A telescope in orbit above Earth's atmosphere offers almost limitless possibilities. It is an observer's dream. We are restricted with earthbound telescopes. Light pollution, dust particles in the atmosphere, limited observation time all interfere with human observers on Earth.
Light pollution has increased due to the growing size of cities. There is not much an observer can do about light pollution except move the telescope far away from any large urban areas. Dust in the atmosphere is almost exactly like light pollution. It cannot be avoided, but it can be minimized by putting a telescope high above most of the pollution: atop a mountain.
Weather sometimes interferes with observing when we use telescopes on the surface of the Earth. The Hubble Space Telescope is above the atmosphere, so it's never affected by clouds or rain.
If you are an experienced sky-watcher, then you probably have plenty of hints and tips to share with those who want to begin this hobby. If you have any comments or questions about getting the most out of a night of observations, please write us with them. The results will be posted in the Astronomy Gallery.
The Hubble Space Telescope (HST) is a self-contained, remote controlled, space observatory, orbiting the Earth three hundred twenty miles high. This observatory is powered by a solar array that converts sunlight into electricity. It is controlled using radio wavelengths to send commands and to retrieve data, taking pictures in space and transmitting the images to Earth for scientists to study.
If you are interested in the fascinating process by which the Telescope was designed, then you can read about its design and development.
Diagram. A cut-away of the Hubble Space Telescope. Courtesy NASA.
Before HST was put into Earth orbit we expected to see faint objects billions of light years away: stars, quasars, and galaxies. HST should be able to see a hundred times better than any telescope on the Earth's surface. It would have 10 times sharper resolution. HST would be able to detect light from 14 billion light years in the past with a primary mirror that is only 2.4 meters across -- smaller than the largest earthbound telescope.