The closest star to the sun. What is the name of the star closest to Earth? Second closest star to earth

The Sun's closest stellar neighbors are three stars in the Alpha Centauri system. The two main stars of Alpha Centauri, A and B, form a binary system. Its distance from Earth is on average 4.3 light years. The third star is (Alpha Centauri C). It is located 4.22 light years from Earth and is the closest star to the Sun.

A and B Centauri revolve around a common center of gravity every 80 years. The average distance between them is about 11 astronomical units (AU). That is, approximately the same as from the Sun to Uranus. Proxima Centauri is about one-fifth of a light year, or 13,000 AU, away from the other two stars. And this circumstance makes some astronomers wonder whether it should be considered part of the same system.

Proxima Centauri could pass through the system and leave its environs within a few million years. Or it can be gravitationally bound to a binary pair. If there is a connection, Proxima's orbital period around the other two stars in the system should be about 500,000 years.

Potentially habitable planet

That they had discovered an Earth-sized planet orbiting Proxima Centauri. The new world, known as Proxima B, is about 1.3 times more massive than Earth. This suggests that this exoplanet is a rocky world, the researchers say.

The planet is located in the habitable zone of the star. That is, at the correct distance for liquid water to exist on its surface. Proxima B is 7.5 million kilometers away from its star. And it makes one revolution in orbit every 11.2 Earth days. As a result, it is likely that the exoplanet is tidally locked. This means that it always faces the same side towards its star. Just like the Moon, which shows only one side to the Earth.

However, it is not yet clear whether Proxima B could be habitable based on data obtained from modern telescopes. Astronomers will have to create models and conduct comparative studies. If they want to understand how habitable this planet might be. This world needs a closer look from researchers who should look for signs of its atmosphere. If this atmosphere is present, does it allow liquid water to flow across the surface? The surface temperature of the planet also depends on the atmosphere. And it will undoubtedly play a role in assessing the characteristics of Proxima B’s suitability for life.

Proxima B

Since Proxima B is very close to its star, a red dwarf, the problems of modeling its properties are already occupying the minds of scientists. Firstly, the planet is so close to the star that, as mentioned above, it is most likely tidally locked to it. This means that one side of the planet always faces the star. Therefore, one side of the planet must be very warm. While the opposite side should be very cold. If the winds do not distribute heat evenly throughout the planet. This would make it difficult for life to exist.

The planet's close distance from the red dwarf also brings other problems. Red dwarfs are unstable stars. And when they are young, they have great stellar activity and emit charged particles that can provoke intense irradiation of nearby planets. According to 2017 research conducted by NASA's Space Flight Center. Goddard, some of this radiation could break down molecules in the planet's upper atmosphere and thin it over time.

To better understand the existence of life, scientists continue to study red dwarf stars. In November 2017, another planet was discovered in the habitable zone of a red dwarf. It is almost as close to Earth as Proxima B. The planet is named Ross 128B, and it orbits a red dwarf star. It appears to be a much quieter place than Proxima B. The research team said that learning more about its atmosphere will require a next-generation telescope. Such as the European Extremely Large Telescope (E-ELT), the Giant Magellan Telescope (GMT) and the Thirty Meter Telescope (TMT), which are expected to become operational in the 2020s. (The James Webb Space Telescope (JWST) will not be able to perform such a search because the planet does not cross the surface of its star.)

Double star

To the naked eye, the system's two main stars shine as one, making them the third brightest "star" in our night sky. Individual stars can be seen through a small telescope. This is one of the best binary systems that can be observed. Proxima Centauri is too weak to see without assistance. And in a telescope, it appears at a distance of about four full Moon diameters from the other two stars.

On its own, Alpha Centauri A, also known as Rigel Centaurus, is the third brightest star in the night sky. It is slightly fainter, by 0.02 magnitude, than Arcturus. It is a yellow star of the same type (G2) as the Sun. And she's about 25 percent bigger than him. Alpha Centauri B is an orange K2 star, slightly smaller than the Sun. Proxima Centauri is a red dwarf star seven times smaller than the Sun. And only one and a half times larger than Jupiter. All three stars are slightly older—about 4.85 billion years old—than the Sun, which is about 4.6 billion years old.

