400 years of discovery
“I've loved the stars too fondly to be fearful of the night” – Galileo Galilei
This is the year we celebrate the 400th anniversary of the telescope, one of mankind’s greatest achievements and the instrument that helped spur the scientific revolution of the 17th century. Today’s telescopes are immeasurably more complex and far-reaching, but to this day, as in 1609, they continue to alter and expand our knowledge of the universe and its infinite mysteries.
While most astronomers and historians attribute the original invention of the telescope to Hans Lippershey, a German-Dutch lens maker who created the “looker” in 1608, it was Galileo who soon thereafter worked out the principle of the telescope and returned to Venice with an eight-power instrument. Considered a heretic in his time, Galileo used his telescope to support Copernicus’s claim that the Earth was not the centre of the universe.
Over the centuries, the telescope has evolved into a system that reveals and records information that is invisible to the human eye – the gamma-ray, x-ray, infrared and ultraviolet telescopes. The most famous one currently operating is the Hubble Space Telescope, which was launched into space in 1990. Fraught with various problems over the years, Hubble has nevertheless proved invaluable in providing images that have revolutionized astronomy.
Last month alone, Hubble took an image of the stream of celestial bodies crossing the face of Saturn, including Saturn’s giant moon, Titan – an event that takes place every 15 years. The telescope also revealed strong evidence that galaxies are embedded in halos of dark matter.
Europe’s large Herschel and Planck telescopes will soon be launched to investigate the formation of galaxies and the “Big Bang.” The Herschel and Planck spacecraft were built by Thales Alenia Space at the head of a long line of subcontractors across Europe.
Next up will be NASA’s James Webb Space Telescope, a futuristic orbiting observatory with a tennis court-sized, infrared telescope that is anticipated to enter orbit in 2013. James Webb, NASA says, aims “to study every phase in the history of our universe, ranging from the first luminous glows after the Big Bang, to the formation of solar systems capable of supporting life on planets.”
NASA also claims that the telescope will help discover how galaxies evolve, how planetary systems operate and hopefully the very origins of life, much like Galileo modelled his observations 400 years ago.
Clearly the systems have evolved dramatically from the original, but the dream today is the same as it was centuries ago – to advance into space farther than we’ve ever thought possible.
- An afocal optical device made up of lenses or mirrors, usually with a magnification greater than unity, that renders distant objects more distinct, by enlarging their images on the retina.
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