About the night sky (). night starry sky

This article is about the sky. Here you can read reflections and reasoning about the sky. The material will be presented in the form of a story. The story about the sky, the impressions and observations of mankind associated with it, will not leave you indifferent. Clouds, sun and stars - all this it gives us. So, let's begin.

Such a different mood

Every person, regardless of their age, loves to look at the sky. Whether it's a grey-haired old man or a toothless kid, each of them finds their charms in him. It is like a mood, now “good”, warm, high, piercingly blue, then suddenly “frowns”, white clouds, so fluffy, suddenly become gray and unfriendly, it starts to rain. So is the mood, changeable, or excellent, sunny and bright, or cloudy, like a rainy autumn in St. Petersburg ... It was painted, photographed, studied, or simply admired.

Seasons

Like the weather, it has its own characteristics at different times of the year. The story about the sky in summer and spring will be bright and sunny, like these seasons. When the sky is high and piercing, blue or pale blue, the sun shines brightly in the sky, endowing all life on earth with its warmth. Joyfully and warmly becomes around. gardens bloom, fields and meadows turn green. Above all this splendor stretches a calm and fertile sky. Only occasionally at this time is it covered with clouds, and if this happens, then perhaps in May, when spring showers with thunderstorms generously water the earth. The sky gives her plenty to drink, in response to this, the grateful earth gives a harvest, gardens begin to bloom and forests come to life. After spring and summer showers, you can often see a rainbow in the sky. Such a beautiful sight! Make a wish! It will definitely come true.

The sky will be completely different. The sky is no longer what it used to be. Low and gloomy, gray and inhospitable, maybe even a little tired after the sweltering summer heat. You can often see a wedge of birds flying to warmer climes in the sky. It rains more often, clouds envelop the sky, which are not at all like summer fluffy, snow-white clouds. Now these are gray and heavy clouds that are ready to “cry” sadly for many hours.

The story about the sky in winter will be short and faceless, just like the sky itself. You can say that it is “sleeping”, waiting for awakening, which will come soon, in the spring. The sky seems to be in a "bad mood".

Day and night

The daytime sky is sunny, pale blue, but the night sky is mysterious and alluring. A story about the night sky can be like magic. It is covered with stars, especially many of them can be seen outside the city, where there are no high-rise buildings. From such beauty dizzy, the stars beckon and call to themselves. Each star forms constellations. Just think about how many centuries people have studied them, continue to study and discover something new, unknown. The bottomless night sky resembles a blanket in which you want to turn around, warm up, fall asleep under the lulling sparkle of stars. When you remember what it really is, it somehow immediately pops up in your memory, how the cricket “sings”, how pleasantly the coolness of a summer night envelops, how the waves rustle.

Clouds - "white-maned horses"

“Shake! Hello!". This greeting is borrowed from the Soviet cartoon of 1980, where a children's kind song sounds, which is familiar to each of us. From this cartoon, and from the song itself it breathes childhood, warmth and endless joy. More than once or twice, raising your head, looking at the clouds, you remember the words from this wonderful song. A youth musical group called "Keys" covered this song, the effect was incredible! Not a single word was changed, but the musical accompaniment was completely replayed. The video clip is “adult”, pilots and the sky, planes and the sky, so the words from the children's song take on a completely different meaning! The effect is like an exploding bomb. And here again the sky is so different, beautiful and dangerous, dear and at the same time distant. How much joy it gives people when contemplating and admiring it, how many lives it can take. And therein lies its charm.

The story about the sky and clouds is so attractive for boys, many of whom dream about it, want to soar into the heavenly distance, rise high above their native expanses, look around the fields and plains, see their city from a bird's eye view. The dream associated with the sky is to become a pilot and conquer the expanses of heaven.

