The most famous stars in the sky. The brightest stars seen from earth. Apparent stellar magnitude - what is it
The science
The night sky is full objects of incredible beauty which can be seen even with the naked eye. If you do not have special equipment to look at the sky - it does not matter, some amazing things can be seen without it.
Spectacular comets, bright planets, distant nebulae, twinkling stars and constellations can all be found in the night sky.
The only important thing to remember about light pollution in big cities. In the city, the light from the lanterns and windows of buildings is so strong that all the most interesting things in the night sky turns out to be hidden, therefore, to see these amazing things, you should go out of town.
light pollution
brightest planet
Very hot neighbor of the Earth - Venus can rightfully be proud of the title the brightest planet in the sky. The brightness of the planet is due to highly reflective clouds, as well as the fact that it is close to the Earth. Venus approximately 6 times brighter than other neighbors of the Earth - Mars and Jupiter.
Venus is brighter than any other object in the night sky, with the exception of the Moon, of course. Its maximum visible value is around 5. For comparison: the apparent magnitude of the full moon is -13 , that is, it is approximately 1600 times brighter than Venus.
In February 2012, a unique conjunction of three of the brightest objects in the night sky was observed: Venus, Jupiter and Moon which could be seen just after sunset.
The largest star
The largest star known to science - VY Canis Major, a type M red hypergiant, which is located at a distance of approximately 3800 light years from Earth in the constellation Canis Major.
Scientists have estimated that VY Canis Majoris could be more than 2100 times the size of the Sun. If it is placed in the solar system, then the edges of this monster will be located approximately in the orbit of Saturn.
The surface of a hypergiant can hardly be called noticeably outlined, since this star is approximately 1000 times less dense than our planet's atmosphere at sea level.
VY Canis Major is the source a lot of controversy in the scientific world, since the assessment of its size goes beyond the boundaries of the current stellar theory. Astronomers believe that the star VY Canis Majoris during the next 100 thousand years explode and die, turning into a "hypernova" and releasing an enormous amount of energy, and this energy will be more than any other supernova.
brightest star
In 1997, astronomers using NASA's Hubble Space Telescope found that the brightest known star is a star at a distance 25 thousand light years from us. This star highlights 10 million times more energy than the sun. In size, this star is also much larger than our star. If you place it in the center of the solar system, it will take the orbit of the Earth.
Scientists have suggested that this large star, located in the region of the constellation Sagittarius, creates a cloud of gas around it, which is called Nebula "Pistol". Thanks to this nebula, the star also received the name Pistol Star.
Unfortunately, this amazing star is not visible from Earth due to the fact that it is hidden by the dust clouds of the Milky Way. The brightest star in the night sky can you name a star? Sirius located in the constellation Canis Major. The magnitude of Sirius is -1,44.
You can observe Sirius from anywhere on Earth, except for the northern regions. The brightness of a star is explained not only by its high luminosity, but at a relatively close distance. Sirius is located approximately at 8.6 light years from the solar system.
The most beautiful star in the sky
Many stars are known for their brilliance of different colors, for example, a system consisting of blue and orange stars. Albireo, or bright red giant star Antares. However, the most beautiful of all the stars visible to the naked eye can be called a red-orange star. Mu Cephei, which is also called "Herschel's garnet star" after its first explorer, the British astronomer William Herschel.
The red giant Mu Cephei is located in the constellation Cepheus. This pulsating variable star and its maximum brightness changes 3.7 to 5.0. The color of the star also changes. Most of the time, Mu Cephei is a rich orange-red, but sometimes it takes on a strange purple hue.
Although Mu Cephei is a little dim, its reddish tint can be seen even with the naked eye, and if you take a simple binoculars, the spectacle will be more impressive.
The most distant space object
The farthest object visible to the naked eye is andromeda galaxy, which includes about 400 billion stars and which was noticed back in the 10th century by the ancient Persian astronomer Al Sufi. He described this object as "a small cloud".
Even if armed with binoculars or an amateur telescope, Andromeda will still look like slightly elongated blurry spot. But still, it is very impressive, especially if you know that the light from it gets to us. for 2.5 million years!
