Which is more aldebaran or betelgeuse. The smallest and largest star in our galaxy
Astronomers never cease to delight us with new discoveries, finding more and more stars in the Universe. Some of them can be seen at night with the naked eye, just by looking at the night sky. Seeing others requires the most powerful telescopes. What is the largest star in the universe? Where is it located and how is it different from its neighbors? We invite you to familiarize yourself with the rating of the largest stars that have already been discovered by astronomers in the universe.
AH Scorpio
This is a real red giant, which is located in the region of the constellation Scorpio at a distance of 12 thousand light years from our planet. Its radius exceeds the radius of the Sun by 1.5 thousand times.
KY Swan
To this star, which is located in the constellation Cygnus, it will take as much as 5 thousand light years to fly from Earth. Comparing the radius of the planet with the Sun, we can say that its radius is equal to 1420 solar radii. But the mass of the planet is not so large - it is only 25 times heavier than our star. She could illuminate much more than the Sun, since the brightness of the KY Swan exceeds the solar one by many millions of times, so it can well win in the "Brightest" nomination.
VV Cephei A
This binary is located in the constellation of the same name, the distance to which is about 5,000 light years. She is recognized as one of the largest in her galaxy, second only to VY Big Dog. Estimating the radius along the equator of this star, we can say that it is equal to 1900 equatorial radii of our star.
VY Big dog
If we consider the Milky Way, then it was this star that became its record holder, with a radius exceeding the size of the Sun by more than 1540 times. According to astronomers' research, this star is very unstable and there is an assumption that within the next 100,000 years it will certainly explode, resulting in a gamma-ray burst that can destroy all life that is within 1-2 light years. As for the planet Earth, it can only be saved by the huge distance from our planet to VY Canis Major, which is about 4000 light years. Therefore, earthlings can be calm.
VX Sagittarius
Scientists note the pulsation of this variable star, as studies have shown periodic changes in its temperature and volume. And its pulsation can be compared with the beating of a human heart. The equatorial radius of VX Sagittarius is 1520 solar. The star is located in the constellation of the same name, from which it got its name.
Westerland 1-26
The numerical value of the radius of this giant exceeds the solar one by 1540 times. From Earth to Westerland 1-26 is about 11,500 light years.
WOH G64
The WOH G64 star is called the red star. It can be found by exploring the constellation Dora Fish, which is located in a galaxy called the Large Magellanic Cloud. Our solar system is about 163 thousand light years before it. Its radius is 1,730 times greater than that of the Sun. According to research, the star will cease to exist, becoming a supernova. However, this will not happen earlier than in 10-20 thousand years. Although during this time, a lot of things can change.
RW Cephei
This giant star is red and lies over 2,700 light-years from Earth. Its equatorial radius is 1636 times greater than that of the Sun.
NML Swan
The star acquired its name based on the name of the constellation, where it was discovered by astronomers. Its radius exceeds the solar one by 1650 times. A distance of 5300 light years separates us from NML Cygnus. Exploring the structure of the planet, scientists discovered sulfur oxide, hydrogen sulfide and other substances in it.
UY Shield
Scientists agreed that it is the UY Shield that is the largest in the entire universe. The record holder is located in the constellation of the same name at a distance of approximately 9.5 thousand light years from us. The star is very bright, but it is hampered by the huge amount of dust and gas around the planet.
The cosmos consists of many galaxies, some of which are so large that against their background our galaxy with the romantic name "Milky Way" seems miniature and tiny.
Galaxies, in turn, are composed of a large number of stars around which planets revolve. It is interesting that the name of these space objects, translated from the ancient Greek language, means "wanderer".
Consider these space wanderers, and find out what is the largest planet in the Universe.
Let's start with the planets of OUR Solar System
Mass: 317.8 Earth
Named after the Roman name for the God of Thunder, Jupiter is the largest planet in the solar system. Its diameter is many times the diameter of our Earth, and is equal to 139,822 kilometers. At this rate, Jupiter is the largest planet, and along with others, similar in composition, is classified as a gas giant.
On the picture: comparative sizes Jupiter and Earth
Jupiter has a strong magnetosphere and has many satellites of varying sizes. Today the planet has 69 satellites, but due to the great distance from the Earth, many of Jupiter's satellites may still go unnoticed.
The density of the planet is low, but the atmosphere of Jupiter, like the atmosphere of the Earth, consists of several layers, differing in composition and temperature.
