An example …

The biggest star

The biggest known star in the Universe is VY Canis Major, a red supergiant star that is also classified as a hypergiant because of its very high luminosity. It is located 5,000 light-years away and is 500,000 times brighter and about 30 to 40 times more massive than our Sun. If our Sun was replaced with VY Canis Majoris, its surface could extend to the orbit of Saturn.

More

From TATE:

“It has an average density of 5 to 10 mg/m3”

So how the heck does that work?

How can something with so much mass have such a low density?

How can something with so much mass have such a low density?

by having a very large volume. due to radiation pressure mostly i would assume.

ChrispenEvan said:

How can something with so much mass have such a low density?

by having a very large volume.

I might have asked how they can have such a large volume.

ChrispenEvan said:

due to radiation pressure mostly i would assume.

How can they have such a high radiation pressure?

it is a red supergiant. it is at the end of it’s life as a star and so … see Here for an explanation

ChrispenEvan said:

it is a red supergiant. it is at the end of it’s life as a star and so … see Here for an explanation

Thanks CE.

The Rev Dodgson said:

ChrispenEvan said:

How can something with so much mass have such a low density?

by having a very large volume.

I might have asked how they can have such a large volume.

By having a very low density obviously.

The Rev Dodgson said:

How can something with so much mass have such a low density?

That’s not a mystery. It is just a ball of extremely hot gas, and hot gas does have a very low density.

mollwollfumble said:

The Rev Dodgson said:

How can something with so much mass have such a low density?

That’s not a mystery. It is just a ball of extremely hot gas, and hot gas does have a very low density.

But the Sun has a much higher density, in spite of being a ball of hot gas, with lower mass.