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The closest star to Earth- Sun. Explore a star beyond the solar system - bright Alpha Centauri and the 20 closest stars to Earth, with distances.

To catch your friends, you can ask them about the star closest to Earth. Most people immediately start talking about Betelgeuse or Sirius. But here lies the catch. Of course, the Sun is closest to the Earth (150 million km). But what celestial body, besides the Sun, is closest star to Earth?

Which star is closest to Earth?

Alpha Centauri is considered the closest star to Earth besides the Sun. It ranks third in brightness and lives only 4.37 light years away. But this is not a single object, but a triple system. First of all, we see a binary pair orbiting a common center of gravity every 80 years. Alpha Centauri A is brighter than the Sun, while Alpha Centauri B is slightly less bright. The third member of this system is Proxima Centauri. Remember this name, since it is the closest star to Earth (4.24 light years).

The Alpha Centauri system is located in the constellation Centaurus, which can only be seen from the southern hemisphere. But even there you won’t be able to see this star. The fact is that it is too weak and you will need a fairly powerful telescope. To give you an idea, it would have taken New Horizons 78,000 years to get to Proxima Centauri.

Proxima Centauri has been the closest star to Earth for 32,000 years and will remain in this position for another 33,000 years. In 26,700 years it will reduce the distance to 3.11 light years. After it, the closest star to Earth is Ross 248.

The closest star to Earth in the Northern Hemisphere

The closest star to Earth in the northern hemisphere is Barnard's Star, a red dwarf in the constellation Ophiuchus. But it is also dim and not visible to the naked eye. If we take only the stars that can be observed without the use of special equipment, then Sirius is the closest (8.6 light years). It is twice the size and mass of the Sun.

How are distances to stars measured?

Parallax is used to determine the distance to a star from Earth. What's the point? Extend your arm and place your finger in front of a distant object. Close your eyes one at a time and you will understand that the object seems to be moving. This is parallax.

It is necessary to calculate the distance to the star when our planet is in one of the orbits (in summer), and then wait 6 months until it is on the opposite side and measure again. Then we measure the angle in relation to another object. This scheme works for any object living within 100 light years.

There are 45 stars located at a distance of 17 light years from the system. There may be 200 billion in total in the galaxy. Some are so weak that they cannot be detected.

List of 20 stars closest to Earth

This list shows the nearest stars and star systems, as well as the distance from Earth in light years. Some of them have several stars, but are part of a specific system. So:

1. Alpha Centauri – 4.2;
2. Bernard's Star - 5.9;
3. Wolf 359 – 7.8;
4. Lalande 21185 – 8.3;
5. Sirius - 8.6;
6. Leithen 726-8 – 8.7;
7. Ross 154 – 9.7;
8. Ross 248 – 10.3;
9. Epsilon Eridani – 10.5;
10. Lecaille 9352 – 10.7;
11. Ross 128 – 10.9;
12. EZ Aquarius – 11.3;
13. Procyon – 11.4;
14. 61 Cygnus – 11.4;
15. Struve 2398 – 11.5;
16. Groombridge 34 – 11.6;
17. Indian Epsilon – 11.8;
18. Dx Cancer – 11.8;
19. Tau Ceti – 11.9;
20. GJ 106 – 11.9.

According to NASA, there are another 45 stars that are within 17 light years of the Sun. Some are so small and dim that they are almost impossible to detect. Who knows, but maybe with improvements in technological capabilities, scientists will be able to find even closer star systems.

As banal as it may seem, the closest star to Earth is the Sun. Therefore, this formulation of the question is not very correct. Our yellow dwarf is no worse than other stars, and in general, it is one of the most common types of stars in the Galaxy. But we are not talking about our own luminary, so let’s consider which star is the closest to the Sun.

Many people know that the closest star to us is Alpha Centauri. A lot of science fiction has been written about this and this star is often mentioned as our neighbor. Yes, that’s right, this is the closest star to us besides the Sun. But everything is not as simple as it seems.

