...At night it illuminates the earth!” It's all about her, about the Moon, which hid the Sun for short but memorable minutes. Indeed, many people poured out onto the streets of the city to admire this rare celestial phenomenon. Several hundred people gathered on Lenin Square, mostly young people and children riding skateboards and bikes. The sun was half hidden in the moon's shadow, and suddenly it became noticeably colder. And a strange twilight slowly set in: it didn’t seem like evening, but the light had noticeably dimmed... And the sounds were muffled, and everything around became unreal, not as always. And what was left of the sun was a tiny horn, a kind of strongly “bitten” crescent.
The people armed themselves as best they could: someone looked at the eclipse through exposed film, through “welding” glasses (we even saw a welding mask: cumbersome, but spectacular). The natural color of the remnant of the solar disk was given by compact discs folded in half. The sun horn looked blood red through the floppy disk window. But the people were especially amused by the doctors from the nearest clinic: they poured out into the street and used X-rays for viewing! And they looked at the sun, and examined the fractures properly: two in one! And there were those who hastily smoked the glass of their own glasses with gasoline lighters and matches. And everyone was occupied with one question: “Will it hide it completely or not? So what, what did they write about incomplete? What if completely?..”
The action was short-lived, about half an hour. And when the eclipse reached its maximum, the Moon seemed to spin in place, revealing top part edges of the Sun, then the lower one. Here the horn hangs with its ends down, now it has turned, and now it has become like the usual crescent. And that’s it, the moon’s shadow went its way, the sun began to slowly free itself from the shadow. And everything returned: warmth, light, conversations became louder, they started working Cell Phones, which suddenly failed.
The sun has returned.
Photo by Yuri Rubinsky.
SUKHUM, December 13 – Sputnik. The most beautiful starfall in the northern hemisphere of the Earth - the Geminids - will outshine the light on the night of December 14 full moon(Supermoon), says the Moscow Planetarium.
Every year, from December 4 to 17, one of the richest and most beautiful meteor showers in the northern hemisphere of the Earth - the Geminids - is observed in the night sky. This phenomenon occurs because planet Earth in December passes through a swarm of small particles thrown into space by the asteroid Phaeton. The stream does not fly towards the Earth, but catches up with it, therefore the speed of the meteors is low - about 35 km/s. At the peak of Geminid activity, up to hundreds of meteors can be observed per hour.
“The maximum activity of the Geminids occurs on December 14, 2016 at 3.00 Moscow time, a fall of up to 120 meteors per hour is expected. But the Moon that night will be at perigee (at its closest distance from the Earth) and at 3.06 Moscow time will enter the full moon phase - the third will occur is the supermoon of the year, and this will make observing meteors very unfavorable. The light of the full Moon will be so bright that it will almost completely eclipse the “starfall”. Provided that the weather is cloudless, only the brightest meteors will be visible. The Geminids are not very fast, bright and practically trailing meteors white", the message says.
Unlike most other meteor showers, the Geminids' progenitor is not a comet, but an object discovered in 1983 using an infrared space telescope and named 3200 Phaethon.
It is not a comet, as it has neither a coma nor a tail. Astronomers classify it as an intermediate object, which is a cross between asteroids and comets. Phaeton's orbit is very elongated, which allows it, during its movement around the Sun, to cross the orbits of all four terrestrial planets from Mercury to Mars. Interestingly, at the same time, it comes closer to the Sun than any other known asteroid (the record belongs to asteroid 2006 HY51), which is why it was named after the hero of the Greek myth about Phaeton, the son of the Sun god Helios.
Every 1.5 years, Phaeton approaches the Sun at a distance that is more than twice the perihelion of the planet Mercury, while the speed of Phaeton near the Sun can reach almost 200 km/s (720,000 km/h). Studies of the meteor shower have shown that its meteor particles are about 1000 years old. That is, if Phaethon was a comet, then over 1000 years it made many revolutions around the Sun, as a result of which all the ice from its core evaporated, and the comet’s tail was gone, only a stone skeleton remained from the core.
The Geminids got their name from the name of the constellation Gemini, in which the radiant of the shower is located (the area where meteors are released). The Geminid radiant is located near the bright star Castor. The meteor shower in the constellation Gemini was discovered at the end of the 20th century. The Geminids are a beautiful giant meteor shower, surpassing all other meteor showers in the number of shooting stars, including the August Perseids.
