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Galileoscope: Celebrating Telescopes and Space Probes
Color image of ancient telescope.
One of Galileo's first telescopes.

It's the 400th birthday of modern astronomy and we are celebrating with a yearlong sky party called the 2009 International Year of Astronomy.

Color image showing the billions of stars of the milky way galaxy.
The telescope revealed the Milky Way is made up of countless stars.

We begin in the year 1609, at the 'big bang' of modern astronomy when Galileo Galilei learned of a new invention called the "spyglass." Amazed at its ability to make distant objects appear closer, Galileo soon put together his own improved version and created a basic telescope.

When he turned his telescope toward the sky, he opened up a new realm of scientific discovery that leads directly to today's modern space probes and telescopes. In many ways, Galileo is the father of modern day astronomy.

Galileo discovered that the Moon's mountains cast shadows upon its surface, Venus has phases like our Moon, and that the Milky Way "cloud" is made up countless stars. Perhaps Galileo's best-known discovery began on the evening of January 7, 1609 when he first observed three "stars" near the planet Jupiter. A mere eight days later, he had figured out that the starry objects were actually orbiting Jupiter, like a miniature Solar System. It's no wonder that a NASA probe to Jupiter was named after him. In his easy-to-understand book Siderius Nuncius (The Starry Messenger) Galileo published his groundbreaking astronomical discoveries to release his findings to the public.

Fast forward to 2009. In commemoration of Galileo's spirit of ingenuity and discovery, an International Year of Astronomy (IYA) cornerstone project called Galileoscope is putting inexpensive telescopes into the hands of children everywhere, just as Galileo's writings brought a new understanding of our solar system to the average person.

Color image showing Venus cloud patterns.
Venus cloud patterns as seen by the Galileo spacecraft in 1990.

Follow in Galileo's footsteps this month by observing one of the same objects that he did in 1609. After sunset, look for the brightest star-like object in the western sky and you will find the planet Venus. (Venus is the featured planet featured planet in this month's IYA activities).

Nearly 50 years ago, President John F. Kennedy gave his famous Rice University speech, "The eyes of the world are now looking to space, to the Moon and to the planets beyond..." Today NASA's state-of-the-art space telescopes and probes are revealing the secrets of the cosmos. In the past 50 years since the creation of NASA, we have sent probes to all of the planets in our solar system. Even the former planet Pluto will be visited by NASA's New Horizons probe with the closest approach set to take place in 2017.

In addition, this month marks the 5th anniversary of the Mars Exploration Rover landings. Spirit and Opportunity continue to make important discoveries about Mars's watery past.

In March 2009, NASA's Kepler space probe is scheduled to be launched from Kennedy Space Center in Florida. It will be the very first mission capable of finding Earth-sized (and smaller) planets orbiting other stars. The goal for the space telescope's four-year mission is to discover hundreds of Earth-sized planets within three hundred light years of Earth. Using the "transit method," Kepler will constantly monitor more than 100,000 stars similar to our Sun in order to detect "dimming" that occurs when a planet passes in the line of sight.

Could Galileo have imagined sending space probes to the planets and beyond? One thing is certain; Galileo would be amazed to learn how our view of our place in the universe has changed dramatically in the past 400 years since he first pointed his telescope towards the sky.

Artist's illustration of Kepler spacecraft in orbit.
Kepler will hunt Earthlike planets in other solar systems.

Last Updated: 2 February 2011

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Last Updated: 2 Feb 2011