Alpha Centauri is also called Alpha Centauri by some meticulous people. Yes, this constellation is called in Latin as Centaurus, which means Centaur. But this is if we approach it quite formally. In general, this star is called Alpha Centauri everywhere. It just so happened, and that’s what it’s called in Russian-language literature, in reference books, in films, and indeed everywhere. Pedants love to argue about Centaur-Centaur, but this argument makes no sense.

The closest star to Earth is Alpha Centauri. The distance to it is 4.37 light years. This is exactly how long it takes light to travel the distance separating us at a speed of 300,000 km/s. So this proximity is relative, the distance is enormous, people will not soon be able to fly so far, if they can at all.

Alpha Centauri is not an ordinary star. This is a system of two stars, which are designated by the letters A and B. They rotate around a common center of mass every 80 years, and alternately one star is closer to us, then the other. Both stars are similar to the Sun, but component A is slightly brighter and component B is slightly fainter.

Both stars are visible as one to the naked eye, with a brightness of -0.27 m, and it is the third brightest star in Earth's sky.

But everything is even more complicated, and components A and B - Alpha Centauri - are not the closest stars to us at the moment. There is one more, third star in this system, which is called Proxima Centauri.

Proxima Centauri is the closest star to Earth

Proxima Centauri is a red dwarf star that is also part of the triple star system Alpha Centauri. But it is located very far from the two main and larger components of the system - 15,000 astronomical units, or 0.21 light years. By the way, this distance is only 20 times less than to Earth.

Due to its great distance from the center of the system, Proxima Centauri rotates in its orbit every 500 thousand years. At the moment, it is in the orbit in front of Alpha Centauri, so Proxima Centauri is the closest star to Earth for the next millennia. Then it will move to a distant part of the orbit and the nearest star will become Alpha Centauri, that is, its components A and B.

The closest star to Earth is Proxima Centauri, a red dwarf, one of the components of the triple system Alpha Centauri.

In the sky, Proxima Centauri is located 2.2 degrees from Alpha - like 4 lunar disks, but is not visible to the naked eye, its brightness is 11 m. Therefore, this closest star can only be found through a telescope, even a small one.

Although this star is our closest neighbor, it is very dim. It is 7 times smaller and lighter than the Sun. Even if it were observed directly from one of the planets of Alpha Centauri (if they exist there), then Proxima would still look like a dim 5th magnitude star in the sky.

If we were near the main stars of Alpha Centauri, then Proxima would look like a dim star (the reddish star is indicated by the arrow).

Proxima Centauri, by the way, has a planet in the habitable zone; its existence was confirmed by the European Southern Observatory in 2016. This planet is small in size and similar to Earth, located at a distance of 0.5 AU. from the star.

The closest star to Earth is Proxima Centauri. This is how it might look in the sky of one of its planets. Screenshot from the Space Engine universe simulator.

But whether life can exist there is a very controversial question. After all, Proxima Centauri is an unstable red dwarf that periodically flares up and the level of its radiation during these periods increases greatly, including in the X-ray range. Although in the oceans, if they exist there, life would be sufficiently protected, and in the course of evolution, life there could adapt to local conditions. The star is almost 5 billion years old, so anything is possible there.

Moreover, in 2019 there was a message that another planet was discovered near Proxima Centauri, at a distance of 1.5 AU. from the star. It is at least 6 times heavier than the Earth and has a temperature of only 39 K. But the existence of this planet still requires confirmation.

Proxima Centauri is also believed to have an asteroid belt. Some data indicate this, but this also still requires detailed study.

The stars closest to the Sun are our neighbors.

The closest stars to Earth in the past and future

The movement of stars, like the solar system itself, leads to a change in relative position, and the neighbors change. Proxima Centauri, and even the entire Alpha Centauri system, are only temporary neighbors. Gradually they will move away and other stars will become closest.

Proxima has been our closest star for the last 32 thousand years, and in another 33 thousand years the closest star will be Ross 248, which is located in the constellation Andromeda. Now it is quite far away - 10.3 light years, twice as far as Proxima Centauri is now.

Proxima Centauri.

Here's a classic catch-up question. Ask your friends, " Which one is closest to us?" and then watch them list nearest stars. Maybe Sirius? Alpha is there something there? Betelgeuse? The answer is obvious - this is; a massive ball of plasma located approximately 150 million kilometers from Earth. Let's clarify the question. Which star is closest to the Sun?

