Telescopes: a history
The origin of the telescope is controversial as it is unknown where the telescope was made, when it was made and by who this optical mystery was made by. Although this is the case, the most likely origin of the telescope puts it in the shop of a Dutch spectacle maker named Hans Lippershey in the year 1600AD. It is believed that one day, two children were playing with some of Lippershey’s lenses, they put two of them together and when they looked through the joint lenses at a distant church they found that the church was greatly magnified. They then showed Lippershey this and soon Lippershey started mounting lenses together and sold his invention under the name of his ‘Looker'. In the year of 1608 Lippershey tried to sell his Looker to the Dutch armed forces, but it was turned down after claims that someone else had already invented it.
The news of Lippershey’s invention spread with rapid speed. In that same year, the French ambassador obtained a ‘Looker' for King Henry IV and in the next year these Looker’s were being sold in Paris and Germany under different names, these being "Dutch Trunks," "Perspectives" and "Cylinders." By the end of the year they were also being sold in Milan and Venice and were soon being made in London.
The most influential person connected with the telescope was an Italian scientist named Galileo. Galileo was the first person ever to point the telescope (or as it was then known as the Looker) skyward. The picture was small and fuzzy but he could still make observations. Through his observations Galileo discovered that, unlike previously thought, the moon was not smooth but rather rough and covered with craters. He could also a ribbon of spread-out light which was later to be known as the Milky way galaxy, but his most important discovery through these observations was that Jupiter had four moons which meant that Galileo could prove that the heliocentric views stated fifty years earlier by Copernicus were correct and the geocentric views widely believed were in fact incorrect. (Heliocentric meaning that the universe revolves around the sun and geocentric meaning that the universe revolves around the earth). Galileo published his observations in a 24-page book called The Starry Messenger. In this book he told and showed the world through his observations the things he had discovered.
On the night of April 14, 1611 Federico Cesi held a banquet in Galileo’s honour where Galileo showed the guest his optical instrument. There was an unidentified Greek poet-theologian in the crowd who proposed a name for this instrument. The name that was suggested by this man was the ‘Telescope? which came from ancient Greece. This name was accepted by Galileo and later on that night Federico Cesi, the host, christened Galileo’s instrument with the name the ‘TELESCOPE?
Years after Galileo’s discoveries astronomy boomed as bigger, more accurate and more complex telescopes were made. Because of these telescopes astronomers were now able to make out faint stars and could now calculate stellular distances. But after a while making a telescope bigger no longer improved its view. A large problem now faced astronomers. Because of the atmospheres curvature when looking into space, the view is distorted. For example when looking up into space you may see a twinkling star but the star is not actually twinkling. Actually what looks like twinkling actually is steady starlight that is distorted/bent by the curvature of the earth’s atmosphere. Looking through the atmosphere can be related to what it looked like looking through a glass of water. Telescopes that look through the earth’s atmosphere fall victim to all of these same visual tricks. The astronomers came to the conclusion that the only way to overcome this problem was to have an observatory in space. The astronomer Lyman Spitzer first developed this idea in the 1940s. Through this idea the idea of the Hubble Space Telescope was born. With a telescope in space not looking through the atmosphere all of the previous problems would be overcome. The pictures would be more accurate and sharper.
In the 1970’s the European Space Agency and the National Aeronautics and Space Administration began working together to design and build this outer space telescope, which was later to be known as the Hubble Space Telescope. After the Hubble had been completed April 25 1990, 5 astronauts on the space shuttle Discovery put the Hubble Space Telescope into orbit at around 600 km above the Earth's surface, this is equivalent to 380 miles. A 50-year dream was completed when this happened, as well as when the photographs/images were sent back to earth. More than two decades of dedicated work by scientists, engineers, contractors, and worldwide institutions had gone into the Hubble to make the fifty-year dream a reality.
The next-generation telescopes:
One day the Hubble will have completed its mission, but it will not stop there, the Hubble Space Telescope has a successor, The Next Generation Space Telescope, the NGST, which is being designed right now and may be launched as early as 2008. Scientists and astronomers are hoping that the NGST will teach us more about how the formation of the first stars and galaxies, the evolution of galaxies and the process of star and planet formation. The NGST will be a big improvement on the Hubble due to the fact that the NGST has a larger primary mirror, which will give it ten times the light gathering capability of the Hubble. The NGST will lead us into a whole new era of space exploration.