When scientists look at the moon, planets, and stars,
they use a telescope. It is one of the most important
scientific instruments. Many people have a telescope
at home. They can watch the night skies whenever
There are two kinds of telescopes. One uses a lens to
gather light and is called a refracting telescope. The other
uses mirrors and is called a reflecting telescope.
The refracting telescope was invented around 500 years
ago. No one is sure who invented it because a number
of people were using lenses made of glass. The famous
Italian astronomer Galileo is one possibility. He may
have been the first person to make a telescope and use
it to look at the moon, planets, and stars. He made
several telescopes, and you can still see them in a
The reflecting telescope was invented a little later.
Scientists knew that curved mirrors changed the way
things were seen. The scientist Isaac Newton may have
been the first person to make a reflecting telescope. He
built it during the sixteen hundreds.
The telescopes that astronomers use today are more
powerful than those used long ago. In fact, the telescope
that you can buy at a local store or online is more
powerful than the ones used by Galileo or Newton.
The most powerful telescopes today are huge and are
kept in special buildings. The buildings are usually on top
of a mountain. This is a good location for a telescope.
There are no city lights around, and the air is a little
cooler and clearer. One of the most famous telescopes is
the Hubble Space Telescope. This is in orbit around Earth
and sends the pictures it takes of the stars back to Earth.