On the morning of November 13, Jupiter passed next to Venus at a distance of less than half a degree, in astronomy this phenomenon is called a conjunction. The gas giant could be observed on the southeastern horizon since November 12. The planet appeared above the horizon just behind Venus.
Meanwhile, the media again began to scare readers with the “end of the world”, and in the literal sense - according to their version, the rapprochement of Venus and Jupiter will lead to an explosion on the Sun and a temporary darkening on Earth.
The Earth will remain in darkness, as promised, from two weeks to a month - depending on the imagination of the author of the news. Darkness is expected on November 15th.
The source of information, as Gazeta.Ru found out, was the yellow publication Daily Star, which specializes in news in the spirit of “Scientists have found Noah’s Ark” and photographs of celebrities in swimsuits. Moreover, the Daily Star is not trying to make a sensation out of the supposedly impending explosion, but from the very first lines calls the news a “fictitious online theory” invented by “conspiracy theorists.”
The story about an explosion on the Sun caused by the rapprochement of Jupiter and Venus has been wandering from one media to another for several years now. In 2016, the Daily Star already reported, citing the Dinos Mark portal, that “according to NASA... Venus will pass southwest of Jupiter, making it shine 10 times brighter than Jupiter. The light from Venus will heat the gases on Jupiter, causing a chemical reaction."
Dinos Mark refer to the words of Charles Bolden, who at that time served as head of NASA. He allegedly compiled a 1,000-page report explaining what was happening to the US presidential administration, according to which the temperature of the Sun would increase to 9,000 K, which would cause the release of heat from the core of the star.
The reaction will supposedly cause the release of a huge amount of hydrogen, which will provoke powerful explosion in the sun. After this explosion, the Sun will dim and take on a bluish tint, but will return to normal within a few weeks.
At the same time, in 2016, Daily Star journalists turned out to be extremely honest: they called reports about the coming darkness “rumors” and noted that NASA had denied this information.
The impending explosion was allegedly announced at a conference with the presidential administration. Bolden is also credited with saying that the temperature on Earth would rise during this period.
However, this message is not original - the possible “blackout” was discussed back in 2015 at the suggestion of an American tabloid. Then Gazeta.Ru already dealt with this “duck”.
“Venus shines with reflected light, not on its own. It's a planet, not a star. A megaexplosion on the Sun is possible only if the mass of the star increases by a third, astrophysicist and employee of the Moscow Planetarium Alexander Perkhnyak explained to Gazeta.Ru. - Now the temperature on the surface of the Sun is about 6000 degrees Kelvin. According to the spectral classification, it is a yellow star. When the temperature on the surface of the star increases to 10,000 K, the Sun will become a white star. And only when the heating of the surface increases to 60,000 K will it become blue, i.e. such will be its true and visible color.
At the same time, Perkhnyak also noted that any catastrophes that could hypothetically occur on Venus on such a scale that their consequences would affect distant Jupiter would be so detrimental to the Earth neighboring Venus that the inhabitants of our planet would no longer have to worry about anything.
On November 14, 2017, Jupiter will rise before Venus, at 6:40 am. Then every day it will rise higher and higher above the horizon. On November 17 at 7:00, astronomy lovers will be able to admire the beautiful trio - the Moon will pass only 4° north of Jupiter and Venus.
This is not the first time Bolden has become a victim of online pranksters. This year, he was already credited with saying at a press conference in Houston that there are tens of thousands of civilizations in the Universe, alien satellites have captured the Earth’s orbit, and in the coming months people should expect alien invasion. After this statement, Bolden was allegedly escorted off stage by NASA employees, and he was subsequently placed on six-month leave for health reasons.
Despite the fact that Bolden does not deny the possibility of the existence of extraterrestrial civilizations, he, of course, did not make such statements. Moreover, he left his post as head of NASA back in January 2017, so there was no way he could have been sent on leave from his post.
It's rapidly approaching us huge comet, which promises to be the brightest in the history of observations and will eclipse the Moon. Recently discovered by two amateur astronomers, the comet will put on an unprecedented celestial show starting on November 28, 2013, when the celestial body will pass less than two million kilometers from the Sun - very close in astronomical terms.