Mass: 95 Earth
One of the most beautiful planets in the Universe, like Jupiter, belongs to the large planets of our solar system. First of all, it is famous for its gas rings, which can be seen even with a small telescope.
In the photo: the comparative sizes of Saturn and Earth
The main component of Saturn's atmosphere is hydrogen, but helium and ammonia are also present. IN upper layers the planet's atmosphere is raged by the strongest winds, the speed of which reaches 1,800 kilometers per hour.
It is also rich in companions revolving around it. There are 62 of them, and 12 of them have discovered spacecraft. In the solar system, only Jupiter has more satellites.
Interesting fact: A huge mystery to scientists is the storm raging at Saturn's pole. From space, it looks like a huge, regular hexagon.
Mass: 17.15 Earth
With a diameter of approximately 49,224 kilometers, Neptune is classified as a giant gas planet, and its orbit is farthest from the Sun.
In the photo: the comparative sizes of Neptune and Earth
Composed of solid rocks and ice, it is the heaviest planet in the solar system, 17 times the weight of the Earth. Stations sent to the far reaches of our galaxy have recorded the strongest winds on the planet, the speed of which reaches 600 meters per second.
Of the interesting things, we note that its orbit was first calculated by astronomers, and at the end of the 19th century it was possible to examine it through a telescope.
Mass: 14.53 Earth
Comparing volumes, Uranus is located on the third place in the solar system, and its diameter is 50,724 kilometers. But due to its low density, in terms of weight, it firmly established itself in fourth place in the list.
But what Uranus is leading in is that it is the coldest among all that revolve around the Sun. Its temperature is -225 degrees Celsius.
It also has small rings, but they are less visible than its neighbor in space orbit. In addition, this is the only planet that received its beautiful name in honor of the deity Ancient Greece, not Rome.
Weight: 59.726 · 10²³kg.
But to the question of which planet of the terrestrial group is the largest, astronomers answered in the early Middle Ages, conducting research on the parameters and characteristics of the Earth, Venus, Mars and Mercury.
The undisputed leadership in this group belongs to the Earth, which is very successfully located in the belt of life (Goldilocks zone). A little closer to the Sun and the water becomes steam, a little further, and the water freezes, making it impossible for life to arise. The mass of the Earth, as calculated by scientists, is equal to 0.00315 of the mass of Jupiter.
Earth is the only known planet in the universe today that has life. Many billions of years ago, the oceans formed on the surface of the planet, in the depths of which, according to scientists, life originated.
Venus is the sister of the Earth, since during the periods of their initial formation, these planets were very similar. Venus got its name in honor of the ancient Roman goddess of love and beauty. Two neighbors are similar in orbits and in structure. But in the atmosphere of Venus, carbon dioxide instead of oxygen, and the clouds are composed of toxic compounds.
Comparative sizes of the planets Earth and Venus
The first researchers observing the planet even saw clouds, and believed that it was constantly raining.
There is constant volcanic activity on Venus, so it is quite hot and not restless on its surface, because the temperature is 475 ° C. Moreover, the temperature difference on the planet's surface is minimal and is only a few degrees. This is due to the "greenhouse effect".
In the photo: the comparative sizes of Mars and Earth
The red planet was named after the god of war, and in its rocky surface it is similar to the Earth. But Mars is dry and lifeless, although hypotheses and theories have been repeatedly put forward that it is inhabited.
The temperature of a planet with a diameter of 6,780 kilometers fluctuates in different periods from -150 to +20 degrees Celsius. There are no poisonous gases on Mars, and the atmosphere is filled with carbon dioxide with small impurities of other substances.
Due to the absence of a magnetic field, its surface is constantly exposed to solar radiation. Mars has its own record indicators, because it is on its surface that there are two of the largest craters in the solar system.
In December 2017, NASA published amazing photos of the snow-covered surface of Mars. The temperature is so low at the poles of the planet that carbon dioxide in the atmosphere of Mars turns into a solid state and falls out in the form of snow on the surface.
And the last planet located closest to the Sun has the smallest diameter, equal to 4879 kilometers. It resembles a natural satellite of the earth, as on it, as on the moon, there are many craters, and the surface itself is rocky.
It is rather hot on Mercury, on the side facing the Sun, the temperature reaches +425 degrees, but at night it drops to -175.
