At present, the Earth has only one natural satellite- Moon. But relatively recently - some 6-7 thousand years ago - two moons could be seen above our planet. This is evidenced not only by the myths and traditions of many peoples, but also by geological finds. Blocks of pure iron In the north of Argentina is the area of Campo del Cielo (in translation - "heavenly field"). This name is taken from an ancient Indian legend, which tells about the fall from the sky at this place of mysterious metal blocks. Pieces of iron, according to old Spanish chronicles, were found here as early as the 16th century. The conquistadors used them to make swords and spears. Particularly lucky was a certain Herman de Miraval, who in 1576, in a rather remote area, among marshy lowlands, stumbled upon a huge block of pure iron. The enterprising Spaniard visited her several times and beat off pieces from her for various needs. In 1783, the prefect of one of the provinces, Don Rubin de Celis, organized an expedition to this block and, having discovered it after a long search, estimated its mass at about 15 tons. Detailed Description the object has not been preserved, and since then no one has seen it, although attempts to find the block have been made more than once. In 1803, a meteorite weighing about a ton was discovered in the vicinity of Campo del Cielo. Its largest fragment (635 kg) was delivered to Buenos Aires in 1813. It was later acquired by the Englishman Sir Woodbine Darish and donated to the British Museum. This block of space iron is still resting on a pedestal in front of the entrance to the museum. Part of its surface is specially polished to show the structure of the metal with the so-called "Widmanstetten figures", which speak of the extraterrestrial origin of the object.
In Campo del Cielo and its environs, iron fragments are still found weighing from a few kilograms of grams to many tons. The largest weighed 33.4 tons. It was found in 1980 near the town of Gancedo American meteorite researcher Robert Hug tried to buy it and take it to the United States, but the Argentine authorities opposed this. To date, this meteorite is considered the second largest among all those found on Earth - after the so-called Hoba meteorite, weighing about 60 tons. rain". Evidence of this, in addition to the finds of the iron objects themselves, is a large number of craters in the Campo del Cielo region. The largest of them is the Laguna Negra crater with a diameter of 115 meters and a depth of more than 5 meters.
Huge meteorite exploded in the atmosphere
In 1961, the professor of Columbia University (USA), the world's largest specialist in meteorite W. Cassidy, became interested in the finds in Campo del Cielo. The expedition organized by him discovered a large number of small metal meteorites - hexaderites, consisting of almost chemically pure iron (96% of it, the rest is nickel, cobalt and phosphorus). The study of other meteorites found at different times in this area gives the same composition. According to the scientist, this proves that they are all fragments of a single celestial body. Cassidy also drew attention to a strange fact: usually, when a large meteorite explodes in the atmosphere, its fragments fall to the Earth, scattering in an ellipse with a maximum diameter of about 1600 meters. And on Campo del Cielo, the length of this diameter is 17 kilometers!
The published preliminary findings of Cassidy's research have generated worldwide interest. Hundreds of volunteers joined the scientist, and as a result, new fragments of meteoric iron were discovered even at a considerable distance from Campo del Cielo, up to the Pacific coast.
Satellite "two"
But it turned out that the territory of the finds is even more extensive. An unexpected light on the history of the Campo del Cielo meteorite was shed by a discovery from Australia. Here back in 1937, 300 kilometers from the town of Hanbury. in an ancient crater with a diameter of 175 meters and a depth of about 8 meters, an iron meteorite weighing 82 kilograms and several fragments of a smaller weight were found. In 1969, they conducted a study of their composition and found that all these fragments are almost identical to the iron meteorites from Campo del Cielo.
Craters in the Hanbury area have been known since the 1920s. There are several dozen of them, the largest of them reaches 200 meters, but most are relatively small - from 9 to 18 meters. During the excavations carried out here since the 1930s, over 800 fragments of meteoric iron were found in the craters, including four parts of one piece with a total weight of about 200 kilograms.
