation of objects close to the observer, so the Moon at its zenith is perceived as a closer object than at the horizon. When maintaining disk size, "closer" means "smaller".
However, none of these hypotheses can be called flawless. The illusion of the Moon is waiting to be solved.
Sources:
- Why does the Moon appear large above the horizon, but small above your head?
In 1609, after the invention of the telescope, humanity was able to examine its space satellite in detail for the first time. Since then, the Moon has been the most studied cosmic body, as well as the first one that man managed to visit.
The first thing we have to figure out is what our satellite is? The answer is unexpected: although the Moon is considered a satellite, technically it is the same full-fledged planet as the Earth. It has large dimensions - 3476 kilometers across at the equator - and a mass of 7.347 × 10 22 kilograms; The Moon is only slightly inferior to the smallest planet in the Solar System. All this makes it a full participant in the Moon-Earth gravitational system.
Another such tandem is known in the Solar System, and Charon. Although the entire mass of our satellite is a little more than a hundredth of the mass of the Earth, the Moon does not orbit the Earth itself - they have a common center of mass. And the proximity of the satellite to us gives rise to another interesting effect, tidal locking. Because of it, the Moon always faces the same side towards the Earth.
Moreover, from the inside, the Moon is structured like a full-fledged planet - it has a crust, a mantle and even a core, and in the distant past there were volcanoes on it. However, nothing remains of the ancient landscapes - over the course of four and a half billion years of the Moon’s history, millions of tons of meteorites and asteroids fell on it, furrowing it, leaving craters. Some of the impacts were so strong that they tore through its crust all the way to its mantle. The pits from such collisions formed lunar maria, dark spots on the Moon that are easily visible from. Moreover, they are present exclusively on the visible side. Why? We will talk about this further.
Among cosmic bodies, the Moon influences the Earth the most - except, perhaps, the Sun. Lunar tides, which regularly raise water levels in the world's oceans, are the most obvious, but not the most powerful, impact of the satellite. Thus, gradually moving away from the Earth, the Moon slows down the rotation of the planet - a solar day has grown from the original 5 to the modern 24 hours. The satellite also serves as a natural barrier against hundreds of meteorites and asteroids, intercepting them as they approach the Earth.
And without a doubt, the Moon is a tasty object for astronomers: both amateurs and professionals. Although the distance to the Moon has been measured to within a meter using laser technology, and soil samples from it have been brought back to Earth many times, there is still room for discovery. For example, scientists are hunting for lunar anomalies - mysterious flashes and lights on the surface of the Moon, not all of which have an explanation. It turns out that our satellite hides much more than is visible on the surface - let's understand the secrets of the Moon together!
Topographic map of the Moon
Characteristics of the Moon
Scientific study of the Moon today is more than 2200 years old. The motion of a satellite in the Earth's sky, its phases and distance from it to the Earth were described in detail by the ancient Greeks - and the internal structure of the Moon and its history are studied to this day by spacecraft. Nevertheless, centuries of work by philosophers, and then physicists and mathematicians, have provided very accurate data about how our Moon looks and moves, and why it is the way it is. All information about the satellite can be divided into several categories that flow from each other.
Orbital characteristics of the Moon
How does the Moon move around the Earth? If our planet were stationary, the satellite would rotate in an almost perfect circle, from time to time slightly approaching and moving away from the planet. But the Earth itself is around the Sun - the Moon has to constantly “catch up” with the planet. And our Earth is not the only body with which our satellite interacts. The Sun, located 390 times farther than the Earth from the Moon, is 333 thousand times more massive than the Earth. And even taking into account the inverse square law, according to which the intensity of any energy source drops sharply with distance, the Sun attracts the Moon 2.2 times stronger than the Earth!
Therefore, the final trajectory of our satellite’s motion resembles a spiral, and a complex one at that. The axis of the lunar orbit fluctuates, the Moon itself periodically approaches and moves away, and on a global scale it even flies away from the Earth. These same fluctuations lead to the fact that the visible side of the Moon is not the same hemisphere of the satellite, but its different parts, which alternately turn towards the Earth due to the “swaying” of the satellite in orbit. These movements of the Moon in longitude and latitude are called librations, and allow us to look beyond the far side of our satellite long before the first flyby by spacecraft. From east to west, the Moon rotates 7.5 degrees, and from north to south - 6.5. Therefore, both poles of the Moon can be easily seen from Earth.