Recent studies have shown that large ice formations sprinkled with ash and dust can be concentrated at the poles. This became possible because there are places at the poles where the sun's rays do not fall.
Now for the fun part! Let's talk about the largest exoplanets known to mankind.
Astronomers discover each year a large number of new exoplanets, new stars and worlds. Therefore, information about these distant objects is constantly changing. But let's try to collect all the available data on known planets at the beginning of 2018.
Mass: 0.49 masses of Jupiter
This huge planet orbits the star WASP-17, which is located in the constellation Scorpio and is 1307 light years distant from us.
The mass of WASP-17 b is about half that of Jupiter, but its radius is 2 times that of Jupiter. This indicates a low density of the planet, which is approximately equal to 10% of the density of water.
Surprising fact: this is the first exoplanet to rotate in the opposite direction from the rotation of its star.
Today, WASP-17 b is the largest planet known to humans in terms of volume.
51 Pegasus b
Mass: 0.45 masses of Jupiter
According to the latest data, it is a gas giant that orbits a parent star similar to our Sun. It is located at a distance of just over 50 light years from us.
51 Pegasus b makes a complete revolution around the parent star in just over 4 days. This is due to the proximity of the planet to the star, the radius of its orbit is 6 times less than the radius of Mercury and 19 times less than the radius of the Earth's orbit. Due to this proximity to the star, the temperature on the planet's surface must be very high.
With a mass of about 0.45 of the mass of Jupiter, 51 Pegasi b it is 1.9 times larger than itself big planet our solar system.
Mass: 0.76 masses of Jupiter
This planet was found in 1367 St. years from us, the star HAT-P-33, located in the constellation Gemini.
The planet has a mass of about 0.76 Jupiter masses, but its volume is 80% larger. The planet is very close to its star, it is about 20 times closer to it than the Earth is to the Sun. The surface temperature of HAT-P-33 b is likely to reach 1800ºC. The planet makes a complete revolution around the star in 83.4 hours.
Mass: 0.92 masses of Jupiter
Discovered in 2006, the exoplanet of the binary star system in the constellation Hercules has long been considered the largest known planet.
The star around which the planet orbits is 1,600 light-years from Earth. TrES-4 A b has a diameter that is 1.7 times that of Jupiter.
During the research, scientists have established that its density is very low, and it practically does not have a solid surface, and the temperature exceeds 1200 degrees Celsius.
Due to its low density and proximity to the parent star, the hot gas giant is constantly losing its atmosphere and is probably very similar to a huge comet, because it has a tail blown away from the star by the solar wind.
Mass: 1.39 masses of Jupiter
870 light years away is amazing planet, which is striking in its characteristics.
In its dimensions, WASP-12 b is 1.72 times larger than Jupiter, and its mass is 1.39 times that of Jupiter. But that's not what makes her unique.
The planet is in close proximity to its Sun-like parent star, WASP-12. The distance between the planet and the star is more than 18 times less than between the Sun and Jupiter. They are so close that they can exchange matter. Behind the planet is a huge plume of matter, which is captured by the gravity of the parent star. Most likely, this hot huge planet will collapse within the next 10 million years.
Interesting fact:
Mass: 8.5 Jupiter masses
This planet has aroused particular interest in the scientific community. When it was discovered, they were surprised that its mass exceeds the mass of Jupiter by almost 8.5 times. It is removed from the star at a distance of 330 astronomical units (1 AU is the average distance from the Sun to the Earth).
In an object of such a mass, thermonuclear reactions can begin, making the object a star, but apparently in the case of 1RXS J160929.1-210524 b mass was not enough to make a star out of a planet, and instead of a system of 2 stars, the world recognized a Star with an interesting planetary system.
Kepler-12 b
Mass: 0.43 masses of Jupiter
This is another gas giant that orbits its star at a very close distance (0.05 AU). It, like many similar planets, has a very high surface temperature (1481 ° K) and swells from the pressure of the solar wind.
Its mass and radius are 0.431 and 1.7 times the mass and radius of Jupiter, respectively.
Beta Painter b
Mass: 6 masses of Jupiter
We conclude our article with a planet with the beautiful name of Beta Painter b. It is located in the constellation of the Painter at 63 St. years from us. The planet's orbit is equal to 9 AU, which is almost 2 times the radius of Jupiter's orbit and is comparable to the orbit of Saturn.
The mass of this giant is 7 times that of Jupiter, and its radius is 1.65 times that of Jupiter.