The final conclusion that Cassidy came to was this: a huge meteorite fell to Earth, but not suddenly. For some time before its fall, this celestial body revolved around the Earth in an elliptical orbit, gradually approaching the planet. Being in orbit could last quite a long time - a thousand years or more. However, under the influence of the force of gravity, this second Moon eventually approached the Earth so much that it crossed the so-called Rocher boundary, after which it entered the atmosphere and broke up into fragments of various sizes, which fell to the surface of the planet.
The approximate date of the disaster was determined by radiocarbon analysis - it turned out about 5800 years ago. Thus, the catastrophe occurred already in the memory of mankind, in the 4th millennium BC. e., when the civilizations of antiquity began to emerge, leaving behind monuments of writing. In them we find mythologized references to the second natural satellite of the planet and the catastrophe caused by its fall. For example, on the clay tablets of Sumer, the goddess Innana is described, crossing the sky and emitting a frightening radiance. An echo of the same events is, apparently, the ancient Greek myth of Phaethon.
The luminous celestial body is mentioned by Babylonian, Egyptian, Old Norse sources, myths of the peoples of Oceania. The English ethnologist J. Fraser notes that out of 130 Indian tribes of Central and South America there is not one in whose myths this theme would not be reflected.
“There is nothing surprising in all this,” writes the American astronomer M. Papper, “after all, metal meteorites are very clearly visible in flight. Reflecting sunlight, they sparkle much brighter than stone meteorites; as for a large fireball made of pure iron, its luminosity in the night sky should have exceeded the luminosity of the Moon in its brightness.
The elliptical orbit, along which the fireball moved, assumed that at certain periods the passage of this object was close to the Earth. At the same time, the fireball came into contact with the upper layers of the atmosphere and became so hot that its brilliance should have been visible even in daylight. As the object approached our planet, its luminosity increased, causing panic among the population. According to M. Papper, the orbit that made the fireball then heat up when in contact with the earth's atmosphere, then, moving away from it, freeze again in the icy cold of space, and led to the destruction of it into pieces. Judging by the rather large area on which the fragments scattered - from South America to Australia - the fireball broke up while still in orbit and entered the Earth's atmosphere in the form of a string of separate fragments. The fireball could have caused the Flood
The largest pieces, according to experts, fell into the Pacific Ocean, causing unprecedented waves that could bypass the Earth. In the legends of the Indians of the Amazon basin, it is said that stars fell from heaven, a terrible roar and roar was heard, and everything plunged into darkness, and then a downpour fell on the earth, which flooded the whole world. “The water rose to a great height,” says one of the Brazilian legends, “and the whole earth was submerged in water. The darkness and the rain didn't stop. People fled, not knowing where to hide; climbed the highest trees and mountains." The Brazilian legend is echoed by the fifth book of the Mayan code “Chilam Balam”: “The stars fell from heaven, crossed the firmament with a fiery plume, the earth was covered with ashes, rumbled, trembled and cracked, shaking with tremors. The world was falling apart."
All these legends are about a catastrophe accompanied by earthquakes, volcanic eruptions and floods. Its epicenter was clearly in the Southern Hemisphere, since the nature of myths changes as you move north. Traditions tell only about a strong flood. It was this event that apparently remained in the memory of the Sumerians and Babylonians and found its most vivid embodiment in the well-known biblical myth of the Flood.
The science
Scientists have found that our planet once had two moons. Smaller in size the moon's twin only lasted a few million years, and then collided with our satellite, which we still have the opportunity to observe.
This theory was put forward at a conference on the Moon by Prof. Eric Asfaug(Erik Asphaug) from the University of California, Santa Cruz.
Most of our planets solar system, with the exception of the Earth there are several satellites. So Mars has 2, Jupiter has 66, Saturn has 62, Uranus has 27, and Neptune has 13.
Scientists still don't know why does the earth have only one natural satellite- Moon. But maybe there used to be more of them?
The Moon is the Earth's satellite
According to the theory, the second moon revolved around the Earth at the same speed and distance, and it was slightly sucked until it collided with the other, connecting into a single whole.
The tidal forces and gravity of the Sun most likely led to the instability of the Moon's orbit, which led to the collision. This may explain the asymmetry of the lunar crust, since the surface of the moon facing the earth is low and flat, and back side covered with craters and mountains.