Impressions and observations

In the story about observing the sky, one very important conclusion can be drawn: it can change instantly and absolutely unpredictably. From gentle and playful, blowing with a gentle breeze, it can become gloomy and gloomy. But the clouds dissipate and give place to the sun. You can also observe the seven-color miracle of nature - the rainbow. It's nice to look at such a spectacle, I want to reach out to it and run along this colorful path. But besides the rainbow after the rain, you can observe another natural phenomenon - a thunderstorm. Gray gloomy clouds collide with their edges, lightning flashes from this collision in an electrolyzed atmosphere. In addition to lightning, there are also sounds of thunder, the appearance of which is also associated with the presence of electrical discharges.

Each person perceives a thunderstorm in the sky differently. For some, this is an inconvenient misunderstanding: you have to wait, cancel or delay trips. And for someone - a reason to remember childhood, when we joyfully and carelessly ran in the rain. Rain poured down from the gray sky. In this combination, the weather causes conflicting feelings. The rain pleases, it will water the earth, and then a rich harvest will rise. But rain and lingering skies can cause sadness and feelings of loneliness. Yes, of course, it can be sadness, but you can spend a rainy evening in the company of an interesting book. And it can also be a romantic rain with kisses, with wet clothes and hopelessly ruined hair. But it will be the best rain.

Conclusion

Whatever the sky, there will always be dreamers and romantics who will strive to unravel the secrets that it keeps in itself. The attraction of the bottomless depth of the unknown space will never disappear, beckoning us to other galaxies. The story about the sky gives so many emotions, sensations. And for children it will be a cognitive process that develops their powers of observation, allowing them to be closer to nature.

Some babies are quite difficult to put to bed: either they haven’t played enough, then they are tormented by unreasonable fears, and sometimes they just don’t want to stay in the room all alone. The starry sky nightlight projector Star Master, which will be discussed in today's material, will be a great helper for young parents in the difficult process of raising children, and will also be an excellent addition to the arsenal of any romance, and indeed anyone who is not alien to beauty. We will try to tell everything about the unusual lamp, starting with its detailed description and purpose, and ending with recommendations and customer reviews.

Stars, night, romance

Have you ever dreamed of having your own observatory at home? Falling asleep every night under a deep starry sky, dreaming about the future? Now all this is possible, as the starry sky nightlight projector Star Master gives such an opportunity. Plunging into a fairy tale is now real, and making it easier than ever. You just need to run this lamp indoors without additional lighting and the infinite universe will envelop the room. Hundreds of stars will be displayed on the walls and ceiling, giving a state of deep aesthetic pleasure and enjoyment of the star compass that has opened right in the apartment. But the endless night sky is far from all that a small lamp is capable of. In its arsenal, there are several room lighting modes, each of which will find the right application at a particular moment and according to the appropriate mood.

A thing that has no age restrictions and other requirements

Night light projector of the starry sky Star Master Dream can be presented for a birthday, New Year or any other holiday to absolutely everyone: mom, girlfriend, sister, brother, husband or boyfriend. Any of the above will appreciate the beauty that occurs at the moment the night light is turned on. Everyone will want to use such a night light, because falling asleep under a star-studded sky is beautiful, pleasant and romantic. All you need to do is get into bed and turn on the Star Master night light. By the way, such a night light will be an excellent source of light for young parents, for example, during the night changing clothes of a child or feeding. Pediatricians and psychologists tend to conclude that it is not worth disturbing the baby with bright light at night, because this can easily disrupt natural biorhythms and discourage the baby from sleeping when needed. Often, inexperienced mothers neglect such advice from professionals and face a problem when a child confuses day with night: he sleeps during daylight hours and stays awake at night.

Night light-projector of the starry sky Star master: description

The lamp has the shape of a cylinder with holes made by a special machine and special colored bulbs inside, of which there are three. The walls of the night light are curved in accordance with the required angles at which the stars should be located. The side faces are covered with a special stencil with stars of various shapes and sizes embossed on it. Also at the bottom there is a ring for adjusting the month of the starry sky. Set the season to your liking, and then enjoy the deepest winter skies in the middle of a hot summer night, or feel the fall starfall for the second time in a year, simply by turning the dial to your desired position. The kit can be supplied with both batteries and a whole network adapter for connecting to the network and a longer operating time. Some models have a USB cable with the ability to connect the device to a computer or laptop. Next to the power button is a mode switch, with which you can adjust the flickering of colored lights located inside the lamp. Depending on the cost of the night light, there can be up to 7 such modes.