By the way, the Andromeda galaxy is approaching our Milky Way galaxy. Astronomers have estimated that these two galaxies will collide at about in 4 billion years, and Andromeda will be visible as a bright disk in the night sky. However, it is not yet known whether those who wish to look at the sky will remain on Earth after so many years.
> > The brightest star in the sky
Sirius is the brightest star: the meaning of the name Alpha Canis Major, characteristics and description with a photo, distance from the Earth, detection, a list of the brightest stars.
Among all the stars known to us, the brightest in the sky is Sirius, which is also called the “Star of the Dog”. The official name is Alpha Canis Major, located in the constellation of the same name.
Sirius is a binary system with a main sequence (A) star whose apparent magnitude reaches -1.46. It is 8.7 light years away from us and is closest to Earth.
In 1844, Friedrich Bessel noticed that the orbital path of Sirius A is a bit like a wave, which means there may be a weak satellite nearby. Alvan Clark confirmed this in 1862. We are talking about Sirius B - a white dwarf that can be seen in a large telescope (it has little effect on the overall brightness of the system).
But there are other stars near us, why is Sirius the brightest? The fact is that most stars belong to the category of red dwarfs. They are not only small, but also dull. In fact, the closest red dwarf is Proxima Centauri. It is M-type, smaller than G-type (Sun). The brightest is A-type (Sirius).
The starry sky can captivate for life thanks to its bright lights. Even with the naked eye, you can see that some objects shine brighter than others. Scientists measure the brightness of celestial bodies using a scale. The smaller the object itself, the brighter it will be.
List of brightest stars in the sky
We know which star is the brightest for an earthly observer. However, other bright celestial bodies can be found in space. You will be able to admire the brightest stars in the sky and their "apparent magnitudes" (as they are seen towards the Earth). Use our online star chart to find them yourself with a telescope.
Achernar
The star Achernar is located in the constellation Eridani and is 69 light years away from us. The apparent value is 0.46, and the absolute value is -1.3.
Procyon is located 11.4 light years in the constellation Canis Minor. The apparent value is 0.38, while the absolute value is 2.6.
Rigel is located 1400 light years away in the constellation of Orion. The apparent value is 0.12, and the absolute value reaches -8.1.
The chapel is located in the constellation Auriga (41 light years). The apparent magnitude is 0.08, and the absolute value is 0.4.
The star Vega is located in the constellation Lyra (25 light years). The apparent value is 0.03, and the absolute value is 0.6.
Arcturus is in the constellation Bootes (34 light years). The apparent value is -0.04, and the absolute value is 0.2.
Alpha Centauri is the third brightest in the entire sky. It is located in the Alpha Centauri system and is 4.3 light years distant. The apparent value reaches -0.27, and the absolute value - 4.4.
The star Canopus is located in the constellation Carina (74 light years). The apparent value is -0.72, and the absolute value reaches -2.5.
Lives in the constellation Canis Major. It is 8.6 light years away from us. The apparent value is -1.46, and the absolute value is 1.4.
The sun is the closest star to us, 93 million miles away. The apparent magnitude is -26.72, and the absolute value is 4.2.
If you ask any random person, then almost everyone will answer - "". This star is without a doubt the brightest and most popular, which is why most people think that she is popular because she is the brightest. However, it is not. Polaris takes only 42nd place in brightness among the stars of the night sky.
Stars have different brightness and color. Each star has its own, to which it is attached from the moment of birth. In the formation of any star, the dominant element is hydrogen - the most abundant element in the universe - and its fate is determined only by its mass. Stars with a mass of 8% of the mass of the Sun can ignite a nuclear fusion reaction in the core, fusing helium from hydrogen, and their energy gradually moves from the inside out and pours out into the Universe. Stars of low mass, due to low temperatures, are red, dim, and burn their fuel slowly - the longest-lived ones are destined to burn for trillions of years. But the more a star gains mass, the hotter its core, and the larger the region in which nuclear fusion takes place. Not surprisingly, the most massive and hottest stars are also the brightest. The most massive and hottest stars can be tens of thousands of times brighter than the Sun!