The diagram shows the four stages of the collision of two moons about 4 billion years ago
Professor Asfaug believes that the moon's mountainous landscape is the remnants of a smaller satellite after a merger. It is assumed that the size of the twin was about one-thirtieth the size of today's moon.
The Earth and Moon formed between 30 and 130 million years after the birth of our solar system, which happened 4.6 billion years ago.
Last year, Harvard scientists theorized that the Moon was once part of the Earth that broke away after colliding with another celestial body.
Astronomers have recently found three more planets like earth orbiting a single star that could possibly support life.
Researchers believe there could be up to 100 billion Earth-like planets in our galaxy.
Rotation of the Moon around the Earth
The moon revolves around the earth in 27.3 days. The Moon's orbit averages 385,000 km from Earth.
Like other planets in the solar system, the moon's orbit is not round but elliptical.
At its closest point, called perigee, the Moon is 364,397 km from Earth. At the farthest point, called the apogee, it is 406,731 km from our planet. When the Moon is full and closest to the Earth, it is visible more and brighter.
On September 9, 2018, not all people in the world, but, most likely, very many, followed the live broadcast of the passage of the asteroid 2018 RC by the Earth, which passed from us at a record close distance of 1/2 the distance to the Moon.
The asteroid did not fall into the Atlantic and seemed to fly further, assuring the audience of a stable tomorrow. However, in reality, as one lady told her twin sister's husband, sometimes things are not what they seem.
In 2016, NASA miraculously discovered one small asteroid, named 2016 HO3. This is a small space pebble, the size of which is 35 X 90 meters, that is, the 2016 HO3 asteroid is almost a complete analogue of the 2018 RC asteroid.
On the NASA website you can see how 2016 HO3 runs in orbit. As you can see (if you click the button in the upper right corner) - its trajectory differs little from the trajectory of 2018 RC
However, NASA somehow made another animation of the asteroid 2016 HO3. There, the movement is absolutely the same, but only the trajectory of the asteroid is shown as a continuous line:
As this animation clearly demonstrates, the asteroid 2016 HO3 is for the Earth something like a quasi-moon, that is, like a satellite. This was not always the case, and according to NASA calculations, the Earth dragged 2016 HO3 into this cycle when it flew by at a distance of 100 distances from the Moon. Since then, it will fly like this, as close as possible to the Earth at 38 lunar distances, and moving away from the Earth by no more than 100 distances to the Moon.
And what was the distance to the asteroid 2018 RC at the time of September 9, 2018? And there was only half the lunar distance! In other words, if even at 100 distances to the Moon (40,000,000 km) the Earth dragged an asteroid into its orbit, then what are the chances of quietly flying past the asteroid at a distance 200 times less? None.
At the moment of closest approach to the Earth on September 9, the speed of 2018 RC relative to the Earth was zero by space standards - both bodies flew on almost parallel courses with almost identical speeds of about 30 kilometers per second. Therefore, there is now no doubt that the orbit of 2018 RC has changed and become similar to the orbit of 2016 HO3. That is, it will still circle around the Sun, simultaneously making loops around the Earth.
However, since 2018 RC was 200 times closer to the Earth than 2016 HO3 at the time of the capture by gravity of our planet, the asteroid will no longer circle forever, and sooner or later it will fall, this is inevitable. Perhaps this fall will drag on for several years, perhaps for several months or even weeks. Only NASA knows the truth about the new 2018 RC trajectory, but this truth will be revealed to the public only at the very last moment. Or, more likely, never at all.
The moon is a familiar part of the night landscape. She lights the way for couples in love, controls the ebb and flow, and causes werewolves to appear in horror films. But what if our planet had two satellites? Scientists say: no good.
Take two
Let's start with the fact that our Moon was formed 4.5 billion years ago when a huge asteroid the size of Mars flew into the Earth. The debris from the impact flew into orbit and after some time turned into the familiar Moon. And people were very lucky that at that time they were not yet on the planet.