Nearest star

You've probably heard that the third brightest star in the sky is only 4.37 light years away. But Alpha Centauri not a single star, but a system of three stars. First, a double star (binary star) with a common center of gravity and an orbital period of 80 years. Alpha Centauri A is only slightly more massive and brighter than the Sun, and Alpha Centauri B is slightly less massive than the Sun. There is also a third component in this system, a dim red dwarf. Proxima Centauri.

Proxima Centauri- That's what it is the closest star to our Sun, located only 4.24 light years away.

Proxima Centauri.

Multiple star system Alpha Centauri located in the constellation Centaurus, which is visible only in the southern hemisphere. Unfortunately, even if you see this system, you will not be able to see Proxima Centauri. This star is so dim that you'll need a fairly powerful telescope to see it.

Let's find out the scale of how far Proxima Centauri from U.S. Think about . moves at a speed of almost 60,000 km/h, the fastest in. He covered this path in 2015 in 9 years. Traveling at such speed to get to Proxima Centauri, New Horizons will require 78,000 light years.

Proxima Centauri is the closest star over 32,000 light years, and it will hold this record for another 33,000 years. It will make its closest approach to the Sun in about 26,700 years, when the distance from this star to Earth will be only 3.11 light years. In 33,000 years, the nearest star will be Ross 248.

What about the northern hemisphere?

For those of us in the northern hemisphere, the closest visible star is Barnard's Star, another red dwarf in the constellation Ophiuchus. Unfortunately, like Proxima Centauri, Barnard's Star is too dim to be seen with the naked eye.

Barnard's Star.

Nearest star, which you can see with the naked eye in the northern hemisphere is Sirius (Alpha Canis Majoris). Sirius is twice the size and mass of the Sun, and is the brightest star in the sky. Located 8.6 light-years away in the constellation Canis Major, it is the most famous star that haunts Orion in the winter night sky.

How did astronomers measure the distance to stars?

They use a method called . Let's do a little experiment. Keep one arm extended and place your finger so that some distant object is nearby. Now open and close each eye one by one. Notice how your finger seems to jump back and forth as you look with different eyes. This is the parallax method.

Parallax.

To measure the distance to stars, you can measure the angle to the star with respect to when the Earth is on one side of the orbit, say in the summer, then 6 months later when the Earth moves to the opposite side of the orbit, and then measure the angle to the star compared to which some distant object. If the star is close to us, this angle can be measured and the distance calculated.

You can actually measure the distance this way to nearest stars, but this method only works up to 100,000 light years.

20 nearest stars

Here is a list of the 20 closest star systems and their distance in light years. Some of them have multiple stars, but they are part of the same system.

According to NASA, there are 45 stars within a radius of 17 light years from the Sun. There are more than 200 billion stars. Some are so faint that they are almost undetectable. Perhaps, with new technologies, scientists will find stars even closer to us.

Title of the article you read "Nearest star to the Sun".

The Sun is the basis of our system - the star closest to Earth, which, unlike all other objects, we clearly see on a clear day. At night, the remaining luminaries of the vast cosmos become available for observation. The number of stars filling the Universe is impossible to calculate. But scientists have identified and compiled a list of the closest celestial bodies located within a radius of 16. It included 57 star systems. Some of them are not single luminaries, but double and triple stars, so the total number of celestial bodies reaches 64. The list also included 13 brown dwarfs, which are noticeably inferior in mass to other objects.

We can consider only 7 stars from the list without the help of optical amplification - Alpha Centauri, Epsilon Eridani, Epsilon Indian, Tau Ceti, 61 Cygni. All of them have an apparent magnitude ranging from 1.43 to 6.03. Most of the luminaries belong to the spectral class M (red), their temperature is 2600-3800 K. Hot stars are Sirius A, spectral class A (white), 9940 K and Procyon A, class F (yellow-white), 6650 K. Brown The dwarfs included in the list belong to additional spectral classes L, T, Y. The list also includes 4 white dwarfs of class D, representing quite rare objects in the visible sector of the Galaxy.