The specific orbital characteristics of the Moon are useful not only to astronomers and cosmonauts - for example, photographers especially appreciate the supermoon: the phase of the Moon in which it reaches its maximum size. This is a full moon during which the Moon is at perigee. Here are the main parameters of our satellite:
- The Moon's orbit is elliptical, its deviation from a perfect circle is about 0.049. Taking into account orbital fluctuations, the minimum distance of the satellite to the Earth (perigee) is 362 thousand kilometers, and the maximum (apogee) is 405 thousand kilometers.
- The common center of mass of the Earth and the Moon is located 4.5 thousand kilometers from the center of the Earth.
- A sidereal month - the complete passage of the Moon in its orbit - takes 27.3 days. However, for a complete revolution around the Earth and a change in lunar phases, it takes 2.2 days more - after all, during the time that the Moon moves in its orbit, the Earth flies a thirteenth part of its own orbit around the Sun!
- The Moon is tidally locked into the Earth - it rotates on its axis at the same speed as around the Earth. Because of this, the Moon is constantly turned to the Earth with the same side. This condition is typical for satellites that are very close to the planet.
- Night and day on the Moon are very long - half the length of an earthly month.
- During those periods when the Moon comes out from behind the globe, it is visible in the sky - the shadow of our planet gradually slides off the satellite, allowing the Sun to illuminate it, and then covers it back. Changes in the illumination of the Moon, visible from the Earth, are called ee. During the new moon, the satellite is not visible in the sky; during the young moon phase, its thin crescent appears, resembling the curl of the letter “P”; in the first quarter, the Moon is exactly half illuminated, and during the full moon it is most noticeable. Further phases - the second quarter and the old moon - occur in the reverse order.
Interesting fact: since the lunar month is shorter than the calendar month, sometimes there can be two full moons in one month - the second is called a “blue moon”. It is as bright as an ordinary light - it illuminates the Earth by 0.25 lux (for example, ordinary lighting inside a house is 50 lux). The Earth itself illuminates the Moon 64 times stronger - as much as 16 lux. Of course, all the light is not our own, but reflected sunlight.
- The Moon's orbit is inclined to the Earth's orbital plane and regularly crosses it. The satellite's inclination is constantly changing, varying between 4.5° and 5.3°. It takes more than 18 years for the Moon to change its inclination.
- The Moon moves around the Earth at a speed of 1.02 km/s. This is much less than the speed of the Earth around the Sun - 29.7 km/s. The maximum speed of the spacecraft achieved by the Helios-B solar probe was 66 kilometers per second.
Physical parameters of the Moon and its composition
It took people a long time to understand how big the Moon is and what it consists of. Only in 1753, the scientist R. Bošković was able to prove that the Moon does not have a significant atmosphere, as well as liquid seas - when covered by the Moon, the stars disappear instantly, when their presence would make it possible to observe their gradual “attenuation”. It took another 200 years for the Soviet station Luna 13 to measure the mechanical properties of the lunar surface in 1966. And nothing was known at all about the far side of the Moon until 1959, when the Luna-3 apparatus was able to take its first photographs.
The Apollo 11 spacecraft crew returned the first samples to the surface in 1969. They also became the first people to visit the Moon - until 1972, 6 ships landed on it and 12 astronauts landed. The reliability of these flights was often doubted - however, many of the critics' points were based on their ignorance of space affairs. The American flag, which, according to conspiracy theorists, “could not have flown in the airless space of the Moon,” is in fact solid and static - it was specially reinforced with solid threads. This was done specifically in order to take beautiful pictures - a sagging canvas is not so spectacular.
Many distortions of colors and relief shapes in the reflections on the helmets of the spacesuits in which counterfeits were sought were due to gold plating on the glass, which protected against ultraviolet. Soviet cosmonauts who watched the live broadcast of the astronaut landing also confirmed the authenticity of what was happening. And who can deceive an expert in his field?
And complete geological and topographic maps of our satellite are being compiled to this day. In 2009, the Lunar Reconnaissance Orbiter (LRO) space station not only delivered the most detailed images of the Moon in history, but also proved the presence of large amounts of frozen water on it. He also put an end to the debate about whether people were on the Moon by filming traces of the activities of the Apollo team from low lunar orbit. The device was equipped with equipment from several countries, including Russia.
