For the 12th year now, Cassini has been delighting us with magnificent images of Saturn. But in addition to the gas giant itself and its satellites, other interesting objects also fall into the camera lens of the device. For example, . Or . Or, as in the image below, the Alpha Centauri system captured above the planet's horizon.

In the photo you can see two of the three stars of the system. Alpha Centauri A is similar to our star. Its mass is 1.14 solar, its radius is 1.23 solar, and its age is estimated at six billion years. It orbits around a common center of mass with the star Alpha Centauri B. It is an orange dwarf with a mass of 0.91 and a radius of 0.87 solar. The distance between this pair varies from 11 to 35 AU, they make one revolution around each other in about 80 Earth years.

But what you won’t see in the picture is Proxima Centauri. But this is not surprising; red dwarfs are very dim. Even if Proxima were a light year away from the Sun, it would still not be visible to the naked eye. It is separated from the Alpha Centauri A/B pair by a distance of 15 thousand AU. Proxima is believed to be part of the system, but there is still some uncertainty about this.

In this image, Proxima Centauri is circled in red.

The distance from the Sun to Proxima is 4.24 light years, to Alpha Centauri A/B - 4.36 light years. If in kilometers, then this is approximately 39.92 trillion kilometers to Proxima, and 41.2 trillion to Alpha Centauri. At its current speed, Voyager 1 would take 74,400 years to reach Proxima and 76,870 years to reach Alpha Centauri. This is, of course, provided they agreed to stand still while awaiting his visit.

MOSCOW, October 17 - RIA Novosti. Astronomers from the European Southern Observatory have discovered an Earth-mass planet in the closest star system to Earth, the star Alpha Centauri B, according to a paper to be published in the journal Nature.

The Alpha star system of the Centaurus constellation is the brightest star in the southern sky and the closest to the solar system.

It is a triple star, consisting of two stars similar to the Sun - Alpha Centauri A and Alpha Centauri B - and a third, distant from them, Proxima Centauri. Proxima, a dim red dwarf, is the closest star to the Sun. It is located about 4.24 light years from Earth, about 0.2 light years closer than stars A and B. However, this faint star cannot be seen with the naked eye.

Since the 19th century, astronomers have speculated about the possibility of the existence of planets in this system, which could be the closest haven of life to the solar system. But the accuracy of astronomical methods has not yet made it possible to judge whether these stars closest to Earth have planets. Now such a planet has been found.

"Over four years of observations with the HARPS instrument, we have detected a faint signal that indicates the existence of a planet orbiting the star Alpha Centauri B with a period of 3.2 days," says Xavier Dumusque, lead author. research, quoted by the press service of the European Southern Observatory.

European astronomers used the radial velocity method to search for the planet - a method based on measuring the extremely small “swings” of the star that occur under the influence of the planet’s gravity. The HARPS spectrograph, installed on a telescope with a mirror diameter of 3.6 meters at the La Silla Observatory in Chile, recorded the Doppler shift of the spectrum arising from this “increase”. This effect is extremely weak - the planet causes the star Alpha Centauri B to move back and forth at a speed of about 51 centimeters per second, which requires extreme precision to measure.

The star Alpha Centauri B is similar to the Sun, with a mass of 0.9 solar masses and a luminosity of about half that of the Sun. The planet, discovered by European astronomers, orbits once every 3.236 days, and its orbital radius is only 0.04 astronomical units (5.98 million kilometers), which is about ten times smaller than the radius of Mercury's orbit (0.46 astronomical units) .

The planet's mass is at least 1.13 Earth masses. The radial velocity method allows one to estimate only the lower limit of the planet’s mass, but experience shows that it is most often close to the real one.

The second component of the binary system, the star Alpha Centauri A, is hundreds of times further away - about the distance separating the Sun and Saturn - but in the sky of this planet it should shine very brightly.

"This is the first planet with a mass close to the mass of Earth found around a star similar to the Sun. It orbits very close to its star and must be too hot to support life, but it may be just one of several planets that could exist in this system," says study co-author Stephane Udry.

