The black emptiness
Space is—emptiness.
It is black because emptiness has no light of its own. It is neither
cold nor hot because emptiness has no temperature. And, of course, there
is no air or water in space.
But although space itself is emptiness, there are things in it. There
are billions and billions of stars. There are huge clouds of gas and
dust. Comets and chunks of rock called meteoroids rush through parts of
space. Waves of light from stars travel through it. Tiny, invisible
particles move about. Space is the emptiness that surrounds all these
things.
Space and all the things in it make up what we call the universe. We do
not know how big the universe is, but the things farthest away that we
know about are very far away. The light they give off takes thousands
of millions of years to reach us! Perhaps the universe stretches away in
all directions, forever—and never ends!