Since new space states like China and private companies are joining the lunar exploration, new data is arriving every day. We have collected the main parameters of our satellite:
- The surface area of the Moon occupies 37.9x10 6 square kilometers - about 0.07% of the total area of the Earth. Incredibly, this is only 20% greater than the area of all human-inhabited areas on our planet!
- The average density of the Moon is 3.4 g/cm 3 . It is 40% less than the density of the Earth - primarily due to the fact that the satellite is devoid of many heavy elements like iron, which our planet is rich in. In addition, 2% of the Moon's mass is regolith - small crumbs of rock created by cosmic erosion and meteorite impacts, the density of which is lower than normal rock. Its thickness in some places reaches tens of meters!
- Everyone knows that the Moon is much smaller than the Earth, which affects its gravity. The acceleration of free fall on it is 1.63 m/s 2 - only 16.5 percent of the entire gravitational force of the Earth. The astronauts' jumps on the Moon were very high, even though their spacesuits weighed 35.4 kilograms - almost like knight's armor! At the same time, they were still holding back: a fall in a vacuum was quite dangerous. Below is a video of the astronaut jumping from the live broadcast.
- Lunar maria cover about 17% of the entire Moon - mainly its visible side, which is covered by almost a third. They are traces of impacts from particularly heavy meteorites, which literally tore the crust off the satellite. In these places, only a thin, half-kilometer layer of solidified lava—basalt—separates the surface from the lunar mantle. Because the concentration of solids increases closer to the center of any large cosmic body, there is more metal in the lunar maria than anywhere else on the Moon.
- The main form of relief of the Moon is craters and other derivatives from impacts and shock waves from steroids. Huge lunar mountains and circuses were built and changed the structure of the surface of the Moon beyond recognition. Their role was especially strong at the beginning of the history of the Moon, when it was still liquid - the falls raised whole waves of molten stone. This also caused the formation of lunar seas: the side facing the Earth was hotter due to the concentration of heavy substances in it, which is why asteroids affected it more strongly than the cool back side. The reason for this uneven distribution of matter was the gravity of the Earth, which was especially strong at the beginning of the Moon’s history, when it was closer.
- In addition to craters, mountains and seas, there are caves and cracks in the moon - surviving witnesses of the times when the bowels of the Moon were as hot as , and volcanoes were active on it. These caves often contain water ice, just like the craters at the poles, which is why they are often considered as sites for future lunar bases.
- The real color of the Moon's surface is very dark, closer to black. All over the Moon there are a variety of colors - from turquoise blue to almost orange. The light gray tint of the Moon from the Earth and in the photographs is due to the high illumination of the Moon by the Sun. Due to its dark color, the surface of the satellite reflects only 12% of all rays falling from our star. If the Moon were brighter, during full moons it would be as bright as day.
How was the Moon formed?
The study of lunar minerals and its history is one of the most difficult disciplines for scientists. The surface of the Moon is open to cosmic rays, and there is nothing to retain heat at the surface - therefore, the satellite heats up to 105 ° C during the day, and cools down to –150 ° C at night. The two-week duration of day and night increases the effect on the surface - and as a result, the minerals of the Moon change beyond recognition with time. However, we managed to find out something.
Today it is believed that the Moon is the product of a collision between a large embryonic planet, Theia, and the Earth, which occurred billions of years ago when our planet was completely molten. Part of the planet that collided with us (and it was the size of ) was absorbed - but its core, along with part of the surface matter of the Earth, was thrown into orbit by inertia, where it remained in the form of the Moon.
This is proven by the deficiency of iron and other metals on the Moon, already mentioned above - by the time Theia tore out a piece of earthly matter, most of the heavy elements of our planet were drawn by gravity inward, to the core. This collision affected the further development of the Earth - it began to rotate faster, and its axis of rotation tilted, which made the change of seasons possible.
Then the Moon developed like an ordinary planet - it formed an iron core, mantle, crust, lithospheric plates and even its own atmosphere. However, the low mass and composition poor in heavy elements led to the fact that the interior of our satellite quickly cooled, and the atmosphere evaporated from the high temperature and lack of a magnetic field. However, some processes inside still occur - due to movements in the lithosphere of the Moon, moonquakes sometimes occur. They represent one of the main dangers for future colonizers of the Moon: their scale reaches 5.5 points on the Richter scale, and they last much longer than those on Earth - there is no ocean capable of absorbing the impulse of the movement of the Earth’s interior.
