Page 32 - Life beyond the Karman

The purpose of a telescope:
a. To magnify distant objects;
a. To measure radiation from celestial objects; a. To detect radiation from celestial objects.
Ground-based telescopes
Ground-based telescopes give us a window into the universe from Earth. To get the best view, they are located in observatories in areas with low light pollution and usually high altitudes where the atmosphere is thinner.
Some telescopes collect light in the visible part of the spectrum using curved mirrors to focus the light, while others collect radio waves or near-infrared using large dishes that focus the radio waves into a receiver. A larger mirror, or dish, can collect more light and see fainter and more distant objects.
Other wavelengths of the electromagnetic spectrum, like X-rays, gamma rays and UV can’t get through our atmosphere and can only be collected by telescopes in space.
Space telescopes
A space telescope or space observatory is a telescope in outer space used to observe astronomical objects.
They are divided into two types: Satellites which map the entire sky (astronomical survey), and satellites which focus on selected astronomical objects or parts of the sky and beyond. Space telescopes are distinct from Earth imaging satellites, which point toward Earth for satellite imaging and are used for weather analysis, espionage, and other types of information gathering.
Solar telescope
A solar telescope is a special purpose telescope used to observe the sun. They usually detect light with wavelengths in, or not far outside, the visible spectrum.
Radio telescopes
Radio telescopes are directional radio antennae that typically employ a large dish to collect radio waves. These dishes are sometimes constructed of a conductive wire mesh whose openings are smaller than the wavelength being observed. Unlike optical telescopes and infra-red telescopes, radio telescopes can be found anywhere.
Radio telescopes are also used to collect microwave radiation, which has the advantage of being able to pass through the atmosphere and interstellar gas and dust clouds.
Optical telescopes
Optical telescopes gather and focus light mainly from the visible part of the electromagnetic spectrum. They increase the apparent angular size of distant objects as well as their apparent brightness.
Solar telescope
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LIFE BEYOND THE KÁRMÁN LINE - OUTER SPACE