If you could dig a tunnel right through the Earth you could theoretically free-fall to the centre of our planet in just eighteen minutes. You can’t, of course: such a tunnel would have to tolerate temperatures as high as the surface of the Sun and pressures three and a half million times greater than those at the Earth’s surface.
Answer:
Well, to start out, stars are reayling just huge balls of exploding gas. Constant fusion is always taking place benith their surfaces (not that they really have a solid surface). Stars tend to get bigger as they age, and darker two. Younger stars would ussually be smaller and more yellow than an older one. Older ones are bigger and have more of a redish color.
