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How big are stars? Compare to Sun and Earth

how big are stars

If someone does not know about the approximate real size of stars and if they are asked by anyone “how big are the stars”? or “How big are the stars compared to the sun or earth”? Then he will say that if the stars appear very small in the sky, they are very small.

But is it true? No!

In reality, the stars that seem very small in the sky, are actually very large in size. Therefore to know how big the stars can be in the sky, read this article carefully.

How big are the stars?

You must have seen many stars in the sky. Some stars look small, and some look bigger. The stars we see as big as they actually are? Or maybe smaller or larger?

So the truth is that the stars are very big, I mean very-very big. Actually, there are many different types of stars. Some stars are small, some stars are very large. And some stars are so big that millions of small stars can fit into the larger ones. 

Our Sun is also a star whose size is about 700,000 km. And some stars are so big that even hundreds of suns can fit into them.

The name of the biggest star is “Stephenson 2-18”. Which is about 2160 times bigger than the Sun in diameter, whereas around 10 billion times bigger than the sun in volume. So you can guess how big it can be in size. 

biggest star Stephenson
Biggest Star ‘Stephenson 2-18’

One of the biggest stars is UY Scuti (around 800 times bigger than our sun in diameter, but according to some estimations it is 1700 times bigger than our sun).

Many stars in the sky are as big as the UY Scuti, which appears to us very small. But they are so big that it is almost impossible to see them from near.

  • UY Scuti is one of the famous stars, it used to be the biggest known star but the current calculation shows that ‘Stephenson 2-18’ is the largest known star.

Some stars are so big that if we revolve around them in an ordinary airplane, it will take us millions of years to complete one round. So now you must have understood how big are the stars. 

star size comparison

The matter does not just end by coming here. We have known that the stars are big, but now we will know which stars are the biggest and which one is heavier. Because there are many types of stars, so, it is also very important to know them separately.

Brown dwarf stars

These types of stars are about 15–80 times larger and heavier than the Planet Jupiter.

Red dwarf stars

These stars can be 80–800 times heavier and larger than Jupiter Planet. But these stars are smaller compared to our sun. 

Yellow dwarf stars

Our Sun is a “yellow dwarf star’. These types of stars have a size range of 0.8 to 10 times our Sun.

Red giant stars

These stars are much larger than our sun and can have a size range of 20–100 times larger than our sun.

Red supergiant stars

These types of stars are the largest. These stars can be about 100–2000 times larger than the Sun. 

There are some other types of stars like neutron stars, supernovas, and stellar black holes. All these stars fall in the category of red supergiant stars. But they are made at the end of their life cycle, so they can be smaller or bigger.

List of the largest stars:-

Here we have added the list of the 10 largest stars in our universe and their size compared with the diameter of the sun (S≈ 1.4 million km). Because after comparing the size, we can know and feel about “how big are stars”.

Name of the Star Size in Sd  
Stephenson 2-18 2160 Sd
HV 888 (WOH S140) 1975 Sd
V538 Carinae 1870 Sd
WOH G64 1790 Sd
IRAS 05280-6910 (LMC 582) 1740 Sd
Westerlund 1-26 1550 Sd
RSGC1-F02 1530 Sd
RSGC1-F01 1500 Sd
VY Canis Majoris 1420 Sd
AH Scorpii 1410 Sd

How big are the stars compared to Earth?

Our Sun is also a star, it is neither too big nor too small. And now it comes to know, how big is the sun compared to the earth. So, you might be surprised to know that our sun is so big that 1,300,000 earth-size-planet can fit inside the sun.

The Sun is a medium-sized star. Even bigger stars are present in this universe. So just think how big the stars will compare to the earth.

If we compare it with one of the largest known stars UY Scuti (taking 1700 times bigger than the sun), about 6500,000,000,000,000 Earths will fit inside this star.

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