Changes

The '''telescope''' is an optical instrument made with lenses and mirrors and shows magnified views of distant objects. Its invention is usually credited to Hans Lippershey. However, [[Galileo|Galileo Galilei]] made improvements. He was the first person to use telescope to look at objects in the sky and to write about what he discovered.

The '''telescope''' is an [[optical]] instrument made with lenses and [[mirror]]s and shows magnified views of distant objects. Its [[invention]] is usually credited to [[Hans Lippershey]]. However, [[Galileo|Galileo Galilei]] made improvements. He was the first person to use telescope to look at objects in the [[sky]] and to write about what he discovered.

Galileo discovered the moons that revolve around the planet Jupiter. These can seen by anyone with a pair of modern binoculars; they usually look like three or four stars that are close to Jupiter and all lined up in a straight line. This discovery was important, because at the time philosophers and theologians believed that everything in the universe revolved around the Earth. They even believed that this design reflected the will of God. Galileo's discoveries, and his insistence on publishing them, put him into conflict with the Catholic Church and even led to his being put under house arrest.

Galileo discovered the [[moon]]s that revolve around the [[planet]] [[Jupiter]]. These can seen by anyone with a pair of modern [[binocular]]s; they usually look like three or four [[star]]s that are close to Jupiter and all lined up in a straight line. This discovery was important, because at the time [[philosopher]]s and [[theologian]]s believed that everything in the [[universe]] revolved around the [[Earth]]. They even believed that this design reflected the will of [[God]]. Galileo's discoveries, and his insistence on publishing them, put him into conflict with the [[Catholic Church]] and even led to his being put under house arrest.

The simplest telescopes (and the kind Galileo worked with) are built with two lenses in a tube.

The simplest telescopes (and the kind Galileo worked with) are built with two lenses in a tube.

During the twentieth century, astronomers built huge telescopes. Some of the most famous in the United States are:

During the twentieth century, [[astronomer]]s built huge telescopes. Some of the most famous in the United States are:

*the Lick Observatory on Mount Hamilton near San Jose, California;  

*the [[Lick Observatory]] on Mount Hamilton near San Jose, [[California]];  

*the Yerkes Observatory in the resort area on the shore of Lake Geneva in Wisconsin;  

*the [[Yerkes Observatory]] in the resort area on the shore of [[Lake Geneva]] in [[Wisconsin]];  

*the Mount Palomar Observatory near San Diego;  

*the [[Mount Palomar Observatory]] near San Diego, [[California]];  

*the Keck Telescope on Mauna Kea in Hawai'i.

*the [[Keck Telescope]] on Mauna Kea in [[Hawaii]].

*the Hubble Space Telescope, in Earth orbit.

*the [[Hubble Space Telescope]], in Earth orbit.

[[Category:Astronomy]]

[[Category:Astronomy]]