Even a child can handle the projector

Usually, instructions are not included with the Star Master night light projector, since the principle of its operation is extremely simple, and the device is intuitive. The luminaire has an on/off switch, a place under the cover designed to install batteries (3 pieces of AA type) if autonomous operation of the luminaire is required. There is a connector for connecting a constant power supply via a network adapter, which allows you to leave the nightlight on for a long time and not worry about the periodic replacement of batteries.

Types of fixtures

For several years in a row, the Star Master night light projector of the starry sky, the photo of which is presented in this material, becomes a long-awaited gift or a necessary purchase for any family where they learned about it. By the way, prices for a lamp range from seven dollars to twenty. This is from 500 to 1500 rubles. Based on the cost, the night light will be endowed with some functions or, conversely, deprived of them. So, for example, the situation is with the mode switch by months: the budget model does not have this function, but in the more expensive ones, the lamp rotates, allowing you to change the lighting modes.

There are more than nine types of Star master nightlight projectors on the market:

1. "Star Master" is normal.
2. star beauty.
3. Star Lover, of which there are 4 different modifications.
4. oceanmaster.
5. Constellation Master.
6. Universe Master.
7. Night light projector of the starry sky Star Master Dream rotating projection lamp. Such a lamp is slightly different from all of the above, because it is not cylindrical, but round. It has a brighter spectrum of white, which allows the stars and the moon to be projected much more clearly on the ceiling and walls of the room. Also an important difference of the Dream model is the function with the ability to switch the flickering of colored lights (blue, red and yellow). They can both alternate with each other, so completely turn off.

Pleshakov had a good idea - to create an atlas for children, by which it is easy to determine the stars and constellations. Our teachers picked up this idea and created their own key atlas, which is even more informative and visual.

What are constellations?

If you raise your eyes to the sky on a clear night, you can see a lot of sparkling lights of various sizes, which, like a scattering of diamonds, adorn the sky. These lights are called stars. Some of them seem to be collected in clusters and after a long examination they can be divided into certain groups. These groups are called "constellations". Some of them may resemble the shape of a bucket or the intricate outlines of animals, however, in many ways, this is just a figment of the imagination.

For many centuries, astronomers tried to study such clusters of stars and gave them mystical properties. People tried to systematize them and find a common pattern, and so the constellations appeared. For a long time, the constellations were carefully studied, some were broken into smaller ones, and they ceased to exist, and some were simply corrected after clarification. For example, the constellation Argo was divided into smaller constellations: Compass, Carina, Sail, Korma.

The history of the origin of the names of the constellations is also very interesting. To facilitate memorization, they were given names united by one element or a literary work. For example, it was noticed that during heavy rains the Sun rises from the side of certain constellations, which were given the following names: Capricorn, Whale, Aquarius, the constellation of Pisces.

In order to bring all the constellations to a certain classification, in 1930, at a meeting of the International Astronomical Union, a decision was made to officially register 88 constellations. According to the accepted decision, the constellations do not consist of groups of stars, but are sections of the starry sky.

What are the constellations?

Constellations differ in the number and brightness of the stars that make up its composition. Allocate 30 most noticeable groups of stars. The largest constellation in terms of area is Ursa Major. It consists of 7 bright and 118 stars visible to the naked eye.

The smallest constellation located in the southern hemisphere is called the Southern Cross and cannot be seen with the naked eye. It consists of 5 bright and 25 less visible stars.

The Little Horse is the smallest constellation in the northern hemisphere and consists of 10 faint stars that can be seen with the naked eye.

The most beautiful and brightest constellation is Orion. It consists of 120 stars visible to the naked eye and 7 of them are very bright.