The main chemical elements on the Moon are silicon, aluminum, calcium and magnesium. The minerals that form these elements are similar to those on Earth and are even found on our planet. However, the main difference between the minerals of the Moon is the absence of exposure to water and oxygen produced by living beings, a high proportion of meteorite impurities and traces of the effects of cosmic radiation. The Earth's ozone layer was formed quite a long time ago, and the atmosphere burns most of the mass of falling meteorites, allowing water and gases to slowly but surely change the appearance of our planet.
Future of the Moon
The Moon is the first cosmic body after Mars that claims priority for human colonization. In a sense, the Moon has already been mastered - the USSR and the USA left state regalia on the satellite, and orbital radio telescopes are hiding behind the far side of the Moon from the Earth, a generator of a lot of interference on the air. However, what does the future hold for our satellite?
The main process, which has already been mentioned more than once in the article, is the moving away of the Moon due to tidal acceleration. It happens quite slowly - the satellite moves away no more than 0.5 centimeters per year. However, something completely different is important here. Moving away from the Earth, the Moon slows down its rotation. Sooner or later, a moment may come when a day on Earth will last as long as a lunar month - 29–30 days.
However, the removal of the Moon will have its limit. After reaching it, the Moon will begin to approach the Earth in turns - and much faster than it was moving away. However, it will not be possible to completely crash into it. 12–20 thousand kilometers from the Earth, its Roche lobe begins - the gravitational limit at which a satellite of a planet can maintain a solid shape. Therefore, the Moon will be torn into millions of small fragments as it approaches. Some of them will fall to Earth, causing a bombardment thousands of times more powerful than nuclear, and the rest will form a ring around the planet like . However, it will not be so bright - the rings of gas giants consist of ice, which is many times brighter than the dark rocks of the Moon - they will not always be visible in the sky. The ring of the Earth will create a problem for astronomers of the future - if, of course, there is anyone left on the planet by that time.
Colonization of the Moon
However, all this will happen in billions of years. Until then, humanity views the Moon as the first potential object for space colonization. However, what exactly is meant by “lunar exploration”? Now we will look at the immediate prospects together.
Many people think of space colonization as similar to New Age colonization of Earth - finding valuable resources, extracting them, and then bringing them back home. However, this does not apply to space - in the next couple of hundred years, delivering a kilogram of gold even from the nearest asteroid will cost more than extracting it from the most complex and dangerous mines. Also, the Moon is unlikely to act as a “dacha sector of the Earth” in the near future - although there are large deposits of valuable resources there, it will be difficult to grow food there.
But our satellite may well become a base for further space exploration in promising directions - for example, Mars. The main problem of astronautics today is restrictions on the weight of spacecraft. To launch, you have to build monstrous structures that require tons of fuel - after all, you need to overcome not only the gravity of the Earth, but also the atmosphere! And if this is an interplanetary ship, then it also needs to be refueled. This seriously constrains designers, forcing them to choose economy over functionality.
The moon is much better suited as a launch pad for spaceships. The lack of an atmosphere and low speed to overcome the Moon's gravity - 2.38 km/s versus 11.2 km/s on Earth - make launches much easier. And the satellite's mineral deposits make it possible to save on the weight of fuel - a stone around the neck of astronautics, which occupies a significant proportion of the mass of any apparatus. If the production of rocket fuel were developed on the Moon, it would be possible to launch large and complex spacecraft assembled from parts delivered from Earth. And assembly on the Moon will be much easier than in low-Earth orbit - and much more reliable.
The technologies existing today make it possible, if not completely, then partially to implement this project. However, any steps in this direction require risk. The investment of huge amounts of money will require research for the necessary minerals, as well as the development, delivery and testing of modules for future lunar bases. And the estimated cost of launching even the initial elements alone can ruin an entire superpower!
Therefore, the colonization of the Moon is not so much the work of scientists and engineers, but of the people of the whole world to achieve such valuable unity. For in the unity of humanity lies the true strength of the Earth.
John Dunford said: "I took this picture on Saturday evening, just after the super moon rose in the south of Spain, near the village of Competa, about 9:30 pm or so."
Here's what photographer Wolfram Schubert said about his Super Moon shot: “This photograph was taken in Erfurt, central Germany. In the foreground is St Mary's Cathedral."