Completion
In fact. there are still very, very many planets that we want to talk about. If you liked this article and want to continue, write about it in the comments, and we will definitely write something.
Not so long ago, the site already wrote about in the universe. You can sit down, this is a very entertaining article.
And below are a few more interesting facts about the planets.
Interesting facts about the planets
- Jupiter acts as a kind of shield, protecting the Earth from comets and other space objects that enter our system. He just attracts them due to his strong gravity.
- Jupiter and the fastest in revolution around its axis. If we consider the parameters of the earth, this happens in 12 hours.
- Our Earth is the only one that was not named after an ancient Greek or ancient Roman deity.
- The volcano Olympus, located on the surface of Mars, is the largest of its kind yet studied in space. Its summit is located at a distance of 27 kilometers from the reddish surface of Mars.
- Due to the fact that the orbit of Mercury is located almost perpendicular to the plane of rotation of our star, there should logically not be a change of seasons on it. But the planet's orbit is too elongated. Due to this, the planet either approaches the Sun to a distance of 46 million km, then moves away from it up to 70 million km. It is the removal of the planet from the Sun that forms the seasons on Mercury.
- On Earth, the seasons depend on the tilt of the planet's axis, and not on the planet's distance from the Sun. It turns out that in winter the Earth is at a closer distance to the Sun than in summer.
In conclusion, we note that our Galaxy, like neighboring, smaller ones, is a satellite of a large Galaxy. But at the same time, the process of absorption by the Milky Way of the Gnome-Sagittarius Galaxy, which was our satellite for millions of years, is taking place.
Many of the planets represented are known to Mankind since ancient times, and from the first moment of discovery they were objects of worship, religious beliefs, harmoniously entering the mythology, legends and religions of many peoples of the world.
Determining the largest star in the Universe, its size and mass has always been difficult for scientists. The angular dimensions of the stars are so small that even the largest telescopes cannot see stars in the form of round disks. Accordingly, the size of stars even with the largest telescope cannot be determined. Scientists have learned to determine the size of the most big stars based on the three most famous methods:
- Observing the eclipse of the satellite of the earth - the Moon, scientists have learned to determine angular dimension, and, knowing the distance to the object, you can determine its true, linear dimensions;
- The size of a star can be determined using special stellar optical interferometers. The principle of operation of these devices is based on the interference of starlight, which is reflected by a pair of widely spaced mirrors.
- The size of a star can also be calculated theoretically, based on estimates of the total luminosity and temperature of stars according to the Stefan – Boltzmann law. The luminosity of a star is related to the radius of the star by the formula L \u003d? T4 4? R2 or
This method allows you to find the radius of a star by its temperature and luminosity, since the parameters R, L and T are known.
What is a star?
Star - a luminous gas (plasma) celestial body formed from a gas-dusty environment, in which thermonuclear reactions take place.
The sun is a typical G2 dwarf star with a radius of 696 thousand km.
The largest star belongs to the class of red hypergiants, although difficulties in determining the exact sizes of most stars lead to the fact that it is not possible to say with great certainty which star is the largest in the universe.
Red hypergiants are stars in their very last stages of evolution. When the supply of hydrogen, used as a source of nuclear energy in the central part of the star's core, begins to deplete, a stage of internal changes begins, as a result of which the outer layers of the star expand greatly. The red hypergiant consists of a vast envelope of very rarefied gas that surrounds the star's central core.
Hypergiants - these are stars of huge sizes and masses, having a luminosity class 0 in the Hertzsprung-Russell diagram (the diagram shows the relationship between the absolute stellar magnitude, spectral class, luminosity, and temperature of the star's surface), hypergiant stars are defined as the most powerful, heaviest, brightest and at the same time the rarest and short-lived supergiants.
What is the largest star in the universe?
The equatorial radius of the Sun, 695,500 km, is used as a unit for measuring the radius of stars.
As mentioned above, the exact size order of the largest stars is difficult to determine. many large stars have extended atmospheres and opaque dust envelopes and disks, or even pulsate.
In the very first place in some of the largest stars in the universe is a star VY Big Dog (lat.VY Canis Majoris, VY CMa). The distance from Earth to the largest star in the universe, VY Canis Major, is approximately 5,000 light years. The radius of the star was determined in 2005 and is in the range of 1800-2100 solar radii. The mass of the largest star is ~ 15-25 solar masses.