All constellations are conventionally divided into those located in the southern or northern hemisphere. Those who live in the southern hemisphere of the Earth cannot see the clusters of stars located in the northern hemisphere and vice versa. Of the 88 constellations, 48 ​​are in the southern hemisphere and 31 are in the northern. The remaining 9 groups of stars are located in both hemispheres. The northern hemisphere is easy to identify by the North Star, which always shines very brightly in the sky. She is the extreme star on the handle of the Ursa Minor bucket.

Due to the fact that the Earth revolves around the Sun, which does not allow seeing some constellations, the seasons change and the position of this luminary in the sky changes. For example, in winter, the position of our planet in the circumsolar orbit is opposite to that in summer. Therefore, only certain constellations can be seen at any time of the year. For example, in the summer, a triangle formed by the stars Altair, Vega and Deneb can be seen in the night sky. In winter, there is an opportunity to admire the infinitely beautiful constellation Orion. Therefore, sometimes they say: autumn constellations, winter, summer or spring constellations.

The constellations are best seen in the summer and it is advisable to observe them in open space, outside the city. Some stars can be seen with the naked eye, while others may require a telescope. The constellations Ursa Major and Ursa Minor, as well as Cassiopeia, are best seen. In autumn and winter, the constellations Taurus and Orion are clearly visible.

Bright constellations that are visible in Russia

The most beautiful constellations of the northern hemisphere visible in Russia include: Orion, Ursa Major, Taurus, Canis Major, Canis Minor.

If you peer into their location and give free rein to your imagination, you can see a hunting scene, which, like an ancient fresco, has been depicted in the sky for more than two thousand years. The brave hunter Orion is always depicted surrounded by animals. Taurus runs to his right, and the hunter swings a club at him. At the feet of Orion is the faithful Great and Lesser Dogs.

Constellation Orion

This is the largest and most colorful constellation. It is clearly visible in autumn and winter. Orion can be seen over the entire territory of Russia. The arrangement of its stars resembles the outlines of a person.

The history of the formation of this constellation originates from ancient Greek myths. According to them, Orion was a brave and strong hunter, the son of Poseidon and the nymph Emvriala. He often hunted with Artemis, but one day, for defeating her during a hunt, he was hit by an arrow of the goddess and died. After his death, he was turned into a constellation.

The brightest star in Orion is Rigel. It is 25 thousand times brighter than the Sun and 33 times its size. This star has a bluish-white glow and is considered supergiant. However, despite such an impressive size, it is much smaller than Betelgeuse.

Betelgeuse adorns Orion's right shoulder. It is 450 times the diameter of the Sun, and if you put it in the place of our luminary, then this star will take the place of four planets before Mars. Betelgeuse shines 14,000 times brighter than the Sun.

The constellation Orion also includes a nebula and asterisms.

Constellation Taurus

Another large and unimaginably beautiful constellation of the northern hemisphere is Taurus. It is located northwest of Orion and lies between the constellations Aries and Gemini. Not far from Taurus are such constellations as: Charioteer, Keith, Perseus, Eridanus.

This constellation in mid-latitudes can be observed throughout almost the entire year, with the exception of the second half of spring and early summer.

The history of the constellation goes back to ancient myths. They talk about Zeus, who turned into a calf in order to kidnap the goddess Europa and bring her to the island of Crete. This constellation was first described by Eudoxus, a mathematician who lived long before our era.

Aldebaran is the brightest star not only in this constellation, but also in other 12 groups of stars. It is located on the head of Taurus and used to be called the "eye". Aldebaran is 38 times the diameter of the Sun and 150 times brighter. This star is located at a distance of 62 light years from us.

The second brightest star in the constellation is Nat or El Nat (bull horns). It is located near the Auriga. It is 700 times brighter than the Sun and 4.5 times larger than it.

Within the constellation are two incredibly beautiful open clusters of stars Hyades and Pleiades.

The age of the Hyades is 650 million years. They can be easily found in the starry sky thanks to Aldebaran, which is perfectly visible among them. They include about 200 stars.

The Pleiades got their name from the nine parts. Seven of them are named after the seven sisters of Ancient Greece (Pleiades), and two more are named after their parents. The Pleiades are very visible in winter. They include about 1000 stellar bodies.