Super Moon is what the Earth's satellite is called when it reaches its closest point to the planet, the so-called perigee. Ryan Gordon documented this phenomenon in the Netherlands.
The fullness of the Moon and its brightness are reflected in this photograph by Hugh McAllister. Image taken in Shrigley, County Down, Northern Ireland.
José Rambo photographed the Super Moon in Tarifa, Spain. During this unusual natural phenomenon, the Moon appears to residents 14% larger and 30% brighter than at its greatest distance from the Earth.
Jimena Velez-Liendo witnessed the moon's perigee as it rose above the clouds in the city of Cochabamba, in central Bolivia.
John Brown from Toronto in Canada was traveling to Padua, Italy and took this photo of the Moon in front of the Abbey of St. Justina while walking in Prato dell Valle.
The Super Moon is visible from the shell in the UK, where Rob Deyes took this photo. He said: "I noticed the moon rising over the rooftops and quickly grabbed my tripod and camera. In total I took about 30 pictures with different exposures and angles. So in some frames the satellite appears even brighter."
Paul Merton observed the Moon's perigee high above the Tuscan city of Lucignano in Italy.
The Super Moon rises above the clouds in this photo by Tim Nuttall. Picture taken in Withernsea, East Yorkshire. Many stargazers in the UK may have been unable to see the Moon's perigee phenomenon due to cloud cover. Those who missed this event in June will be able to enjoy the huge and bright Moon again in August 2014.
It seems like a stupid question and maybe even a school student can answer it. However, the rotation mode of our satellite is not described accurately enough, and moreover, there is a gross error in the calculations - the presence of water ice at its poles is not taken into account. It is worth clarifying this fact, and also remembering that the great Italian astronomer Gian Domenico Cassini was the first to point out the fact of the strange rotation of our natural satellite.
How does the Moon rotate?
It is well known that the Earth’s equator is inclined by 23 ° and 28’ to the ecliptic plane, that is, the plane closest to the Sun, it is this fact that leads to the change of seasons, which is extremely important for life on our planet. We also know that the plane of the Moon’s orbit is inclined at an angle of 5 ° 9’ relative to the plane of the ecliptic. We also know that the Moon always faces the Earth with one side. The action of tidal forces on Earth depends on this. In other words, the Moon rotates around the Earth in the same time it takes to complete a full revolution around its own axis. We thus automatically receive part of the answer to the question indicated in the title: “The Moon rotates around an axis and its period is exactly equal to that of a complete revolution around the Earth.”
However, who knows the direction of rotation of the Moon's axis? This fact is not known to everyone, and moreover, astronomers admit that they made a mistake in the formula for calculating the direction of rotation, and this is due to the fact that the calculations did not take into account the fact of the presence of water ice at the poles of our satellite.
There are craters on the surface of the Moon in close proximity to the poles that never receive sunlight. In those places, it is constantly cold and it is quite possible that in these places reserves of water ice could be stored, delivered to the Moon by comets falling on its surface.
NASA scientists also proved the truth of this hypothesis. This is easy to understand, but another question arises: “Why are there areas that are never illuminated by the Sun? The craters are not deep enough to hide their reserves, provided there is an overall favorable geometry."
Look at the photo of the Moon's south pole:
This image was taken by NASA using the Lunar Reconnaissance Orbiter, a spacecraft in orbit around the Moon that continually takes photographs of the lunar surface to better plan future missions. Each photograph taken at the South Pole over a six-month period was converted into a binary image so that each pixel illuminated by the Sun was assigned a value of 1, while those in the shadow were assigned a value of 0. These photographs were then processed by defining for each pixel percentage of time it was illuminated. As a result of "map illumination", scientists saw that some areas always remain in the shadow, and a few (volcanic ridges or peaks) remain always visible to the Sun. Gray rather than reflect areas that have gone through a period of illumination that is darkened. Really impressive and educational.
Let us return, however, to our question. To achieve this result, namely the constant presence of large areas in complete darkness, it is necessary that the axis of rotation of the Moon be directed to the right in relation to the Sun, in particular, which is practically perpendicular to the ecliptic.
However, the lunar equator is inclined with respect to the ecliptic only 1° 32'. It would seem an insignificant indicator, but it suggests that at the poles of our satellite there is water, which is in a physical state - ice.