A second moon would also bring a lot of trouble. Firstly, in order for it to appear, a good block from space is also needed. But even if we skip the period of formation of the second satellite and go to the moment when two moons appear in the Earth's sky at once, there is little positive.
The new moon's gravitational pull would create tides eight times our current ones, with huge tidal waves larger than anything we've ever seen. This will lead to earthquakes and more volcanic activity that will continue for many years and eventually lead to the mass extinction of marine life, which will affect the overall ecological situation. In addition, coastal cities will cease to exist from destructive waves: New York, San Francisco, Sydney, St. Petersburg.
Lots of water and light
When the situation more or less improves, life on Earth will be completely different. At night it will be much brighter than during the day, thanks to the reflected light of two satellites at once. And the darkness of the night "at least gouge out your eye" will be much less common.
True, some researchers are sure that the Earth already has two or even more satellites. The fact is that the planet "picks up" small asteroids that fly by, and they begin to rotate in the earth's orbit for several weeks or months before they again go to space trip.
Of course, such babies are unlikely to seriously affect what is happening on Earth. But such "colleagues" of the Moon are better than a full-fledged brother who is able to turn our lives around.
(That's right - in plural) have occupied scholars for centuries. Astronomers of the 19th and first half of the 20th centuries tried to find companions of the Moon. However, time after time, their assumptions and even convincing evidence turned out to be erroneous. Today, everyone from school knows that the only natural satellite of the Earth is the cosmic body of the Moon. Many other candidates are also of interest to astronomers, as they are not fictitious, but real-life objects that were mistakenly assigned the status of a permanent satellite of our planet.
fireball
Many people who are interested in studying celestial bodies, French astronomer Frederic Petit is well known. He was director of the Toulouse Observatory in the middle of the 19th century. Today, Petit is best known as a supporter of the theory that the Moon is not the only natural satellite of the Earth, but one of several. According to the astronomer, fireballs (large and fairly bright meteors) were suitable for the role of her companions. Candidates for satellites circled the planet in an elliptical orbit. The most famous is the fireball that Petit observed in 1846. Summarizing the data - his own and other scientists - about the object, the astronomer concluded that the body rotates with a period of 2 hours 45 minutes, with perigee at a distance of 11.4 km and apogee at 3570 km.
Despite the fact that Frederic Petit's measurements and calculations were confirmed by some astronomers, his assumption was soon refuted. In 1851, Urbain Le Verrier provided evidence that the theory of the Toulouse scientist was wrong.
New Assumptions
Petit was not the only astronomer who tried to refute the conventional wisdom about how many natural satellites the Earth has. His colleague in this matter was a scientist from Hamburg, Dr. Georg Waltemat. In 1898, he announced the discovery of a system of small satellites. One of them, according to the calculations of the scientist, was located at a distance of just over a million kilometers from the Earth and made one revolution in 119 days. The diameter of the hypothetical satellite was 700 km.
Waltemath expected that the second moon would pass across the solar disk in February 1898, and this would be proof of the correctness of the researcher. The satellite was indeed spotted by amateur astronomers in Germany. However, none of the professionals observing the Sun that day noticed anything of the sort.
Another try
Waltemat did not leave his search. In July of that year, he wrote an article about another candidate for the role of a lunar companion. with a diameter of 746 km circulated, according to the calculations of the author of the theory, at a distance slightly exceeding 400 thousand kilometers from our planet. However, these data also have not been confirmed. Hypothetical natural satellites of the Valtematha Earth could not get the status of real-life objects.
Mystic
A feature of the satellite, "discovered" by Valtemat, was the impossibility of observing it at any other moments, except for the time of passage through the solar disk. The object practically did not reflect light, and therefore was hardly noticeable. In 1918, astrologer Walter Gornold announced the rediscovery of the moon Valtemath. He confirmed his "dark" nature and named Lilith (that, according to Kabbalah, was the name of Adam's first wife). The astrologer insisted that the second moon was comparable in mass to the first.
In the scientific world, these statements caused only a smile. Such a massive body would not go unnoticed, since its presence would have a significant impact on the Moon, which would be reflected in its movement.