Characteristics of Alpha Centauri - the closest star system to Earth

The shortest distance - 4.22 light years - separates our planet from, one of the three elements of the Alpha Centauri star system. In terms of its characteristics, the star closest to Earth (excluding the Sun) differs significantly from its neighbors. This star belongs to the spectral class M (red dwarf), and its mass and radius do not exceed 0.1 solar. Due to its low temperature - 3042 K - it emits little energy and is not detectable with the naked eye. It was opened in 1915. Periodic and active flares increase the luminosity of the star. Proxima Centauri and the rest of its home system are separated by a significant distance of 0.21 light years, so whether it is in its orbit has not been reliably determined. If it is proven that Proxima is circling around a binary star, then its total period exceeds 500 thousand years. Searches for possible exoplanets around the star were unsuccessful; scientists exclude the presence of large planets in its orbit.

The other two components of the system - Alpha Centauri A and Alpha Centauri B - closely interact with each other. From Earth they are observed as one star. The distance to the system is 4.36 light years. The objects are classified as spectral classes G and K - these are yellow and orange dwarfs. In terms of their characteristics and temperature, they are similar to the Sun, but older than it in age, which reaches 6 billion years. Component Centauri A is larger than its neighbor, with a mass of 1.1 and a diameter of 1.2 solar. The indicators of Centauri B are 0.9 and 0.86, respectively. The rotation of the luminaries occurs in an elliptical orbit, its inclination angle is 79.2 degrees, their period is 79.9 years.

Exoplanets Alpha Centauri

The search for planets included in the systems of stars closest to us is carried out regularly. Particular attention is paid to yellow and red dwarfs. To detect companions near distant objects, scientists have to measure the radial velocity of stars using spectrographs installed on powerful telescopes. The main studies were carried out by two independent groups: California and Geneva, which concentrated their attention on a limited number of objects. These included Alpha Centauri. European astronomers were able to achieve positive results. In 2012, analyzing a record amount of data, they reported a planet called Alpha Centauri B b. A clear signal appearing every 3.2 days indicated a body with a mass of 1.13 Earth's. The exoplanet is represented by a ball heated to 1200 degrees. This temperature is maintained due to the close location of the orbit to the surface of the star. Its year is a little more than three Earth days. It does not fall into the conventional zone where life could originate; its size in this case is 0.5-0.9 AU. e. from the luminary.

Further research and computer modeling give hope for the presence of a second, larger and more distant planet near Alpha Centauri B, with a rotation period of 20.4 days. According to hypothetical calculations, the influence of Centauri A will be felt once every 70 years. With the presence of oceans, its desert surface will become much more vulnerable.

Barnard's Star

The star, discovered by E. Barnard in 1916 and named after him, is classified as spectral class M. It is a red dwarf. Its location is the equatorial constellation Ophiuchus, at a distance of 5.96 light years from Earth. The small star is significantly inferior to our Sun, reaching 0.17 of its mass and diameter. The star cannot be detected with the naked eye, however, it is the fourth most distant from us. "Barnard's Flying" is famous for the agility of its own movement, which is directed towards our Sun. One day it will be closer to us than Proxima Centauri. Its speed is a record; it travels 10.36 arc seconds in a year.

Presence of planets

A California-based team of scientists has been making efforts for decades to discover planets around Barnard's star, but so far there is no evidence of their existence.

Luhmann 16

The constellation Vela, located in the Southern Hemisphere, is home to a binary system of brown dwarfs, the next most distant neighbors of the Sun. The distance to Luman 16 was 6.59 light years. The two elements of the system are almost identical, their mass is 0.4-0.5 solar. The rotation period is two decades. No other bodies have been discovered in the vicinity of this binary star system.

An Earth spaceship setting off on a journey to our closest neighbor, Proxima Centauri, will need 70 thousand years to reach it.

The distance between the components of the double star Alpha Centauri is 22 arcseconds. They merge when viewed with the naked eye, but are separated when observed even through a simple telescope. The angular distance between Centauri A and B is not constant. In 2010, it was 6.74 arcseconds, and by 2016 it will decrease to 4. The maximum value will be observed in 2056.

Among the stars close to us, only 3 are classified as luminaries of the first magnitude: Sirius, Alpha Centauri and Procyon, and the closest star to Earth is a red dwarf.