This geometric configuration had already been studied and translated into law by the astronomer Gian Domenico Cassini in 1693 in Liguria, during his study of the tides and their influence on the satellite. Regarding the Moon, they sound like this:
1) The period of rotation of the Moon is synchronized with the period of revolution around the Earth.
2) The Moon's rotation axis is maintained at a fixed angle relative to the ecliptic plane.
3) The axes of rotation, the normal to the orbit and the normal to the ecliptic lie in the same plane.
After three centuries, these laws have recently been tested using more modern methods of celestial mechanics, which have confirmed their accuracy.
The science
When the full moon arrives, the moon's bright light captures our attention, but the moon also holds other secrets that may surprise you.
1. There are four types of lunar months
Our months correspond approximately to the period of time that it takes for our natural satellite to go through complete phases.
From excavations, scientists discovered that people since the Paleolithic era have been counting days by linking them with the phases of the Moon. But there are actually four different types of lunar months.
1. Anomalistic- the length of time it takes the Moon to orbit the earth, measured from one perigee (the point of the Moon's orbit closest to the Earth) to the other, which takes 27 days, 13 hours, 18 minutes, 37.4 seconds.
2. Nodal- the length of time it takes the Moon to travel from the point where the orbits intersect and return to it, which takes 27 days, 5 hours, 5 minutes, 35.9 seconds.
3. Sidereal- the length of time it takes the Moon to circle the earth, guided by the stars, which takes 27 days, 7 hours, 43 minutes, 11.5 seconds.
4. Synodic- the length of time it takes the Moon to go around the earth, guided by the Sun (this is the period of time between two successive conjunctions with the Sun - the transition from one new moon to another), which takes 29 days, 12 hours, 44 minutes, 2.7 seconds . The synodic month is used as a basis in many calendars and is used to divide the year.
2. From Earth we see a little more than half of the Moon
Most reference books mention that because the Moon rotates only once during each orbit around the Earth, we never see more than half of its entire surface. In truth, we get to see more during its elliptical orbit, namely 59 percent.
The Moon's rotation speed is the same, but its rotation frequency is not, allowing us to see only the edge of the disk from time to time. In other words, the two movements do not occur in perfect sync, even though they converge towards the end of the month. This effect is called libration by longitude.
Thus, the Moon wobbles in the east and west directions, allowing us to see a little farther in longitude at each edge. We will never see the remaining 41 percent from the Earth, and if someone were on the other side of the Moon, he would never see the Earth.
3. It takes hundreds of thousands of moons to match the brightness of the sun
The Full Moon has an apparent magnitude of -12.7, but the Sun is 14 times brighter, with an apparent magnitude of -26.7. The brightness ratio of the Sun and Moon is 398.110 to 1. It will take so many moons to match the brightness of the sun. But this is all a moot point, since there is no way to fit so many moons in the sky.
The sky is 360 degrees, including the half beyond the horizon that we can't see, so there are more than 41,200 square degrees in the sky. The moon is only half a degree across, giving an area of 0.2 square degrees. So you could fill the entire sky, including the half beneath our feet, with 206,264 full Moons and still have 191,836 left to match the brightness of the Sun.
4. The first and last quarter of the Moon are not half as bright as the Full Moon.
If the surface of the Moon were like a completely smooth billiard ball, then the brightness of its surface would be the same everywhere. In this case, it would be twice as bright.
But The moon has a very uneven terrain, especially near the border of light and shadow. The landscape of the Moon is pierced by countless shadows from mountains, boulders and even the smallest particles of lunar dust. In addition, the surface of the Moon is covered with dark areas. Ultimately, in the first quarter, the Moon 11 times less bright than when full. The Moon is actually slightly brighter in the first quarter than in the last quarter because some parts of the moon reflect light better during this phase than in other phases.
5. 95 percent of the illuminated Moon is half as bright as the full Moon
Believe it or not, about 2.4 days before and after the full moon, the Moon shines half as brightly as the full Moon. Even though 95 percent of the Moon is illuminated at this time and will appear to most normal observers to be full, it is about 0.7 magnitudes less bright than at full, making it half as bright.
6. When viewed from the Moon, the Earth also goes through phases
However, these phases opposite to lunar phases that we see from Earth. When we see the new moon, we can see the full Earth from the Moon. When the Moon is in the first quarter, then the Earth is in the last quarter, and when the Moon is between the second quarter and the full moon, then the Earth is visible in the form of a crescent, and finally, the Earth in a new phase is visible when we see the full moon.