If forecasts come true, the comet will become one of the largest in human history and will surpass in brightness such celestial bodies as Comet Hale-Bopp of 1997 and Pan-STARRS (C/2011 L4), which will be visible in the sky in March 2013.
The new comet, named C/2012 S1 (ISON), was discovered by the International Optical Science Network in Russia on September 21, when astronomers Vitaly Nevsky (Petrozavodsk, Russia) and Artem Novichonok from Belarus imaged it using an amateur 0.4-meter reflector. Then professional astronomers joined in observing the unusual celestial body. It was they who noticed that in behavior and external signs The comet has much in common with the so-called Great Comet, which flew near the Earth in 1680.
ISON's nearly parabolic orbit indicates it came from the Oort Cloud, a vast region of icy objects orbiting the Sun, an untouched remnant of the solar system's formation. Astronomers believe that there are countless of them there. The comet is currently located in the northwestern corner of the constellation Cancer. At magnitude +18, it is now too dim to be seen with the naked eye. At the same time, the thrifty comet has already acquired a tail, noticeable for astronomical observations. As it approaches the Sun, the core of the celestial guest will heat up, and one day it will be able to be observed even in the Northern Hemisphere without any optical equipment. The unusually bright spectacle will last at least two months, astronomers believe. The comet will fly past the Earth at the end of December 2013 - beginning of January 2014. The question naturally arises: is such close proximity dangerous for the inhabitants of the Blue Planet?
It will be interesting
“The minimum distance to it will be 0.42 astronomical units - that’s almost 62 million kilometers,” says Yuri Zaitsev, senior Researcher Institute of Space Research RAS. “Less than half the distance from Earth to the Sun, but far enough away to avoid any risk of collision.” However, not all astronomers are confident that comet C/2012 S1 (ISON) will survive. It is possible that on approaching the Sun it will collapse, just as comet Elenin (C/2010 X1), discovered by Leonid Elenin in 2010, collapsed last August.
“For now, we can only guess how things will unfold,” said Carl Bettams, a spokesman for the NASA-backed Sungrazer Comet Project. And comet researcher John Bortle, who was the first to notice that the trajectory of the new comet suspiciously exactly coincides with that of the so-called Great (or Great) Comet of 1680, suggests that the current and previous comets were once one whole - a comet of Cyclopean sizes .
The Great Comet of 1680 is quite remarkable. It became the first comet discovered by the German astronomer Gottfried Kirsch using an astronomical instrument - a telescope. With its brightness and especially its unusually long tail, it amazed contemporaries; it was captured by artists and, in particular, by the famous marine painter Love Pieters Verschuer. Scientists believe that it was the first of the recorded comets of the Kreutz family - in this case, it should be periodic, in other words, it should appear from time to time near the Sun. The periodicity of comets can vary - from several tens (like Halley's comet) to several thousand years.
Ice wonder
In order to clarify the nature of comets, there are many hypotheses - from completely scientific to fantastic. The founder of scientific ideas about comets was Edmund Halley, who calculated and published the orbits of 24 comets in 1705 and drew attention to the similarity of the parameters of some of them. From ancient times to the present day, about 2000 comets have been noticed and described. It turned out that most comets move in ellipses, moderately or strongly elongated. When approaching the Sun, the comet forms a tail consisting of gas and dust, and coma, which means not at all life-threatening state, but a nebulous shell surrounding the cometary nucleus. Streams sun rays knocks gas particles out of the coma and throws them back, pulling them into a long smoky tail that moves behind her in space.
The theory of comet tails and shapes was developed in late XIX century Russian astronomer Fyodor Bredikhin (1831-1904). He also belongs to the classification of comet tails, which is used in modern astronomy. Astronomers gained a comprehensive understanding of comets thanks to successful “visits” to Halley’s Comet in 1986 spacecraft"Vega-1" and "Vega-2" and the European "Giotto". Numerous instruments installed on these devices transmitted to Earth images of the comet's nucleus and various information about its shell. It turned out that the nucleus of Comet Halley consists mainly of regular ice(with small inclusions of carbon dioxide and methane ice), as well as dust particles. They form the comet's shell, and as it approaches the Sun, some of them - under the pressure of solar rays and the solar wind - turn into the tail.