Alpha Centauri system

Proxima Centauri is located 4.22 light years from the Sun. This is the closest star to us of all the stars known today.. It can only be seen through a telescope as an 11th magnitude object in the southern constellation Centaurus. This small red star, a member of the triple star system Alpha Centauri (see image at left), was only discovered in 1915 by Scottish astronomer Robert Innes (1861 - 1933). The brightest star in the system is Alpha Centauri A (4.35 light years from the Sun), called Rigel (leg) of Centauri - the brightest star in the constellation. It is very similar to our Sun, but is located further than Proxima. Alpha Centauri A has been known since ancient times, being the fourth brightest star in the night sky. The bright stars Alpha Centauri A and B form a close binary system. The distance between them is 23 astronomical units, which is slightly greater than the distance from the Sun to Uranus. But Proxima is located at a distance of 13,000 AU from this pair. (or 0.2056 light years, which is 400 times the distance from the Sun to Neptune). They all revolve around a common center of mass, but the orbital period of Proxima Centauri is millions of years, so it will remain “closest” for us for a long time (in 9000 years, the closest star to the Sun will be Barnard’s Star, which is rapidly moving in our direction).

Proxima Centauri is not only the closest to us, but also the smallest of the trio. Its mass is so small that it is barely enough to support the process of synthesis of helium from hydrogen in the depths and glow dimly. It is approximately seven times lighter than the Sun, and its surface temperature is “only” 3000 degrees, which is half that of our home star. The brightness is 150 times less than the brightness of the Sun. Stars with such low mass are very interesting objects. Physical conditions in their depths have much in common with those that flow inside giant planets like Jupiter. In addition, the matter of such stars should be in a rather exotic state. Moreover, there is an assumption that planets near such stars can even more often serve as the cradle of life than near stars of the solar type. However, until now it has been impossible to determine the true sizes of these small stars due to their low luminosity and the lack of sufficiently sensitive equipment.

The problem was solved using the VLT interferometer - VLTI, (VLT - Very Large Telescope). The highest accuracy of measurements was achieved using two 8.2-meter telescopes of the Paranal Observatory (ESA), separated by 102.4 m from each other. An international team of astronomers from the Geneva Observatory (Switzerland) analyzed the data using a new software, for the first time obtained the exact size of small Proxima, the angular diameter of which turned out to be equal to 1.02 ± 0.08 milliseconds of arc, which corresponds to the size of an astronaut on the surface of the Moon as observed from Earth (or the head of a pin on the surface of the Earth as observed from the International space station). The human eye can distinguish objects separated by only 50 arcseconds or more. Three other dwarf stars were also measured, and the results are in agreement with generally accepted stellar theory, showing that our understanding of the structure and composition of such stars is close to the truth. The VLTI will soon be used to study very tiny stellar objects like “brown dwarfs.” Moreover, astronomers hope that it will be possible to directly observe exoplanets in other star systems (until now, all such objects have been discovered only using indirect methods).

Proxima Centauri lies on the border between real stars, brown dwarfs and planets. The mass and diameter of Proxima Centauri are about 1/7 the mass and diameter of the Sun. This star is 150 times more massive than Jupiter, but only 1.5 times larger. If its mass were still two times smaller, it would never be able to become a star; the hydrogen in its depths simply would not be able to ignite. Then it would be a "brown dwarf" and not a star.

For a star like the Sun, whose matter behaves like an ideal gas, stellar size is proportional to mass. However, for stars such as Proxima Centauri, quantum effects become extremely important, and their stellar matter “degenerates”; it itself is forced to resist compression, since nuclear reactions I can no longer do this. Objects with half the mass of Proxima Centauri or lighter have completely degenerate matter, and their size is independent of mass.

Noting. All text explanations for the illustrations given in the article are given in a tooltip when you hover the cursor over the image (for browser versions IE4 and higher).

Authorship, source and publication: 1. Prepared by the Astrogalaxy project based on materials from the magazine “Universe, Space, Time” No. 4, 2005 2. Source of information: ESA Press Release Space/light Now 3. Publication of the project 04/30/2005

« Constellation Alpha Centauri located in the southern hemisphere. Constellation Alpha Centauri is one of the largest constellations in our sky. By appearance Constellation Alpha Centauri resembles half man and half horse, that is, a centaur from Greek mythology. According to different sources, Constellation Alpha Centauri represents different centaurs, but speaks more for the fact that it is Chiron, who raised the heroes: Hercules, Peleus, Achilles, Theseus and Perseus.”

Mythology Constellation Alpha Centauri

Origins mythology Constellation Alpha Centauri they go to the constellation that the Babylonians called the buffalo man. They depicted him either as a four-legged bison with the head of a man, or as a creature with a human head and torso, but on hind legs bison or bull. The Babylonians associated this creature with the sun god Utu (Shamash).

