We have prepared the top of the biggest stars. It contains, for example, the hypergiant VY Canis Major and such a luminary as NML Cygnus. They are all much larger than our Sun.
5.VV Cephei A
The fifth position in our rating went to the binary star VV Cepheus A, which has a radius of 1050-1900 solar. It is located in the constellation Cepheus. The luminary itself is an Algol-type eclipsing variable. Such objects are characterized by the presence of a cooler star passing in front of a hotter one. So some of the light from the hotter object is eclipsed and the overall brilliance of the vapor is temporarily reduced. VV Cephei is located at a distance of 5 thousand light years from us. The binary star consists of VV Cephei A (a red hypergiant with a radius of 1050 solar) and VV Cephei B, which is a blue B0 main sequence star. It revolves around VV Cephei A in an elliptical orbit.
The red hypergiant has a mass of about 25–100 solar masses. VV Cepheus A is at least the seventh largest star known to science. It also holds the honorable second place when it comes to the Milky Way galaxy specifically. In general, such luminaries (meaning hypergiants) are considered the most powerful, heaviest and brightest of the supergiants. Moreover, they are extremely rare. As for the "companion", this star is ten times larger than our Sun in diameter, and the luminosity index is 100,000 times higher.
4.VY Big Dog
On the fourth position of the rating is VY Canis Major, which is located in the constellation Canis Major. Before us is a hypergiant. The distance from us to VY Canis Major is 3900 light years, so it is not a fact that humanity will ever be able to investigate this object in detail. If we talk about size, then the radius of the star is up to 1540 solar radii. There is another version, according to which we have an ordinary red supergiant, whose radius does not exceed 600 solar. In general, disputes about the size continue, although there is no doubt that we have a real "monster" in front of us. To imagine its size, let us give an example: if we imagine an aircraft with a speed of 4.5 thousand km / h, then it will take about 160 years for VY to fly around Canis Major.
With such monstrous dimensions, the mass of the star is only seventeen solar. This indicates the extremely low density of the star. Scientists believe that its explosion could occur within the next 100 thousand years. This threatens a cataclysm to the systems located nearby, but the Earth, according to scientists, will not be affected by this cataclysm.
3. WOH G64
And here is another red supergiant located in a neighboring galaxy called the Large Magellanic Cloud. The latter is an SBm-type dwarf galaxy and a companion of the Milky Way. The star WOH G64 is extremely distant from us - it is located at a distance of 163 thousand light years from the solar system. The lower limit of the star's radius is 1540 solar, the upper one - 1730. WOH G64 is probably not the largest star of all, but it firmly ranks first in terms of size when it comes to the luminaries of the Large Magellanic Cloud.
It was suggested that the luminosity of WOH G64 is 500 thousand solar with a mass 40 times greater than that of our star. Meanwhile, these data cannot be correlated with the low temperature of WOH G64, which is 3200 K. Subsequent observations showed that the luminosity of the star is reduced by dust and gas around it. Be that as it may, this star is huge: if it were placed in the center of our system, then the surface of WOH G64 would reach the orbit of Saturn - the sixth planet from the Sun.
The stellar wind led to the fact that the giant luminary lost up to a third of its entire mass. Within a few thousand years, it can turn into a supernova. The Earth, however, does not threaten anything: the star is located at an incredibly large distance from our planet.
2. UY Shield
UY Shita is a bright red supergiant of spectral type M4Ia. It is located in the constellation Shield. It is classified as a semi-regular variable star with an approximate pulsation period of 740 days. First of all, this star is interesting for its size, which allows it to gain a foothold in the second line of the rating of the largest stars. If we draw an analogy with our Sun, then the volume of the UY Shield is about 5 billion times larger. In this case, the radius of the star can be 1900 solar.
Assuming there is no light pollution, the UY of the Shield can be viewed using an ordinary small telescope or even binoculars. Is it a reddish star located 2 ° north of the naked-eye type-A star? Shield and 2 minutes arc northwest of the Eagle Nebula. And although when infrared radiation is taken into account, the brightness of the star exceeds the brightness of the Sun by 340 thousand times, this object "hides" behind a huge layer of dust and gas around it. UY Shield is also notable for being the fastest burning star. She loses an amount of mass equal to 5.8 10?5M?/year.
1. NML Swan
And the deserved first place in our rating rightfully goes to the red hypergiant NML Swan. It is located in the constellation Cygnus (northern hemisphere of the starry sky). Its radius can reach 2775 solar! However, there is also a lower limit - in this case, the figure is approximately 1640 solar radii. The distance to the star is 5, 3 thousand light years. The giant has a mass of 25-40 solar, and the luminosity exceeds that of our native star by 270 thousand times. NML Cygnus is distinguished by extremely large mass loss rates, which amount to 2 × 10 × 4 solar masses per year.
The star was discovered in 1965. Later it turned out that it contains silicon monoxide, carbon monoxide, hydrogen cyanide, carbon monosulfide, sulfur oxide, sulfur dioxide, hydrogen sulfide. However, the giant luminary continues to hide its secrets, and it will be possible to find answers to many questions only many years later.