In the early 17th century, craftsmen and scientists introduced a new tool ...
In the early 17th century, craftsmen and scientists introduced a new tool for studying the heavens. The telescope, one of the central instruments of the Scientific Revolution, soon became the astronomer's most essential tool. Now the astronomer could see countless stars and other faint objects never before visible. Suddenly the universe was no longer limited to what the naked eye could see. Read a history of the telescope here.
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