IN ancient Greece and Rome, the constellation Centaurus was associated with the centaur Chiron, as discussed above. Chiron was the son of the Titan King Kronos and the sea nymph Philyra. Cronus seduced the nymph, but his wife Rhea suddenly appeared. In order not to be caught, Kron turned into a horse, as a result of which Philyra gave birth to a centaur - Chiron.

Chiron was a well-known and respected teacher of medicine, music and the art of hunting. He lived in a cave on Mount Pelion and trained many young princes and future heroes. Chiron died tragically when he accidentally hit one of Hercules' arrows dipped in Hydra's blood, a poison for which there is no antidote. Being the son of the immortal Kronos, Chiron was also immortal. When the arrow hit him, he suffered terrible pain, but could not die. Zeus eventually freed the centaur from immortality and suffering, allowed him to die, and then placed him among the stars.

Alpha Centauri

Alpha Centauri is the closest star system to the Sun, and is located at a distance of only 4.37 light years or 1.34 parsecs from Earth.

Alpha Centauri is the brightest star in the constellation Centaurus, it is the third brightest star in the sky, slightly brighter only than Arcturus in the constellation Bootes and Vega in the constellation Lyra.

Alpha Centauri is a binary star system consisting of Alpha Centauri A and Alpha Centauri B. They are sometimes called Alpha Centauri AB. The system's combined apparent magnitude is -0.27, making it the brightest star visible from Earth other than Sirius (-1.46) in the constellation Canis Major and Canopus (-0.72) in Kiel.

Components Alpha Centauri A and B form a visual binary star, meaning that they appear as a single star visible to the naked eye and cannot be seen individually without binoculars or a telescope. Although it doesn't take much magnification to "separate" these objects. Perhaps there is a third component in this star system, Alpha Centauri C (Proxima Centauri), which is believed to be associated with a binary star, but is located at an angle of 2.2° southwest of Alpha Centauri AB, a distance significantly greater than that between stars A and B.

Centauri

Average life expectancy Centauri is 700 Earth years. Just like people Centauri are humanoids. Their appearance type is Nordic. These blondes are believed to be descendants of the Lyrans, and come from a planet orbiting Alpha Centauri. These aliens are similar to the terrestrial Scandinavians, but there are significant differences in physiology. Metabolism Centauri faster than humans, so their body recovers in a shorter time. The electrical activity of the brain is such that a person would experience seizures under such a load. The blood composition and blood pressure are also different. The blood is thicker, since on its home planet Centauri gravity is stronger than on Earth. For the same reason, representatives of this race are physically stronger than people. Centauri Oxygen starvation is of little concern, and they practically never have fractures.

Centauri are quite strong telepaths - they can read and transmit thoughts, communicate through telepathy even with those who do not have such an ability. These creatures are also quite good at erasing memories.

One of the important discoveries in genetics Centauri a gene responsible for telepathic abilities was discovered. These humanoids do not actively work in the field of genetics, but use this discovery to determine the level of telepathic abilities of their newborns.

Like the Pleiadians, guests from Alpha Centauri they want to help humanity grow spiritually, although they play a smaller role on Earth than representatives of other races. During its development Centauri learned to live in harmony with nature, therefore representatives of this race are calm and confident.

At this stage of development, this race has mastered terraforming and biology well. In terms of technical progress, they have reached heights, and one can assume that in the future they will follow the path of harmonious fusion with nature and will explore more and more new worlds.

Centauri are working on organic technologies, wanting to create organisms that could fly in outer space, rather than using technology.

Belief Centauri synthetic, they have no saints and angels, the Absolute is not personified. They try to protect all living things.

We view this star system as one star, but in reality it is 3 stars. Of the 3, Proxima Centauri is closer to our Sun than any other famous star.

The Alpha Centauri system is the closest star system to our Sun. On the dome of our sky we see this multiple system as one star - the third most bright star, visible from Earth.

The Alpha Centauri system probably consists of three stars. Alpha Centauri is part of a binary or triple star system. The two main components are Alpha Centauri A and Alpha Centauri B. The third star, a red dwarf, Proxima Centauri is located 4.22 light years away and is our Sun's closest neighbor among stars.

Comparison of the sizes and colors of stars in the Alpha Centauri system with our Sun

If you look through a small telescope at the Alpha Centauri system, you will see the two main stars, but you will not see Proxima Centauri. It is too faint and too far away (4 full Moon diameters) to be easily recognized as part of the system.

