From the October 2009 issue

Glenn Chaple’s Observing Basics: Study the Seven Sisters

December 2009: The Pleiades is one of the nearest star clusters to Earth and a popular observing target.
By | Published: October 26, 2009 | Last updated on May 18, 2023
December 2009 Pleiades
The Pleiades star cluster (M45) has caught the attention of sky-gazers since ancient times. Under normal conditions, most observers can see six Pleiads without optical aid.
Chris Schur

Four centuries ago, the Italian astronomer Galileo Galilei opened up the universe with his telescope. Among his discoveries were mountains and craters on the Moon, four bright satellites orbiting Jupiter, and the changing phases of Venus — all of which contradicted the common belief of a perfect Earth-centered universe.