Is there anything bigger than the sun?
For grown-ups: the science
Yes! There are stars out in the universe that are much, much bigger than the sun.
The sun's diameter is about 109 times Earth's, and its volume is about 1.3 million times Earth's. Some stars, called red supergiants, have an even bigger radius than the sun. But comparing star sizes can mean radius, diameter, or mass, so a bigger star isn't always heavier. The sun just looks huge to us because it's the closest star to Earth.
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Transcript
The sun looks like the biggest thing up in the sky, but could there be something out there even bigger?
The sun is so big that 109 Earths could line up across it. But the universe has many stars that are even bigger than the sun.
Big stars are so far away that they look like tiny dots in the sky. The sun looks biggest to us because it's the closest star of all.
Some giant red stars glow hundreds of times wider than the sun. Stars come in all kinds of different sizes.
There are lots of stars in the universe bigger than the sun. The sun just happens to be the star closest to Earth.