As spectroscopic observations have shown, the glow of the shells of the comet's head and tail is created by gas molecules and dust. The head and tail of the comet are completely transparent. When a comet comes between the Earth and a star, the light of that star reaches us without the slightest weakening. This means that the gases and dust in comets are extremely rarefied. Even with close encounters between comets and small terrestrial planets, it was never possible to notice changes in the planet’s motion under the influence of the comet’s gravity. F.A. Bredikhin, studying the tails of comets, assumed that the repulsive action of the Sun, leading to the appearance of cometary tails, is of an electrical nature. This view was first expressed by M.V. Lomonosov, who wrote about comets: “... the cause of the pale radiance and tails is still unknown, which I without a doubt believe in electric force.” At the same time, comets remain a big mystery for scientists.
Carriers of life
In particular, the phenomenon of so-called subcortical explosions remains unclear. Inside the Earth's orbit, the comet enters a zone of intense heating. At the same time, the core loses tons of its weight every second. And suddenly it was as if a deep mine exploded. Unexplained forces evaporate enormous volumes of ice at depth and at the same time emit huge amounts of gas over a distance of several tens of thousands of kilometers.
It is also completely unclear why periodic comets can repeatedly pass near the very photosphere of the Sun without visible harm to themselves. The passage of a comet near the surface of the Sun is usually accompanied by powerful emissions of solar matter at the point of “contact” - why is also unclear. However, from the moment of perihelion passage by such a bright comet as C/2012 S1, scientists expect extremely interesting phenomena. Perhaps the current comet will shed light on many mysteries of the Universe - in particular, it will help to understand the mystery of the origin of life. After all, many scientists attribute the role of a carrier of life throughout the Universe to comets - this increasingly popular hypothesis is called cosmic panspermia.
The problem of panspermia has been studied by the chief researcher (and until last year, director) of the Paleontological Institute of the Russian Academy of Sciences, academician Alexey Rozanov, for many years. It was he who in our country became the founder of bacterial paleontology - the science of fossil microorganisms, which is rapidly developing throughout the world. One of the important conclusions that this science comes to today is that life, apparently, did not originate on our planet, but was brought from space. “Previously, few people believed in this hypothesis, but today there are more and more supporters,” says Academician Rozanov. - Bacteria are delivered by comets. Meteorites, of course, also participated in this. But in this case, the microbes came to Earth already dead. We have studied hundreds of fragments of such celestial bodies. They may be several billion years old, which is significantly older than the Earth. At the same time, the bacteria in such meteorites are morphologically no different from modern ones, only they are fossilized... With comets it is a completely different matter. The icy “body” of a comet - water environment, in which bacteria were perfectly preserved and could well become “building blocks” for building the foundations of future life and the biosphere on our planet.”
According to Alexey Rozanov, it is on bacterial space data that the modern ideas that much on the Blue Planet came from space and is much older than it. There is a hypothesis that some of the ice aliens gave impetus to earthly epidemics, which at one time decimated entire cities.
This is the secret
The question arises: if all this is true, where did the bacteria in comets come from? After all, it is unlikely that they originated in the body of a tailed traveler. “They probably “lived” on planets where there were puddles, swamps, lakes, and so on,” says Academician Rozanov. - Obviously, planets and pseudo-planets were destroyed, and their fragments traveled through outer space until they hit Earth. There is a point of view that solar system regularly intersects with the flow of matter in the Universe. Perhaps this is where an encounter with “living” cometary meteorites occurs.”...
Although, of course, all this does not shed light on main question- where did life come from? By saying that life could have originated, among other things, on other planets, we only push the problem further away from Earth. We still don’t know for sure how everything came out of the “primordial soup”, whether biochemical processes in the Universe could have given the result that we observe now, and if so, then how. “The smallest bacterium is much more similar to a person than a mixture of chemicals,” writes biology professor Linna Margulis on this subject. - After all, bacteria already have the properties of a biological system. Therefore, it is easier for a bacterium to turn into a person than for a mixture of amino acids to turn into this bacterium.”
