The year is 1609. Up until the previous century, pretty much everyone agreed that the Earth was at the center of the universe. After all, anyone could see that the sun and the moon and the stars all circled around the Earth. If Earth was God's ultimate creation, of course He would want it to be at the center of everything.
There had been a few dissenters along the way, notably Aristarchus in the 3rd century BC, who thought a heliocentric, or sun-centered, universe made more sense. But the Earth-centered notion remained predominate until the 16th century, when Nicolas Copernicus, a lifelong proponent of the heliocentric system, published his life's work, "On the Revolution of the Celestial Spheres."
This book, while flawed in some respects, caught the attention and sparked the imagination of mathematicians and scientists, among them, an Italian teacher named Galileo Galilei. When Galileo heard that someone had discovered a way to use glass lenses to make distant objects appear closer, he decided to make one of the new devices for himself. In 1609, he first pointed his spyglass toward the heavens.
Galileo was astounded by what he saw. Mountains and valleys on the moon. Moons orbiting Jupiter. Venus going through phases like our own moon. "Ears" on Saturn. (His telescope was not sophisticated enough to see the rings, but he could tell it was different from the other disc-shaped planets.) He eventually published his own confirmation of Copernican theories, and he did it in a work targeted not at other scientists, but at the layman.
Such impertinence, telling the common man things that were in opposition to Church teachings, earned Galileo an audience with the Inquisition. He was forced to recant his views, but it was impossible to put the genie back into the bottle. The heliocentric system became the predominate scientific explanation for the movements of celestial objects.
Four hundred years after Galileo first turned a telescope toward the sky, the International Astronomical Union and UNESCO have joined forces to sponsor The International Year of Astronomy 2009. IYA2009, as it is known informally, is a global effort "to help the citizens of the world rediscover their place in the Universe through the day- and night-time sky, and thereby engage a personal sense of wonder and discovery."
One of the goals of IYA2009 is to give ten million people worldwide their first view through a telescope. This means there should be lots of opportunities to look through other people's telescopes, as astronomy clubs, observatories, science centers, and "sidewalk astronomers" share their resources at public events.
Meanwhile, we here at Backyard Astronomy will be checking in throughout the year with science that won't give you a headache, links to cool stuff on the internet, and who knows what else. My husband just handed me instructions for building a replica of Galileo's telescope out of surplus store lenses and PVC pipe, and I said, "Ooh, that looks like fun."
2009 is going to be that kind of year.**********
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