To the eye, Alpha Centauri A appears as the fourth - brightest star visible from Earth, slightly eclipsed by Arcturus. However, the combined light of Alpha Centauri A and B is slightly brighter than Arcturus, making it the third brightest star visible in the sky from Earth. These stars are on average 4.3 light years away.

Yellow Alpha Centauri A is the same star type as our Sun (G2), although slightly larger. It appears bright in our sky due to its proximity to Earth. Just a few degrees away, the star Hadar (a separate star sometimes called Beta Centauri, not to be confused with Alpha Centauri B) appears dimmer in our sky than Alpha Centauri. But in fact, much further, 525 light years.

The surface temperature of Alpha Centauri A is several degrees lower than that of our Sun (that is, about 5770 K), but its larger diameter(about 25% more than the Sun) and total large area surfaces give it a brightness of almost 1.6 times our star.

The smaller member of the system, Alpha Centauri B, is slightly smaller than our sun, with a spectral type of K2. At a lower temperature (about 5300 K), Alpha Centauri B itself would be the 21st brightest star in our sky.

Hubble Space Telescope image of Proxima Centauri, the Sun's closest known star

Proxima is the closest of the three Alpha Centauri stars to Earth.

Faint red Proxima Centauri is almost a light year away from Alpha Centauri A and B. This long distance casts doubt on its status as part of a triple star system. In other words, there is some debate about whether Proxima is actually connected to the other two stars in the system. For now, her status is unclear. The star may just be passing nearby, but not part of the system. However, most astronomers say that Alpha Centauri is the closest star system to our Solar System, with the assumption that Proxima is a true part of the Alpha Centauri system.

Let's look at Proxima's distance from the other two stars in the Alpha Centauri system in a different way. Proxima's orbit around the two primary stars is thought to take half a billion years. Moreover, Proxima Centauri is an insignificant star. It is a red dwarf star with only one-eighth the mass of our Sun. If Proxima replaces the Sun in our solar system, it will only shine as bright as 45 full moons. Meanwhile, our sun is 400,000 times brighter than the full moon.

Proxima is also a flare star, subject to sudden changes in brightness. However, her flashes are really weak. On a bright star they would not be noticeable. So let's assume, as most astronomers do, that Proxima is part of the Alpha Centauri system, just a very strange, small and distant part.

And whether it is gravitationally bound to Alpha Centauri A or B or not, Proxima is still the closest known star to our Earth and Sun. It is about a trillion kilometers closer than the other two stars in the Alpha Centauri system, for example.

You can see Alpha Centauri using the Southern Cross as a guide. A line drawn across the crossbar to the east comes first to Hadar (Beta Centauri), then to Alpha Centauri

How to see Alpha Centauri. Unfortunately for us in the Northern Hemisphere, Alpha Centauri is located very far south in the dome of the sky. Most Russians don't see it. The cutoff latitude is around 29 degrees north, and anyone north of that is out of luck, the star never rises more than a few degrees above the southern horizon.

Meanwhile, in Australia and much of the southern hemisphere, Alpha Centauri is circumpolar, meaning it never sets. She is probably the most famous star that almost no one in the northern hemisphere has ever seen.

For northern observers, there really are no good pointer stars for Alpha Centauri. When the bright star Arcturus is high overhead, Alpha Centauri may be low in the southern sky if you are south of 29 degrees north latitude.

History and mythology of Alpha Centauri. The Alpha Centauri system appears to the eye as a single bright star, the brightest star in the southern constellation Centauri Centauri. Two alternative names for this star, Toliman and Bungula, are rarely used. The conclusions are somewhat dubious, but Toliman may be from Arabic word denoting ostriches, and Bungula apparently comes from the Latin - hoof.

Thousands of years ago, a movement of the Earth called precession—which is what causes the North Star to change over time—caused Alpha Centauri to appear higher in the sky, for the Northern Hemisphere, than it is now.

Classical mythmakers did not spend much time on this constellation, although it was believed to represent the wise centaurs who featured in the mythology of Hercules and Jason. The centaur was accidentally wounded by Hercules and placed in the sky after the death of Zeus.

Alpha Centauri itself means the right front hoof of a centaur, although little is known about its mythological significance, if any. The ancient Egyptians revered him and may have built temples according to his ascendant. In southern China, it was part of a star group known as the Southern Gate.

Astronomers determined the distance to the Alpha Centauri system for the first time in 1839, just a few months after they first determined the distance to the star (61 Cygni). The Alpha Centauri system is the closest star system to our Sun. In the dome of our sky, we see this multiple system as a single star—the third brightest star visible from Earth.

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