An equally interesting formation in the constellation of Taurus is the Crab Nebula. It was formed after a supernova explosion in 1054 and was discovered in 1731. The distance of the nebula from the Earth is 6500 light years, and its diameter is about 11 light years. years.

This constellation belongs to the Orion family and borders on the constellations Orion, Unicorn, Canis Minor, Hare.

The constellation Canis Major was first discovered by Ptolemy in the second century.

There is a myth that Big Dog used to be Lelap. It was a very fast dog that could catch up with any prey. Once he chased a fox, which was not inferior to him in speed. The outcome of the race was a foregone conclusion, and Zeus turned both animals to stone. He placed the dog in heaven.

The constellation Canis Major is very visible in winter. The brightest star not only in this, but in all other constellations is Sirius. It has a bluish luster and is located quite close to Earth, at a distance of 8.6 light years. In terms of brightness in our solar system, it is surpassed by Jupiter, Venus, and the Moon. The light from Sirius reaches the Earth after 9 years, and it is 24 times stronger than the sun. This star has a satellite called "Puppy".

Sirius is associated with the formation of such a thing as "Vacation". The fact is that this star appeared in the sky during the summer heat. Since Sirius in Greek is called "canis", the Greeks began to call this period holidays.

Constellation Canis Minor

Small Dog borders on such constellations as: Unicorn, Hydra, Cancer, Gemini. This constellation represents the animal that, along with Canis Major, follows the hunter Orion.

The history of the formation of this constellation, if you rely on myths, is very interesting. According to them, the Small Dog is Mera, the dog of Ikaria. This man was taught to make wine by Dionysus and this drink turned out to be very strong. One day his guests decided that Ikaria decided to poison them and killed him. The mayor was very sad for the owner and soon died. Zeus placed it in the form of a constellation in the starry sky.

This constellation is best observed in January and February.

The brightest stars in this constellation are Portion and Gomeisa. Portion is 11.4 light-years from Earth. It is somewhat brighter and hotter than the Sun, but physically differs little from it.

Gomeisa is visible to the naked eye and glows with a blue-white light.

Constellation Ursa Major

Ursa Major, shaped like a bucket, is one of the three largest constellations. It is mentioned in the writings of Homer and in the Bible. This constellation is very well studied and is of great importance in many religions.

It borders on such constellations as: Waterfall, Leo, Hounds Dogs, Dragon, Lynx.

According to ancient Greek myths, Ursa Major is associated with Callisto, a beautiful nymph and beloved of Zeus. His wife Hera turned Callisto into a bear as punishment. One day, this bear stumbled upon Hera and their son, Arkas, with Zeus. To avoid tragedy, Zeus turned his son and nymph into constellations.

The big bucket is formed by seven stars. The most striking of them are three: Dubhe, Alkaid, Aliot.

Dubhe is a red giant and points to the North Star. It is located 120 light years from Earth.

Alkaid, the third brightest star in the constellation, expresses the end of the tail of Ursa Major. It is located at a distance of 100 light years from Earth.

Alioth is the brightest star in the constellation. She represents the tail. Because of its brightness, it is used in navigation. Alioth shines 108 times brighter than the Sun.

These constellations are the brightest and most beautiful in the northern hemisphere. They can be perfectly seen with the naked eye on an autumn or frosty winter night. The legends of their formation allow fantasy to run wild and imagine how the mighty hunter Orion, together with his faithful dogs, runs after prey, while Taurus and Ursa Major are watching him carefully.

Russia is located in the northern hemisphere, and in this part of the sky we manage to see only a few of all the constellations that exist in the sky. Depending on the season, only their position in the sky changes.

The starry sky… Enchanting, alluring, flickering with thousands of lights, bottomless and endless, so close and at the same time so far away… Not the one that is illuminated by the night city or street lamps, but the one that is far from civilization, such that space darkness is visible . For this, it is not necessary to go to the mountains or to the steppe. It is enough to go ten kilometers from the settlement and retire, for example, in a river valley or in a clearing surrounded by forest at some distance.