Politics
The natural satellite of the Earth (Moon) or Mars and Venus, its closest neighbors, have always been associated with some secrets in the minds of people. In the past century, these space objects were often thought of as dwellings alien civilizations or military bases of unfriendly states. Against the background of such assumptions, the hypotheses about artificial satellites launched into orbit in an atmosphere of strict secrecy seemed more real.
In the middle of the last century, there were rumors about two similar objects. After some time, reports began to appear in the media about their natural origin. The excitement around new satellites died down in 1959, when astronomer Clyde Tombaugh (the scientist who discovered Pluto), after a long study of the space around the Earth, announced the absence of any objects brighter than 12-14 magnitudes.
Monitoring of near-Earth space
Nowadays, few people do not know what the natural Earth is called. The moon today is recognized as the one and only. However, astronomers constantly monitor outer space in the vicinity of our planet. The purpose of such a study is not to search for new satellites, but to protect against possible collisions, predict them, and ensure the safety of the stations. Clyde Tombaugh was just one of the first to undertake such a study.
Today, the search for cosmic bodies in near-Earth space is the goal of several large projects at once. So far, new natural satellites of the Earth have not been discovered in the process of research.
Quasi-satellites
Of course, the Moon is not the only object in the vicinity of our planet. Research recent years put a lot of information of this kind. There are asteroids that are in 1:1 orbital resonance with the Earth. In the media and popular science literature, they are often referred to as "second moons". The main difference between such objects is the fact that they do not revolve around the Earth, but around the Sun.
A good example of such a cosmic body is the asteroid (3753) Cruitney. It crosses Venus and Mars while moving. The asteroid's orbit is highly elongated, but, unfortunately, it never comes close enough to our planet to be visible through weak equipment. Cruitney can only be seen with a sufficiently powerful telescope.
Trojans
There is another group of objects that are sometimes referred to as natural satellites of the Earth, but they are not. These are the so-called Trojans - asteroids moving in the same orbit as our planet, but ahead or catching up with it. To date, only one such body has been confirmed to exist. This is asteroid 2010 TK7. It is ahead of the Earth by 60º. 2010 TK7 is a small (300 m in diameter) and rather dim object. Its discovery increased the interest of scientists in the search for Trojans in the vicinity of the Earth.
optical effect
The question “how many natural satellites does the Earth have” sometimes, although extremely rarely, arises simply when looking at the night sky. Under a certain set of circumstances, the simultaneous presence of several factors above your head, you can observe a phenomenon called a false moon. To do this, a full (or almost full) night star must be bright enough. A halo appears around him. Lunar rays are refracted in ice crystals of cirrostratus clouds and bright luminous points are formed on both sides of the satellite. An inexperienced observer for some moments may believe that where the natural satellite of the Earth (the Moon) or Mars and other planets plow space, new real-life space objects have appeared. However, the illusion quickly dissipates. The false moon, or parselena, is more like a play of light than it really is.
Dual system
The moon is like the closest space object to Earth, is always at the center of many research projects. Of course, not everything is known about her. A lot of controversy is still, for example, caused by the theory of origin. However, it can be safely called one of the most studied objects in space, as well as a marker, a hallmark of our home in the universe. The latter fact is well illustrated by one of the variants of the flag of our planet, which depicts a natural satellite of the Earth.
The most interesting thing is that in the light of relatively recent studies, the status of the Moon is not so unambiguous. According to astronomers, the two most studied objects are a double planet. The natural satellite of the Earth and our space house revolve around the same center of mass. It is located not in the center of the Earth, but at a distance of almost 5 thousand kilometers from it. Quite impressive (and their ratio with the size of the Earth) in comparison with other satellites also speak in favor of such a hypothesis. An example of a similar system is Pluto and Charon, rotating around the same center of mass and always turned the same side to each other.
So, today it is clear to everyone what the name of the natural satellite of the Earth is and that it is the only one. The search for his companions left a noticeable mark in the history of astronomy and confirmed the well-known fact: a person is always not enough with what he has. However, it was thanks to this feature that many discoveries of the last century occurred.