Since there are more questions than answers, other, not very scientific hypotheses of the origin of comets arise. They, in particular, say that comets are controlled thermonuclear rockets, with the help of which life spreads throughout the Universe. If this is so, then it is unlikely that their program includes the destruction of planets. Although any, even the most advanced technology is not immune from failure. In this case, perhaps it was an accident spaceship The mystery of the Tunguska explosion is explained. One of many dozens of versions says that it was not a meteorite at all, but an ice alien ship that crashed over the surface of our planet in 1908. Where he was going is a mystery, but clearly not to us.
The Star of Bethlehem is also a comet
Traditionally, comets have been considered harbingers of very significant changes on Earth. The leap year 1680 confirms this. At least in Russia. The culmination of the deepest internal crisis was approaching - the execution of Archpriest Avvakum and the simultaneous end of the reign of Fyodor Alekseevich. And the ancient peoples associated the appearance of comets, translated from Greek as tailed, shaggy celestial bodies, with possible cataclysms on the planet. Their appearance in the sky was treated with sacred horror. They were deified, given names and sacrifices were made to them. The famous researcher of the last century, Immanuel Velikovsky, developed and confirmed with mathematical calculations the elegant hypothesis that Venus, which once escaped from the depths of Jupiter, was a comet, and its approach to the Earth is described in the ancient sources of the Babylonians and Sumerians.
The “tailed beast” inevitably threatened the Earth, but 35 centuries ago, warlike Mars stood in its way, shielding our planet from global destruction. It has long been no news to astrophysicists that the giant northern basin of the Red Planet, covering 40% of its surface, is a trace of the impact of a body comparable to a small planet on Mars. “This happened, apparently, at a time when life on Earth already existed,” believes Igor Mitrofanov, leading researcher at the Institute of Space Research of the Russian Academy of Sciences. - As a result, life, if it existed, died on the Red Planet. Today's exploration of Mars gives reason to believe that this version is absolutely justified. All that remains is to find and study fragments of Martian DNA, which we are now doing with the help of the Russian DAN instrument, which is part of the American Cureosity rover.”
Many legends are associated with the passage of comets near our planet. Russian researcher A.I. Reznikov made an interesting attempt to find a correlation between the Christian legend of Christmas and the appearance in the sky Star of Bethlehem with some events at the time when Halley's Comet was visible. The author was able to identify a number of details (for example, the Trachonite uprising that took place at that time) that speak in favor of his assumption. In other words, from an astrophysical and historical point of view, the moment when, according to Sacred Tradition The birth of the baby Christ coincided with the appearance of Halley's comet in the sky, and it became a kind of happy harbinger for humanity.
Halley's Comet - a harbinger of Chernobyl
This was not always the case. The appearance of Halley's comet is associated with bloody wars and destructive earthquakes, floods and epidemics that claim thousands of lives. IN last time the comet approached Earth in 1986, and its visit was marked by one of the strongest environmental disasters on Earth - an accident on nuclear power plant in Chernobyl. However, whether one is connected with the other is unknown. However, it is difficult to consider the biblical prediction about a star named Chernobyl falling from the sky as an ordinary coincidence. It seems that the warning of the Apostle John came true: “The third angel sounded, and a great star fell from heaven, burning like a lamp, and fell on a third of the rivers and on the springs of water. The name of this star is “Wormwood” (in Ukrainian - Chernobyl - author), and a third of the waters became wormwood, and many of the people died from the waters because they became bitter.”
The comet Typhon mentioned by Plato, which, in his opinion, became a harbinger of the death of Atlantis, also looks quite ominous. The appearance of this comet, according to Plato, was predetermined by Heaven itself due to the peculiarity of some luminaries to deviate from their path and fall to Earth, striking everything with their fire. Recently, Alexander Tollmann, professor of geology at the University of Vienna, confirmed the philosopher’s words with his research. Trying to explain the increased content of dust and volcanic ash about 12 thousand years old in sea bottom sediments, glaciers of Antarctica and Greenland, as well as the “restructuring” of the landscapes of Europe, Asia Minor and America, he studied the folklore of ancient peoples and established a close connection between geological facts and existing this day with legends about the great catastrophe. Perhaps the death of Atlantis is an analogue of the Tunguska explosion, but only in the first case an entire civilization went under water, and in the second case the blow was averted. Is this an accident, and if not, then who did all this and why is a separate conversation.