The second largest stars in space belongs to a star WOH G64located in the Large Magellanic Cloud galaxy. The radius is 1738 solar radii.
In third place is a large star VV Cephei A, with a radius of 1600-1900 radii of Sonets.
In fourth place is the star Mu Cephei (? Cep /? Cephei), better known as "Herschel's garnet star" - is a red supergiant located in the constellation Cepheus. The radius of the star is 1650 times the radius of a star named the Sun.
The fifth place is taken by a star KY Swan- a star located in the constellation Cygnus at a distance of about 5153 light years from us. This is one of the largest stars known to science. The radius is 1420 solar radii. 
The ratio of the sizes of the planets of the solar system and some well-known stars, including VY Canis Major:
1.Mercury
5 Aldebaran
6 Betelgeuse
What is the heaviest (massive) star in the universe?
On June 21, 2010, astronomers led by Paul Crowter, professor of astrophysics at the University of Sheffield, while studying a huge number of star clusters, discovered a star whose mass is much greater than the mass of the Sun.
Scientists have discovered several stars with surface temperatures in excess of 40,000 degrees. It is more than seven times hotter than the temperature on the Sun and several million times brighter. Some of these stars were born with masses over 150 solar masses.
The heaviest star, named R136a1, is from cluster RMC 136a (better known as R136), a cluster of young, massive and hottest stars located inside the Tarantula Nebula in the Large Magellanic Cloud, 165,000 light-years from planet Earth. The R136a1 star is one of the most powerful stars in the universe, with a luminosity 10 million times that of the Sun. The mass of R136a1 is 265 solar masses and a radius of 67 solar radii.
What is the closest star to the solar system?
The closest star to Earth after the Sun is Proxima Centauri, which is 4.243 ± 0.002 light-years from Earth, which is 270,000 times the distance from Earth to the Sun star. The star Proxima Centauri is a red dwarf orbiting the Alpha Centauri system.
The mass of Proxima Centauri is 0.123 ± 0.006 solar masses, which is 7 times less than the mass of the Sun and 150 times more than the mass of the planet Jupiter. Age 4.85 × 109 years. Temperature 3042 ± 117 K. Radius 0.145 ± 0.011 solar radii, i.e. the actual diameter is 7 times less than the diameter of the Sun's star and only 1.5 times the diameter of the planet Jupiter.
What is the brightest star in the night sky?
Sirius is the brightest star in the sky, from the constellation Canis Major. The star Sirius can be observed from almost any region of the Earth, with the exception of only its northernmost regions. Sirius is one of the closest stars to us and is only 8.6 light-years away from the solar system. The brightness of Sirius is 23 times that of the Sun. Originally, Sirius consisted of two of the most powerful blue stars of spectral class A, now the age of this binary star is about 230 million years.
The brightest star in the universe is Pollux in the constellation Gemini. Although it is very difficult to determine the brightest star. Also in the list of the brightest stars stars compete: Shaula (constellation Scorpio); Gakrux (constellation of the Southern Cross); Castor (in the constellation Gemini). Star Pistol (English Pistol Star) is one of the most bright stars in our Galaxy. The luminosity of the star Pistol exceeds 1.7 million luminosities of the Sun, i.e. in 20 seconds the star Pistol emits as much light as the sun emits in a whole year.
The science
Of course, the oceans are immense and the mountains are incredibly high. Moreover, the 7 billion people for whom the Earth is home is also an incredibly large number. But living in this world with a diameter of 12,742 kilometers, it is easy to forget that this is, in fact, a trifle for such a thing as space. When we look into the night sky, we realize that we are just a grain of sand in a vast infinite universe. We invite you to learn about the largest objects in space, the size of some of them is difficult for us to imagine.
1) Jupiter
The largest planet in the solar system (142,984 kilometers in diameter)
Jupiter is the largest planet in our star system. Ancient astronomers named this planet after the father of the Roman gods, Jupiter. Jupiter is the fifth planet from the Sun. The planet's atmosphere is 84 percent hydrogen and 15 percent helium. Everything else is acetylene, ammonia, ethane, methane, phosphine, and water vapor.
Jupiter's mass is 318 times that of Earth, and its diameter is 11 times larger. The mass of this giant is 70 percent of the mass of all planets in the solar system. Jupiter's volume is large enough to accommodate 1,300 Earth-like planets. Jupiter has 63 known moons, but most of them are incredibly small and fuzzy.