What is the brightest star in the sky?
This is not as simple a question as it seems. It all depends on what you mean by the brightest star.
Speaking of the brightest star in the sky that we see- that's one thing. And if by brightness we mean the amount of light emitted by a star, then this is completely different. One star in the sky can be brighter than another simply because it is closer than the larger, brighter stars.
When they talk about the brightest star in the sky
When talking about the brightest star in the sky, it is necessary to distinguish between the apparent and absolute brightness of the stars. They are usually called the apparent and absolute stellar magnitudes, respectively.
- Apparent magnitude is the brightness of a star in the night sky as viewed from Earth.
- The absolute magnitude is the brightness of a star from a distance of 10 parsecs.
The smaller the magnitude, the brighter the star.
is the brightest star in the night sky
The brightest star in the sky is undoubtedly Sirius. It shines and is highly visible in the Northern Hemisphere during the winter months. The apparent stellar magnitude of Sirius is -1.46 m. Sirius is 20 times brighter than the Sun and twice as massive as it. The star is located approximately 8.6 light years from the Sun and is one of the stars closest to us. Its brilliance is the result of its true brightness and its proximity to us. 
Sirius is a double star, the brightest star in the night sky, which is part of the constellation Canis Major, is also called α Canis Major. A binary star is a system of two gravitationally bound stars circulating in closed orbits around a common center of mass. The second star, Sirius B, has a magnitude of 8.4, is slightly lighter than the Sun, and is the first, and also the most massive, discovered to date. The average distance between these stars is about 20 AU. e., which is comparable to the distance from the Sun to Uranus. The age of Sirius (according to calculations) is approximately 230 million years.
Sirius A will exist on the main sequence for about 660 million more years, after which it will turn into a red giant, and then shed its outer shell and become a white dwarf. Therefore, the estimated duration of the life cycle of Sirius A can be about 1 billion years.
List of brightest stars
Distance: 0.0000158 light years
Apparent magnitude: −26,72
Absolute magnitude: 4,8
Sirius (α Canis Major)
Distance: 8.6 light years
Apparent magnitude: −1,46
Absolute magnitude: 1,4
Canopus (α Carinae)
Distance: 310 light years
Apparent magnitude: −0,72
Absolute magnitude: −5,53
Toliman (α Centauri)
Distance: 4.3 light years
Apparent magnitude: −0,27
Absolute magnitude: 4,06
Arcturus (α Bootes)
Distance: 36.7 light years
Apparent magnitude: −0,05
Absolute magnitude: −0,3
For the first time, the stars began to be distinguished by brightness in the II century BC by the ancient Greek astronomer Hipparchus. He singled out 6 degrees in the glow and introduced the concept of magnitude. The German astronomer Johann Bayer at the beginning of the 17th century introduced the brightness of the stars in the constellations with the letters of the alphabet. The brightest luminaries for the human eye were called α of such and such a constellation, β - the next in brightness, etc.
The hotter the star, the more light it emits.
Blue stars are the most luminous. Less bright whites. Yellow stars have an average luminosity, and red giants are considered the dimmest. The luminosity of a celestial body is a variable value. For example, in, dated July 4, 1054, it tells about a star in the constellation Taurus so bright that it was visible even during the day. Over time, it began to fade, and after a year it could no longer be seen with the naked eye.
Now in the constellation of Taurus, you can observe the Crab Nebula - a trace after the explosion of a supernova. In the center of the nebula, astronomers have discovered a source of powerful radio emission - a pulsar. This is all that remains of the supernova explosion observed in 1054.
The brightest stars in the sky
The brightest stars in the Northern Hemisphere are Deneb in the constellation Cygnus and Rigel in the constellation Orion. They exceed the luminosity of the Sun by 72,500 and 55,000 times, respectively. They are at a distance of 1600 and 820 light years from Earth. Another bright star in the Northern Hemisphere - Betelgeuse - is also located in the constellation of Orion. It emits 22,000 times more light than the Sun.