The nucleus of the “comet that eclipsed the light of the Sun,” according to Tollmann, was at least three kilometers long. in diameter, and upon entering the Earth's atmosphere it broke up into seven large and several small parts that fell onto the surface of the planet. The places where the fragments fell were suggested by Indian, Chinese, Central American and South Pacific legends about “death falling from the sky” - “red hot rains”. Their “drops” are glassy tektites on the coasts of the Tasman and South China Seas, Vietnam, Australia and the islands Indian Ocean- allowed Tollmann to date the disaster at 10-12 thousand years. Cosmic bodies fell with a thunderous roar, dazzlingly bright flashes, causing upon impact a “fire of the mountains,” “flames to the skies,” and multiple earthquakes. Tollmann estimates that the seven fatal impacts triggered earthquakes 400 times stronger than today's. That's when the volcanoes woke up. Smoke from forest fires mixed with volcanic ash. The air temperature rose to 70°C (due to the transfer of hot flows by tornadoes). About a month later, the “great darkness” came. At the same time, continuous downpours, caused by melting glaciers, fell from the sky onto the land. As geologists determined from the limestone rocks of that time, acid rain fell on people and animals (“the water was worse than wormwood”). Nitric acid caused “bloody rains.”
The catastrophic rise in the level of the World Ocean was accompanied by a tsunami - waves up to 100 m high flooded the continents, spreading far from the coast. For example, in the famous Shanidar cave, located at an altitude of 750 m in the mountains of Kurdistan, cultural layers can be traced back over 100 thousand years. But at the level of 10 thousand years BC. e. traces of people disappear, giving way to marine sediments mixed with stones that fell from the ceiling of the cave as a result of earthquakes. And only after five thousand years the cultural layer appears again - just in time, corresponding, according to Christian chronology, to the creation of the world (5508 years BC). Tollmann saw in this an analogy with the verses of the first chapter of the Book of Genesis, like the slow rebirth of the Earth after a great catastrophe.
Russian geophysicist, Doctor of Geological and Mineralogical Sciences, chief researcher at the Institute of Oceanology named after. Shirshov RAS Alexander Gorodnitsky, no less famous as a bard from the generation of the “sixties,” has been searching for Atlantis for many years and does not doubt for a minute that this country actually existed. Many historical and geological facts indicate this. “From the standpoint of modern geological science, I emphasized the historical reality of the death of Sodom and Gomorrah, the Flood, the tsunami that drowned the army of Pharaoh, the ten plagues of Egypt, etc.,” says Alexander Gorodnitsky. “In my constructions, I rely on the theory of lithospheric plate tectonics.”
Gorodnitsky does not exclude the comet version of the death of Atlantis, as well as the connection of other major historical events with the appearance of periodic comets. In addition to astrophysical forecasts that would help calculate the flight path of the next celestial guest, he advises reading... biblical texts. “In many parts, they absolutely document certain events that occurred on our planet,” says the scientist. “The more carefully we study them, the more unexpected discoveries they will present.”
Consider variable stars: description of the star class, why they can change brightness, duration of change in magnitude, solar fluctuations, types of variables.
Variable called star, if it is capable of changing brightness. That is, its apparent magnitude, for some reason, periodically changes for an earthly observer. Such changes can take years, sometimes only seconds, and range between 1/1000th of a magnitude and 20th.
Among the representatives of variable stars, more than 100,000 celestial bodies were included in the catalogs, and thousands more act as suspicious variables. is also a variable whose luminosity fluctuates by 1/1000th of a magnitude and whose period spans 11 years.
History of Variable Stars
The history of the study of variable stars begins with Omicron Ceti (Mira). David Fabricius described it as new in 1596. In 1638, Johannes Hogvalds noticed its pulsation for 11 months. This was a valuable discovery, since it suggested that the stars were not something eternal (as Aristotle claimed). Supernovae and variables helped to step into new era astronomy.
After that, in just one century it was possible to find 4 type variables Mira. It turned out that they were known about before appearing in the records of the Western world. For example, three were listed in the documents Ancient China and Korea.