2) Sun
The largest object in the solar system (1,391,980 kilometers in diameter)
Our Sun is a yellow dwarf star, the largest object in the star system in which we exist. The sun contains 99.8 percent of the mass of this entire system, most of the rest of the mass is Jupiter. Currently, the Sun is 70 percent hydrogen and 28 percent helium, the remaining matter is only 2 percent of its mass.
Over time, the hydrogen in the sun's core turns into helium. Conditions at the Sun's core, which is 25 percent of its diameter, are extreme. The temperature is 15.6 million Kelvin and the pressure is 250 billion atmospheres. The energy of the Sun is obtained through nuclear fusion reactions. Every second, approximately 700,000,000 tons of hydrogen is converted into 695,000,000 tons of helium and 5,000,000 tons of energy in the form of gamma rays.
3) Our solar system
15 * 10 12 kilometers in diameter
Our solar system contains only one star, which is the central object, and nine major planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto, as well as many satellites, millions of solid asteroids and billions of icy comets.
4) Star VY Canis Major
The largest star in the universe (3 billion kilometers in diameter)
VY Canis Majoris is the largest known star and one of the brightest stars in the sky. It is a red hypergiant located in the constellation Canis Major. The radius of this star is about 1800-2200 times greater than the radius of our Sun, and its diameter is about 3 billion kilometers.
If this star were placed in our solar system, it would cover the orbit of Saturn. Some astronomers believe that VY is actually smaller - about 600 times the size of the Sun, and therefore would only reach the orbit of Mars.
5) Huge deposits of water
Astronomers have discovered the largest and most massive reserves of water ever found in the universe. About 12 billion years old, the giant cloud contains 140 trillion times more water than all of Earth's oceans combined.
A cloud of gaseous water surrounds a supermassive black hole located 12 billion light-years from Earth. The discovery shows that water has predominated in the universe for almost all of its existence, the researchers said.
6) Extremely large and massive black holes
21 billion solar masses
Supermassive black holes are the largest black holes in the galaxy, with a mass of hundreds or even thousands of millions of solar masses. Most, and possibly all galaxies, including the Milky Way, according to scientists, contain supermassive black holes at their centers.
One such monster, which is 21 million times the mass of the Sun, is an egg-shaped funnel of stars in NGC 4889, the brightest galaxy in a sprawling cloud of thousands of galaxies. The hole is located about 336 million light-years from us in the constellation Coma Veronica. This black hole is so huge that it is 12 times the diameter of our solar system.
7) Milky Way
100-120 thousand light years in diameter
The Milky Way is a crossed spiral galaxy that contains 200-400 billion stars. Many planets revolve around each of these stars.
According to some estimates, 10 billion planets are in the habitable zone, revolving around their parent stars, that is, in zones where there are all conditions for the emergence of life, similar to the earth.
8) El Gordo
The largest cluster of galaxies (2 * 10 15 solar masses)
El Gordo is located over 7 billion light years from Earth, so what we are seeing today is just an early stage. According to the researchers who studied this galaxy cluster, it is the largest, hottest and emits the most radiation than any other known cluster at the same distance or further.
The central galaxy at the center of El Gordo is incredibly bright and has an unusual blue glow. The study authors suggest that this extreme galaxy is the result of a collision and merger of two galaxies.
Using the Spitzer Space Telescope and optical images, scientists estimate that 1 percent of the cluster's total mass is made up of stars, with the rest being hot gas that fills the space between stars. This ratio of stars to gas is similar to that of other massive clusters.
9) Our Universe
Size - 156 billion light years
Of course, no one could ever name the exact dimensions of the Universe, but, according to some estimates, its diameter is 1.5 * 10 24 kilometers. It is generally difficult for us to imagine that there is an end somewhere, because the Universe includes incredibly giant objects:
Earth diameter: 1.27 * 10 4 km
Sun diameter: 1.39 * 10 6 km
Solar system: 2.99 * 10 10 km or 0.0032 sv. l.
Distance from the Sun to the nearest star: 4.5 sv. l.
Milky Way: 1.51 * 10 18 km or 160,000 St. l.
Local group of galaxies: 3.1 * 10 19 km or 6.5 million sv. l.
Local supercluster: 1.2 * 10 21 km or 130 million sv. l.
