[ekianjo]

The sun is roughly a sphere of a fixed size. What is there not to understand ?

[jahnu]

Plenty as it happens. Look up the definition of the surface of a star. It's not as simple or intuitive as one would expect.

[lojack]

I believe he's referring to the "fixed size" part of it, really only an argument a true pedant would make.

[jahnu]

Pedant? Or maybe just making conversation about the interesting differences between human experience and understanding of terms and what definitions astronomers use. Why do so many people on HN react as if every comment is a competition?