ME 350X_Assignment 5 Communication

Communication Essay

The History of the Telescope

Ethan Keyser

ME 350X History of Technology

13 November, 2014

H.R. Statement: Yes, I used the online resources cited in my footnotes, as well as library resources.

There have been many simple inventions over the years that have dramatically changed the world.  Some examples would be the wheel, the button, and penicillin.  All these items are very simple; yet impact the daily lives of people around the world.  Another simple invention that dramatically impacted the world and is still used today would be the telescope.

Although many would think of Galileo as the inventor of the telescope, in actuality, a man named “Hans Lippershey discovered that holding two lenses up some distance apart bring objects closer”.[1]  With this simple observation, Lipperhey built several rough telescopes and applied for a patent.  At the time (1609 AD), Galileo was “in Venice when he heard the rumor that  ‘a Dutchman had constructed a telescope, by the aid of which visible objects, although at a great distance from the eye of the observer, were seen distinctly as if near”.[2]  Galileo began to use his device to study the sky and heavenly bodies.  With his newly christened  “telescope” Galileo was able to make discoveries that would make him very unpopular with the Roman Catholic Church, and the leading scientists at the time.  One example would be that Galileo observed that the planet Jupiter had moons that circled it.

This was in direct conflict with the prevailing theory of the day that everything rotated around the earth.[3]

Two years after Galileo made his telescope, “Johannes Kepler switches from a concave eyepiece to a convex eyepiece. This not only allowed a larger field of view, but it allowed for the projection of images (such as the sun) onto a flat white screen”.[4]  Kepler’s design was an improvement over Galileo’s as far as clarity, but the fact that it inverted images made it less widely used.  After this initial success with the telescope there were many unsuccessful attempts to improve on the design.  In 1673[5], a man named Johannes Hevelius constructed a 140-foot telescope in an attempt to produce clearer images.  However, the great length of the telescope made it very difficult to keep the lenses in line, as the structure would flex.

One important advancement was when “Robert Hooke demonstrates how to shorten the tube by using three or four perfectly flat mirrors to reflect the image back and forth in a shorter tube. A 60-foot long telescope can be reduced to 12 feet long, greatly simplifying support and stability”[6].  This innovation is the basis for many of the modern telescope designs.  Although Hooke made the first reflector telescope, Sir Isaac Newton greatly improved on the design, building a telescope with concave reflecting mirrors made of highly polished metal.  Using a similar design, Sir William Herschel built a telescope with a four-foot diameter mirror.  With this device, Herschel and his sister were able to discover the planet Neptune.

After the Herschel’s telescope, the only major advancement in telescope technology was that they kept getting larger.  Finally in 1937 there was another breakthrough.  “Inspired by sky survey work by Karl Jansky, American engineer Grote Reber takes the telescope into a whole new dimension: the radio telescope. Reber created an instrument that could basically see radio waves – waves that are invisible to our eyes”.[7]  After this advancement scientist began looking for a way to get clearer pictures of space.  Now that telescopes were becoming more clear and powerful, there was another limit to cross—the Earth’s atmosphere.

The solution to this problem was the Hubble space telescope.  “On April 25, 1990, five astronauts aboard the space shuttle Discovery deployed the eagerly anticipated telescope in an orbit roughly 380 miles (600 km) above the Earth’s surface”[8].  Because it is outside of the Earth’s atmosphere, the Hubble is able to see farther into the reaches of space then any previous instrument.  The Hubble has made many discoveries and continues to be of great use almost 25 years after it’s launch.  That said, 25 years is a long time to rely on a piece of equipment, that is why NASA is working on a new electro-magnetic telescope to replace the Hubble.  They will hopefully be launching it into orbit in the near future.

Telescopes represent how a simple invention, (curved lenses) can grow and change the world.  From a homegrown invention, telescopes became multi-million dollar creations.  As their effective range increased, man learned more and more about his surroundings.   As the technology continues to advance, it will be interesting to see what man will be able to learn from the universe in the future.