Most of the brightest stars in the Northern Hemisphere can be observed in the constellation of Orion.
Sirius, in the constellation Canis Major, is the brightest star visible from Earth. It can be observed in the Southern Hemisphere. Sirius is only 22.5 times brighter than the Sun, but the distance to this star is small by cosmic standards - 8.6 light years. The polar star in the constellation Ursa Minor shines like 6000 Suns, but it is 780 light-years away from us, so it looks dimmer than close Sirius.
In the constellation Taurus is a star with the astronomical name UW CMa. You can only see it with a telescope. This blue star is distinguished by its gigantic density and small spherical magnitude. It shines 860,000 times brighter than the Sun. This unique celestial body is considered the brightest object in the observable part of the Universe.
What is the brightest star in the sky? This is not as simple a question as it seems. It depends on what is meant by the brightest star.
If we talk about the brightest star in the sky that we see, this is one thing.
And if by brightness we mean the amount of light that a star emits, this is completely different. Because the brightest star in the sky can be so bright simply because it is closer than the larger, brighter stars.
Therefore, when talking about the brightest star in the sky, it is necessary to distinguish between the apparent and absolute brightness of the stars. They are usually called the apparent and absolute stellar magnitudes, respectively.
Apparent stellar magnitude is the degree of brightness of a star in the night sky as viewed from Earth.
The absolute magnitude is the brightness of a star from a distance of 10 parsecs.
The smaller the magnitude, the brighter the star.
For example, the absolute (bolometric) magnitude of the Sun is +4.8m, and the apparent magnitude is −26.7m.
The brightest star in the sky
The brightest star in the sky Sirius is from the constellation Canis Major.
The apparent stellar magnitude of Sirius is -1.46 m.
The absolute magnitude of this brightest star in the sky is 1.4 m.
By the way, Sirius is a binary star that consists of a dim white dwarf (Sirius B), which is slightly lighter than the Sun, and a brighter star (Sirius A), which is twice as massive as our Sun. Look at the picture of Sirius taken by the Hubble Space Telescope. The huge bright star is Sirius A, and the tiny white dot to the lower left of the main star is Sirius B.
Due to the fact that Sirius is the brightest star in the sky, he occupies a prominent place in the ideas of many peoples about the structure of the celestial sphere.
Where is Sirius located?
Finding Sirius is pretty easy. It is best to do this in winter, since Sirius is not visible in summer. First we find the constellation of Orion with the famous "Orion's belt" of three stars. Then you need to face the constellation of Orion and find the brightest star below and to the left of it.
This map will help you: 
The brightest star in the northern hemisphere
The brightest star in the northern hemisphere of the sky- Arcturus. It is the brightest star in the constellation Bootes.
Although Arcturus is the brightest star in the Northern Hemisphere, it is the fourth brightest star in the sky.
The first three places are occupied by Sirius, Canopus and Alpha Centauri, which are located in the southern hemisphere of the sky.
Here it must be clarified that in our northern latitudes we also see part of the southern hemisphere of the celestial sphere. Therefore, in the middle latitudes, the brightest star in the sky, Sirius, is also visible, but it belongs to the Southern Hemisphere of the celestial sphere. The farther south, the more stars of the southern hemisphere are available to us, despite the fact that the stars of the northern hemisphere only sink, but do not completely disappear. And from the equator, you can simultaneously observe all the stars of the southern and northern hemispheres of the sky.
The brightest star in the universe
The brightest star in the universe is R136a1. The star is in the R136 cluster in the Tarantula Nebula, also known as NGC 2070.
R136a1 is a real giant among the stars. It belongs to the rare class of blue hypergiants. 
The red dot is a red dwarf star. The yellow circle is our Sun. Blue - "blue dwarf". And in the background - part of the circle of the star R136a1.
The radius of this star is equal to 36 radii of our Sun.
The mass of R136a1 is 265 solar masses.
The apparent magnitude of the brightest star in the universe is 12.77m, and the absolute magnitude of this giant is -12.5m.
