Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Hi future astronauts. My name is Mrs Carmeli and it's great to be here with you.So today our learning ...

This story is a collaboration with Biography.com. Few things seem as immutable than the Sun—after all, it’s been fusing hydrogen for five billion years, and it’ll keep on ticking for about five ...