10) Multiple
You can try to imagine not one, but many Universes that exist at the same time. The Multiple Universe (or Multiple Universe) is an admissible cluster of many possible Universes, including our own, which collectively encompass everything that exists or can exist: the integrity of space, time, material matter and energy, as well as the physical laws and constants that make it all describe.
However, the existence of other universes besides ours has not been proven, so it is highly likely that our universe is one of a kind.
My 6-year-old daughter is a question-asking machine. A couple of days ago, we were driving from school and she was asking me about nature. One of her questions was, " What is the largest star in the universe? "I gave a simple answer." The universe is a big place, "I said," and there is no way we can know which star is the biggest"But that's not the real answer.
Radius and mass of the Sun:
When it comes to the size of stars, it's important to first look at ours for a sense of scale. Our star has a diameter of 1.4 million kilometers. This is such a huge number that it is difficult to get an idea of \u200b\u200bthe scale. By the way, the Sun accounts for 99.9% of all matter in ours. In fact, you could fit a million within the volume of the sun.
Using these values, astronomers have created the concepts of "solar radius" and "solar mass", which they use to compare larger or smaller stars and masses with our Sun. The solar radius is 690,000 km, and the solar mass is 2 x 10 30 kg. This is 2 nonillion kilograms, or 2,000,000,000,000,000,000,000,000,000,000 kg.
An illustration of a Morgan-Keenan spectral diagram showing the difference between main sequence stars. Credit: Wikipedia Commons.
It is also worth considering the fact that our Sun is quite small, it is a G-class main sequence star (in particular, a G2V star), which is widely known as and is located on the smaller side of the size chart (see above). Although the Sun is definitely larger than the most common M-class stars, or red dwarfs, it is itself dwarf (no pun intended!) Compared to blue giants and other spectral types of stars.
Classification:
Stars are grouped based on their characteristics, such as spectral class (i.e. color), temperature, size, and brightness. The most common classification method is called the Morgan-Keenan (MK) system, which classifies stars based on temperature using the letters O, B, A, F, G, K, and M, where O are the hottest stars and M are the coldest. Each alphabetic class is subdivided into numerical subclasses from 0 (hottest) to 9 (coldest). That is, the hottest stars are O1, and the coldest stars are M9.
In the Morgan-Keenan system, the luminosity class is added using Roman numerals. This is done based on a certain width of absorption lines in the spectrum of the star, which vary with the density of the atmosphere, which distinguishes giant stars from dwarfs. The luminosity has classes 0 and I for hyper- and supergiants; classes II, III and IV for bright, normal giants and subgiants, respectively; class V for main sequence stars; and classes VI and VII apply to subdwarfs and dwarfs.
Hertzsprung-Russell diagram showing the relationship between star color, luminosity and temperature. Credit: astronomy.starrynight.com.
There is also a Hertzsprung-Russell diagram concerning the stellar classification by absolute stellar magnitude (i.e. true brightness), luminosity and surface temperature. The same classification is used for spectral types, ranging from blue and white at one end to red at the other, which then combines the stars in absolute magnitude, placing them on a two-dimensional plot (see above).
On average, Class O stars are hotter than stars of other classes, reaching effective temperatures up to 30,000 Kelvin. At the same time, they are larger and more massive, reaching sizes over 6.5 solar radii and up to 16 solar masses. At the lower end of the diagram, K- and M-class stars (orange and red dwarfs) are usually colder with temperatures between 2400 and 5700 Kelvin, which is 0.7 - 0.96 from and somewhere 0.08 - 0. 8 from the solar mass.
Based on the complete classification of our Sun (G2V), we can say that it is a main sequence star with a temperature of about 5800 Kelvin. Now consider another famous star system in our galaxy - Eta Carinae - a system containing at least two stars located at a distance of 7500 light-years from us in the direction of the constellation Carina. The main star of this system is estimated to be 250 times larger than the Sun, has a mass of at least 120 solar masses, and a million times brighter than the Sun, making it one of the largest and brightest starsever observed.
Eta Carinae, one of the most massive stars known, is located in the constellation Carinae. Credit: NASA
There is currently debate over the size of this star. Most stars emit stellar wind (the same as), losing mass over time. But This Kiel so large that it dumps 500 times more mass annually. With such a loss of mass, astronomers find it difficult to accurately measure where a star ends and the stellar wind begins. In addition, scientists believe that This Kiel will explode in the not so distant future, and it will be the most spectacular that people have ever seen.