First Most of the photos are clickable, to enlarge it, click on the picture:
1. Summer sky of the Astronomical City; 2. Starry sky in the mountains.

Starry sky for me from early childhood it was the most important mystery and at the same time the most sacred dream. I loved to lie for a long time on a haystack near my village house and admire this endless, shimmering beauty. And to dream… That it would be nice to have the ability of an astronaut and to fly into space with superluminal speed on a ship in order to be close by and touch the magic of the most unusual cosmic worlds. With these thoughts, while inside the visualized, vivid images of the space traveler, I often fell asleep in my bed. As a child, I found a map and learned all the constellations in the sky.

The most beloved and desired for me as a child were science fiction films on a space theme. During their show, I mentally disappeared from my space and was there, in the cosmic worlds, along with the heroes of the films. It is a pity that then (70s) these films were very rare on television (only a couple of times a year). I remember what a strong emotional outburst I received during the first viewing of color space fiction in the city cinema, when I became a university student. The library in the village school was weak, there were no books on the subject of space fantasy. I remember the emotional shock I received when, in the 9th grade, a teacher brought a voluminous collection of fantastic novels and short stories. I read until morning. The next book was "The Bull's Hour" by Ivan Efremov...

Among my classmates, school friends and children's environment, there was no one who was so fond of and admired the starry sky. It seemed strange to me then. Now it is clear why. After all, the cosmos is one of the channels here on Earth, which makes us ask questions - who am I, where am I from, where am I, why am I. And if a person is not ready to seek and receive answers to these questions due to the young age of the soul, or due to the lack of experience and knowledge recorded in his spiritual memory, then he does not have a strong craving and powerful delight from the contemplation of the starry distances. I will say more, after passing the “line” of spiritual transformation, when a person from speaking about love becomes spiritually loving, when answers to the above sacred questions are received, the delight and pleasure from being under the starry sky and contemplating the constellations only intensifies ...

Stars. About one star, the most important for us, - - I have already written in detail earlier. The Sun is a small, calm, single star of the spectral class G (G2V - "yellow dwarf"), one of 200 - 300 billion in our galaxy. An ordinary star, not distinguished by anything special. Most of them. Therefore, with regard to the structure of stars, their luminosity and life, then there is no point in repeating it.It is worth noting here what is characteristic of other stars and star systems, but is not characteristic of the Sun.

The photo is clickable, to enlarge it, click on the picture:
1. Pleiades; 2. Witch in the light of the stars.

With the naked eye, about 3,000 stars are visible in the sky in each hemisphere (northern and southern), about 6,000 in total. Powerful ground-based telescopes can increase this figure millions of times.

1. Star clusters in NGC 1313; 2. Star cluster M34; 3. M39 - open cluster in Cygnus; 4. Kemble Cascade.

There are so many stars in our galaxy that only about 0.01% of their number is listed in catalogs. The rest have not yet been identified and counted. The most famous stars are the North Star, Sirius, Vega, Aldebaran, Arcturus, Rigel, Mizar, Algol and others. According to the established tradition, supported by astronomers, only about 300 bright stars have their own names. There are no officially assigned names for the stars. As a result, star naming certificates issued by some organizations are a private initiative and are not recognized by the International Astronomical Union.

The first photo is clickable, to enlarge it, click on the picture:
1. Constellations Draco and Ursa Minor; 2. Constellation Ursa Major.

Even ancient people mentally connected the brightest stars with lines and the resulting geometric shapes or patterns - constellations- called names. For example, Ursa Major, Ursa Minor, Orion, Cassiopeia, Sagittarius, Lyra, Swan, Andromeda, Pegasus, etc. As a rule, the names of the constellations were consonant with the characters of myths and legends. Thus, constellations are rather large, conditionally delineated sections of the celestial sphere, each of which contains several bright stars that are clearly visible to the naked eye. Later, star atlases appeared, based on the constellations, accompanied by beautiful drawings of mythical characters. In them, the stars were designated by the letters of the Greek alphabet in descending order of their brightness: α is the brightest star in the constellation, β is the second brightest, and so on. The stars included in the constellation are not necessarily close to each other in space.

