Rosse six-foot telescope
Created: 1845
Nickname: The Leviathan of Parsonstown Creator: William Parsons, 3rd Earl of Rosse Location: Birr Castle, County Offaly, Ireland Stats: Lens: 1.8m (diameter) Light Collecting Area: 2.54m squared Light Gathering Power: 129,600x human eye Focal Length: 16m Focal Ratio: f/9 Wavelength: Optical Type: Reflector |
History:
The story of the Leviathan of Parsonstown is one of a man's ambition to build the biggest and best telescope that eventually turned out to be of relatively limited use. William Parsons, the 3rd Earl of Rosse was an avid skygazer who decided that he wanted to construct the world's largest reflecting telescope. In order to do so, he had to construct some of the biggest mirrors in the world, a process which was arduous and slow back in the 19th century. After 17 years of building bigger and bigger mirrors, he finally decided to create the historic 72-inch (1.8m) mirror that made the telescope so famous. Finally complete, the telescope was hung from massive stone walls by chains. The observer was perched some 50 feet in the air gazing down into the telescope's tube. Unfortunately, due to its size and the way it was built, the telescope could only be moved up and down, limiting its view of the sky in terms of east-west direction. The telescope's location was also inconvenient, as the area was notoriously cloudy and windy, creating a lot of atmospheric distortion for observations. Despite this, the telescope remains an important one in history, due to the fact that it was the largest in the world for 75 years and it forced astronomers to consider the importance of where they constructed telescopes. Most of the Leviathan of Parsonstown's observations were of our moon and other planets in our solar system. The most notable contributions of the telescope to the canon of astronomy were the observations of the M51 nebula galaxy. These were the first observations that revealed that galaxies could take on a spiral shape. |