In terms of net mass, first place goes to star R136a1located at a distance of 163,000 light years from us. It is believed that this star may contain 315 solar masses, which is a mystery to astronomers, since they believe that stars can contain a maximum of only 150 solar masses. The answer lies in the fact that star R136a1 formed, in all likelihood, when several massive stars merged together. Needless to say, R136a1 can explode any day like.
In terms of large stars, a good (and popular) example is Betelgeuse... Located in the shoulder of Orion, this famous supergiant has a radius of approximately 950-1200 solar radii, at such a radius the Sun would absorb in our Solar System... In fact, whenever we want to put the size of our Sun in perspective, we often use Betelgeuse for this (see below).
However, even after we use this clumsy red giant to compare the Sun to large stars, there are still larger stars. Consider star WOH G64, a red supergiant located in the Large Magellanic Cloud, approximately 168,000 light-years from Earth. With a diameter of 1540 solar radii, this star is currently the largest star known to us in the universe.
But there is also RW Cephei, an orange hypergiant in the constellation Cepheus, located 3500 light years from Earth and measuring 1535 solar radii in diameter. Star Westerland 1-26 (Westerlund 1-26) unusually large, it is a red supergiant (or hypergiant) located in the Westerlund 1 supercluster at a distance of 11,500 light-years from us and measuring 1,530 solar radii in diameter. Meanwhile, stars V354 Cepheus and VX Sagittarius also have a huge size of 1520 solar radii in diameter.
The biggest star of UY Shield (UY Scuti)
The title of the largest star in the universe (which we know of) comes down to two contenders. For example, UY Shield Currently at the top of the list, located 9,500 light years away in the constellation Shield, this bright red supergiant and pulsating variable star has an average radius of 1,708 solar radii - or 2.4 billion kilometers (15.9 AU) , thereby giving it a volume of 5 million solar volumes.
However, this average estimate includes an error of ± 192 solar radii, which means that the radius of this star can be either 1900 or 1516 solar radii. The bottom border places it on par with V354 Cepheus and VX Sagittarius... Meanwhile, the second largest star on the list of possible the largest stars - this is NML Cygni (NML Cygni), a semi-regular variable star red hypergiant, located in the constellation Cygnus, 5300 light-years from Earth.
An enlarged image of the red giant UY Shield. Credit: Rutherford Observatory / Haktarfone.
Due to the location of this star in, it is heavily shaded by dust. As a result, according to astronomers' calculations, its size could be from 1642 to 2775 solar radii, which means that it could become the largest star known in the universe (with a reserve of about 1000 solar radii), or in fact the second largest, keeping up with UY Shield.
Just a few years ago the title the biggest star worn by VY Big Dog (VY Canis Majoris), a red hypergiant in the constellation Big Dog, located 5,000 light years from Earth. Back in 2006, Professor Robert Humphrey of the University of Minnesota calculated the upper limit of its size at 1540 larger than the Sun. Its average mass, however, was 1,420 solar masses, which puts it in 8th place behind V354 Cepheus and VX Sagittarius.
The above were listed the biggest stars, which we know about, but there are probably dozens of larger stars hidden by dust and gas, so we cannot see them. But even if we cannot detect these stars, we can speculate on their likely size and mass. So how big can stars be? Once again, Professor Robert Humphrey from Minnesota gave the answer.
Comparison of the sizes of the Sun and VY of Canis Major, the star that once bore the title the largest known star in the universe... Credit: Wikipedia Commons / Oona Räisänen.
As she explained in her article, largest stars in the universe - the coldest. Therefore, although This Kiel is the brightest star we know of, it is extremely hot (25,000 Kelvin) and therefore only 250 solar radii in diameter. The largest starson the contrary, they will be cold supergiants. As in the case VY Big Dogwhich has a temperature of 3500 Kelvin, and a really large star will be even colder.
At 3000 Kelvin, Humphrey estimates that the cold supergiant would be 2,600 times the size of the Sun. This is below the upper bound of the estimates for NML Swan, but above average ratings as for NML Swanand for UY Shield... Hence, this is the upper limit of a star (at least in theory and based on all the information we have to date).
But as we continue to peer into the Universe with all our telescopes and explore it with robotic spacecraft and manned missions, you will surely find new amazing things that will amaze us further!
And be sure to check out this amazing animation below, which shows the sizes of various objects in space, from tiny to star UY Shield... Enjoy!
Title of the article you read "What is the largest star in the universe?".