1. The constellation of Orion in the sky; 2. The constellation of Orion on a star map.

It seems that in the sky the stars are not far from each other. In fact distances between them, even by cosmic standards are huge. The closest star to Earth (other than the Sun) is Proxima Centauri. It is located 4.2 light years (or 39 trillion km = 3.9 × 10 13 km) from the solar system (1 light year is the distance that light travels in outer space in one year). The brightness of a star in the sky is related not only to its distance from the Earth, but also to the size of the star itself and its luminosity.

Stars differ from each other in many ways. First of all, by bloom. There are stars blue, white-blue, white, yellow-white, yellow, orange and red. The color of a star depends on the temperature of its surface. The hottest stars are blue (up to 60,000 Kelvin on the surface), the coldest are red (2000 - 3500 K). In general, it is very difficult to determine the color of faint stars with the naked eye, while in photographs it is easily distinguishable. The color of stars is much easier to determine when observing through a telescope. It should also be borne in mind that observers perceive color differently: some eyes are more sensitive to blue rays and have difficulty distinguishing red stars, or vice versa.

The second distinguishing feature is brightness star, which is estimated in stellar magnitudes. Thus, a star that is perceived by the eye as a star of the first magnitude is almost twice as bright as a star of the second magnitude, which, in turn, is as much brighter than a star of the third magnitude, and so on. Stars up to 6th magnitude are visible to the naked eye. A first magnitude star is exactly 100 times brighter than a sixth magnitude star. So it is accepted that the brightest stars have negative magnitudes.

1. The star Betelgeuse as seen through the Hubble telescope; 2. Spotted surface of the star Betelgeuse.

The third distinguishing feature is size stars. Here the ratio between the smallest and largest reaches even greater values. The picture on the left shows the comparative size of the Sun (small dot on the left, bottom) with the blue star LBV 1906-20.

Another picture on the left, if you click on it, will open a large drawing that clearly shows the sizes of the stars in comparison. And below are two videos where this comparison of the Earth and the Sun with other stars is even more impressive.

These videos can be downloaded from YOUTUBE at http://www.youtube.com/watch?v=VEa0RiU5aeU And http://www.youtube.com/watch?v=kdUAus2-RXg

Masses stars change in a much more modest range and in the majority range from 0.07 to 100-150 solar masses. There are also heavier ones, but such massive stars are very rare. Stars vary greatly in density. Among them there are those whose cubic centimeter of substance outweighs a large loaded ocean ship. For example, the density of matter in a white dwarf is a million times higher than that of water. And in a neutron star, which is only a few kilometers in size, the density of matter is 280 trillion times that of water. The matter of other stars is so rarefied that its density in the surface layers is less than the density of the vacuum that is achievable under terrestrial laboratory conditions.

There are the following types of stars: brown dwarfs, white dwarfs, red giants, variables, Wolf-Rayet and T Tauri stars, novae, supernovae and neutron stars. More details about this can be found in the materials, links to which are given at the end of the text.

Photos are clickable, to enlarge them, click on the picture:
1. M13 - a huge globular star cluster; 2. Millions of stars in Omega Centauri.

By number of stars, connected in a group, single and multiple (double, triple and higher multiplicity) star systems are distinguished. If a system contains more than ten stars, it is called a star cluster. Our Sun is a single star. Double (multiple) stars are very common in the galaxy (more than 70% of the stars). For example, the brightest of the visually observed stars in the sky, Sirius, is a double (next to it, another white dwarf rotates around a single gravitational center).

Different types of stars go through different evolution. Its main stages are as follows: the birth, life on the main sequence, the final stage and the death of a star. Stars are born from gas and dust clouds when gravitational compression and heating of matter occurs to temperatures that trigger thermonuclear processes. Star-forming regions are usually revealed by the presence of massive hot and bright (young) stars. I end my life, depending on the class, ordinary stars either turn into white dwarfs, neutron stars or pulsars, or fade and become invisible ("black" dwarfs), or explode as supernovae, or turn into black holes.