A family enjoying the evening sky with binoculars and a telescope.
Image courtesy Wikimedia Commons

What is a Telescope?

Have you ever looked up and wished that you could take a closer look at the Moon or see the rings of Saturn?  You have probably seen photographs of distant galaxies, exploding stars, and glowing nebulas.  Did you wonder how those photos were taken?

For the past 400 years, telescopes have helped us see into space.  There are many types of telescopes, but they all do pretty much the same thing.  A telescope is an instrument designed to collect light in order to see distant objects.  The word “telescope” comes from the Greek words tele=far and skopein=to look or see.

The first telescope was built by Hans Lippershey in 1608.  Word of this invention spread quickly and by 1609, Galileo Galilei built one and began looking at the sky.  Galileo discovered many things, such as the craters of the Moon, the moons of Jupiter, and the phases of Venus.  He also used his telescopes to study sunspots.

Telescopes have been placed in the middle of deserts, on top of mountains, and even at the South Pole!  The Hubble Space Telescope was placed in outer space and there are even a few neutrino “telescopes” that are built underground.

Last modified May 28, 2008 by Dennis Ward.

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