And finally, the luminosity of the star R136a1 - it is equal to the luminosity of 8,700,000 Suns!
By the way, this brightest star in our sky is still inferior in size to the largest of the known stars - the star UY Shield.
The human eye hardly distinguishes stars up to 7 m in a completely black sky.
But, it is usually believed that we see stars up to 6 m, adjusted for artificial sky illumination and for the average visual acuity of observers.
The Tarantula Nebula is located in the Large Magellanic Cloud, which unfortunately is not visible from Russia. In addition, the star R136a1 is located at a distance of 165,000 light years, so it is not visible to the naked eye.
But, if someone turns out to be south of 20 ° north latitude with a telescope with a diameter of 150 mm, then he may well try to see this largest star in the Universe known to science today.
Here are its coordinates (epoch J2000):
Right Ascension: 05h 38m 42.43s
Declination: -69° 06′ 02.2″
Names of the brightest stars
Below are the names of the 20 brightest stars that we can see in the sky with the naked eye.The list of the brightest stars is given in descending order of apparent magnitude.
| № | Name | Dist., St. years | Magnitude m | Range. Class | celestial hemisphere | Visibility in Russia |
|
|---|---|---|---|---|---|---|---|
| visible | absolute | ||||||
| 0 | The sun | 0,0000158 | −26,72 | 4,8 | G2V | everywhere | |
| 1 | Sirius (α Great Dog) |
8,6 | −1,46 | 1,4 | A1Vm | Southern | except for the Far North |
| 2 | canopus (α carina) |
310 | −0,72 | −5,53 | A9II | Southern | not visible |
| 3 | Toliman (α Centauri) |
4,3 | −0,27 | 4,06 | G2V+K1V | Southern | not visible |
| 4 | Arcturus (α Bootes) |
34 | −0,04 | −0,3 | K1.5IIIp | Northern | everywhere |
| 5 | Vega (α Lyrae) |
25 | 0.03 (variable) | 0,6 | A0Va | Northern | everywhere |
| 6 | Chapel (α Aurigae) |
41 | 0,08 | −0,5 | G6III + G2III | Northern | everywhere |
| 7 | Rigel (β Orionis) |
~870 | 0.12 (variable) | −7 | B8Iae | Southern | everywhere |
| 8 | Procyon (α Small Dog) |
11,4 | 0,38 | 2,6 | F5IV-V | Northern | everywhere |
| 9 | Achernar (α Eridani) |
69 | 0,46 | −1,3 | B3Vnp | Southern | not visible |
| 10 | Betelgeuse (α Orionis) |
~530 | 0.50 (variable) | −5,14 | M2Iab | Northern | everywhere |
| 11 | Hadar (β Centauri) |
~400 | 0.61 (variable) | −4,4 | B1III | Southern | not visible |
| 12 | Altair (α Eagle) |
16 | 0,77 | 2,3 | A7Vn | Northern | everywhere |
| 13 | Acrux (α Southern Cross) |
~330 | 0,79 | −4,6 | B0.5Iv + B1Vn | Southern | not visible |
| 14 | Aldebaran (α Taurus) |
60 | 0.85 (variable) | −0,3 | K5III | Northern | everywhere |
| 15 | Antares (α Scorpio) |
~610 | 0.96 (variable) | −5,2 | M1.5Iab | Southern | |
| 16 | Spica (α Virgo) |
250 | 0.98 (variable) | −3,2 | B1V | Southern | except for the islands of the Arctic Ocean |
| 17 | Pollux (β Gemini) |
40 | 1,14 | 0,7 | K0IIIb | Northern | everywhere |
| 18 | Fomalhaut (α Southern Fish) |
22 | 1,16 | 2,0 | A3va | Southern | in the south, partly mid-latitudes |
| 19 | Mimosa (β Southern Cross) |
~290 | 1.25 (variable) | −4,7 | B0.5III | Southern | not visible |
| 20 | Deneb (α Cygnus) |
~1550 | 1,25 | −7,2 | A2Ia | Northern | everywhere |