From any point on the Moon (except for the farthest side, where Earth cannot be seen), the Earth is in the same place in the sky.
From the Moon, the Earth appears four times larger than the full Moon When we observe it, and depending on the state of the atmosphere, it shines from 45 to 100 times brighter than the full Moon. When the full Earth is visible in the lunar sky, it illuminates the surrounding lunar landscape with a bluish-gray light.
7. Eclipses also change when viewed from the Moon.
Not only do the phases change places when viewed from the Moon, but also lunar eclipses are solar eclipses when viewed from the Moon. In this case, the Earth's disk covers the Sun.
If it completely covers the Sun, a narrow strip of light surrounds the dark disk of the Earth, which is illuminated by the Sun. This ring has a reddish tint, as it is due to the combination of light from sunrises and sunsets that occur at this moment. This is why during a total lunar eclipse, the Moon takes on a reddish or copper hue.
When a total eclipse of the Sun occurs on Earth, an observer on the Moon may see for two or three hours a small, distinct dark spot move slowly across the Earth's surface. This dark shadow of the Moon that falls on Earth is called umbra. But unlike a lunar eclipse, where the Moon is completely engulfed by the Earth's shadow, the lunar shadow is several hundred kilometers smaller when it touches the Earth, appearing only as a dark spot.
8. Craters of the Moon are named according to certain rules
Lunar craters were formed by asteroids and comets that collided with the Moon. It is believed that only on the near side of the Moon approximately 300,000 craters, more than 1 km wide.
Craters named after scientists and explorers. For example, Copernicus Crater was named after Nicolaus Copernicus, a Polish astronomer who, in the 1500s, discovered that the planets move around the sun. Archimedes Crater named after a mathematician Archimedes, who made many mathematical discoveries in the 3rd century BC.
Tradition assign personal names to lunar formations started in 1645 Michael van Langren(Michael van Langren ) , a Brussels engineer who named the main features of the Moon after kings and great men on Earth. On his lunar map he named the largest lunar plain ( Oceanus Procellarum) in honor of its patron Spanish Philip IV.
But just six years later, Giovanni Batista Riccoli( Giovanni Battista Riccioli ) from Bologna created his own lunar map, removing the names he gave van Langren and instead assigned the names of mostly famous astronomers. His map became the basis of a system that survives to this day. In 1939, British Astronomical Association released a catalog of officially named lunar formations. " Who's Who on the Moon", indicating the names of all entities accepted International Astronomical Union(MAS).
To date MAS continues to decide what names to give to craters on the Moon, along with names for all astronomical objects. MAS organizes the naming of each specific celestial body around a specific theme.
The names of craters today can be divided into several groups. As a rule, the craters of the Moon were called in honor of deceased scientists, scientists and researchers, who have already become renowned for their contributions in their respective fields. So craters around the crater Apollo And Seas of Moscow on the Moon will be named after American astronauts and Russian cosmonauts.
9. The Moon has a huge temperature range
If you start searching the Internet for data on the temperature on the Moon, you will most likely get confused. According to the data NASA, temperatures at the Moon's equator range from very low (-173 degrees Celsius at night) to very high (127 degrees Celsius during the day). In some deep craters near the poles of the Moon, the temperature is always around -240 degrees Celsius.
During a lunar eclipse, when the Moon moves toward Earth's shadow in just 90 minutes, surface temperatures can drop by 300 degrees Celsius.
10. The moon has its own time zones
It is quite possible to tell the time on the Moon. In fact, in 1970 the company Helbros Watches(Helbros Watches) asked Kenneth L. Franklin ( Kenneth L. Franklin )
, who for many years was the chief astronomer at New York Hayden Planetarium create watches for astronauts who set foot on the Moon. These clocks measured time in so-called " Lunations" is the time it takes for the Moon to orbit the Earth. Each Lunation corresponds to 29.530589 days on Earth.
For the Moon, Franklin developed a system called lunar time. He imagined local lunar time zones following standard time zones on Earth, but based on meridians that were 12 degrees wide. They will be called simply " 36 degrees Eastern Standard Time" etc., but it is possible that other more memorable names will be adapted, such as " Copernican time", or " time of Western calm".