What is the difference between an optical telescope and a radio telescope?
Optical telescopes use polished mirrors or glass lenses to focus visible light as it comes in through the aperture. Radio telescopes are used to study much longer wavelengths than visible light. Often, radio telescopes use a dish to focus the radio waves onto the receiver.
What is a telescope and what is the difference between optical and non optical telescopes?
The two main differences between telescopes is that they are either optical or non-optical. Non-optical telescopes are telescopes that are used by viewers to look at other electromagnetic spectrums other than the visible light. Some of these are radio waves, X-rays, infrared rays, Gamma rays and ultraviolet rays.
What are the advantages of synthetic aperture radar?
SAR systems take advantage of the long-range propagation characteristics of radar signals and the complex information processing capability of modern digital electronics to provide high resolution imagery.
What is the meaning of Synthetic Aperture?
Synthetic aperture is a technique that is used to synthesize a long antenna by combining signals, or echoes, received by the radar as it moves along a flight track. Aperture refers to the opening that is used to collect reflected energy and form an image.
What are the two major types of optical telescope?
There are three primary types of optical telescope: Refractors ( Dioptrics) which use lenses, Reflectors ( Catoptrics) which use mirrors, and Combined Lens-Mirror Systems ( Catadioptrics) which use lenses and mirrors in combination (for example the Maksutov telescope and the Schmidt camera).
What are the advantages of a radio telescope over an optical telescope?
Radio telescopes can be used day or night, they are much less affected by cloudy skies, and they open a new window to observe the Universe. They allow us to observe astronomical objects at a different wavelength than an optical telescope, thus giving an opportunity to compare and contrast the images.
What do optical telescopes do?
An optical telescope is a telescope that gathers and focuses light mainly from the visible part of the electromagnetic spectrum, to create a magnified image for direct visual inspection, to make a photograph, or to collect data through electronic image sensors.
Why it is called Synthetic Aperture Radar?
The well ordered combination of the received signals builds a virtual aperture that is much longer than the physical antenna width. That is the source of the term “synthetic aperture,” giving it the property of an imaging radar.