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Astronomy


Astronomy then and now...

In the early 17th century Italian Scientist Galileo, using a very simple telescope, turned it skyward instead of looking at the distant trees and mountains.  What he saw, and what he realized about what he saw, has forever changed the way mankind thinks about the universe. Imagine what it must have been like being the first human to see moons revolve around the planet Jupiter or to see the changing phases of Venus! Because of his observations, Galileo correctly realized Earth’s movement and position around the Sun, and in doing so, gave birth to modern astronomy. Yet Galileo’s telescope was so crude, he could not clearly make out the rings of Saturn.

 

Galileo’s discoveries laid the foundation for understanding the motion and nature of the planets, stars, and galaxies. Building on his foundation, Henrietta Leavitt determined how to measure the distance to stars, Edwin Hubble gave us a glimpse into the possible origin of the universe, Albert Einstein unraveled the crucial relationship of time and light, and 21st-century astronomers are currently discovering planets around stars outside our solar system. Almost daily, using sophisticated successors to Galileo’s telescope, such as the Hubble Space Telescope and the Chandra X-Ray Telescope, more and more mysteries of the universe are being probed and understood. We are living in the golden age of astronomy.
 

 


Unlike other sciences, astronomy welcomes contributions from amateurs. Much of the knowledge we have on subjects such as comets, meteor showers, double and variable stars, the Moon, and our solar system comes from observations made by amateur astronomers. To him, a telescope was not merely a machine made of glass and metal, but something far more—a window of incredible discovery.