In 1669, the variable eclipsing star Algol was discovered, although its variability was only explained by John Goodrick in 1784. The third is Chi Swan, found in 1686 and 1704. Over the next 80 years, 7 more were found.
Since 1850, a boom in the search for variables began, because photography was actively developing. Just so you understand, since 2008 there have been more than 46,000 variables alone.
Characteristics and composition of variable stars
Variability has reasons. This applies to changes in luminosity or mass, as well as some obstacles that prevent light from reaching. Therefore, types of variable stars are distinguished. Pulsating variable stars inflate and contract. Double eclipses lose brightness when one of them overlaps the other. Some variables represent two nearby stars exchanging mass.
Two main types of variable stars can be distinguished. There are internal variables - their brightness changes due to pulsation, change in size or eruption. And there are external ones - the reason lies in the eclipse that occurs due to mutual rotation.
Internal variable stars
Cepheids- incredibly bright stars, exceeding solar luminosity by 500-300,000 times. Frequency – 1-100 days. This is a pulsating type, capable of rapidly expanding and contracting over time. short term. This valuable objects, since they are used to measure distances to other celestial bodies and formations.
Other pulsating variables include RR Lyrae, which has a much shorter period and is older. There are RV Taurus - supergiants with noticeable wobble. If we look at stars with a long period, then these are objects like Mira - cold red supergiants. Semi-regular - red giants or supergiants, whose periodicity takes 30-1000 days. One of the most popular is .
Don't forget about the Cepheid variable V1, which has made its mark in the history of the study of the Universe. It was with her help that Edwin Hubble realized that the nebula in which it was located was a galaxy. This means that space is not limited to the Milky Way.
Cataclysmic variables (“explosives”) glow due to sudden or very powerful flashes created by thermonuclear processes. Among them are novae, supernovae and dwarf novae.
Supernovae- are dynamic. The amount of energy emitted sometimes exceeds the capabilities of the entire galaxy. They can grow to magnitude 20, becoming 100 million times brighter. Most often, they are formed at the moment of death of a massive star, although after this a core (neutron star) may remain or a planetary nebula may form.
For example, V1280 Scorpii reached its maximum brightness in 2007. Over the past 70 years, Nova Cygnus has been the brightest. Everyone was also amazed by V603 Orla, which exploded in 1901. During 1918, it was no less bright.
Dwarf novae are double white stars that transfer mass and produce regular outbursts. There are symbiotic variables - close dual systems, which features a red giant and a hot blue star.
Eruptions are noticeable by eruptive variables capable of interacting with other substances. There are a lot of subtypes: flaring stars, supergiants, protostars, Orion variables. Some of them act as binary systems.
External variable stars
TO eclipsing refer to stars that periodically block each other's light in observation. Each of them may have its own planets, repeating the eclipse mechanism that occurs in. Algol is such an object. NASA's Kepler mission managed to find more than 2,600 eclipsing binary stars during its mission.
Rotating are variables that exhibit small variations in light created by surface spots. Very often these are double systems formed in the form of ellipses, which causes changes in brightness during movement.
Pulsars- Rotating neutron stars that produce electromagnetic radiation that can only be seen if it is directed towards us. Light intervals can be measured and tracked because they are precise. Very often they are called space beacons. If a pulsar rotates very quickly, it loses a huge amount of mass per second. They are called millisecond pulsars. The fastest representative is capable of making 43,000 revolutions in a minute. Their speed is explained by gravitational connection with ordinary stars. During such contact, the gas moves from normal to pulsar, accelerating its rotation.
Future research on variable stars
It is important to understand that these celestial bodies are extremely useful to astronomers, as they allow them to understand the radii, mass, temperature and visibility of other stars. In addition, they help to penetrate the composition and study the evolutionary path. But studying them is a painstaking and lengthy process, for which not only special instruments are used, but also amateur telescopes.
Some variables are especially important, such as Cepheids. They help determine the age of the entire Universe and reveal the secrets of distant galaxies. Variables of the World reveal the secrets of our Sun. Supernovae reveal a lot about the expansion process. The cataclysmic ones contain information about active galaxies and supermassive black holes. Therefore, variable stars can explain why some things in the Universe are not stable.