Why are some Telescopes up out in space?
Why do we need to put some of the Telescopes that use:
a. longer wavelengths either in dry areas on the surface or out in space?
b. shorter wavelengths in space?
The atmosphere distorts images and of course is where weather happens; you can’t use an optical telescope through clouds. Space based telescopes do not have this problem … they essentially have unrestricted views from outside our atmosphere.
The atmosphere distorts images and of course is where weather happens; you can’t use an optical telescope through clouds. Space based telescopes do not have this problem … they essentially have unrestricted views from outside our atmosphere.
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A. Atmospheric gasses such as water vapor absorbs longer wavelengths.
B. Atmospheric temperature gradients distort shorter wavelengths.
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Mostly to get beyond atmospheric distortion; but with some scopes it has to do with the frequency of radiation being sought….like gamma radiation… which is readily absorbed or scattered by the athosphere.
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Ground-based telescopes have to deal with cloudy skies, atmospheric turbulence, half the time its daylight, and even at night there is light pollution in most of the world.
Plus our atmosphere does screen out some wavelengths (such as UV and xrays) and can’t be observed from the ground.
A telescope in space or in Earth orbit can observe 24/7, doesn’t have clouds, dust, turbulent air, or light pollution to deal with.
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Except for the visible band of the spectrum along with some windows in the radio and infrared , the Earth’s atmosphere is opaque to most wavelengths of electromagnetic radiation. This is a good thing for life on Earth, otherwise at best we would have to live in the sea and other bodies of water to avoid death from irradiation from deadly ultraviolet, x-ray and even gamma radiation from space. Our atmosphere protects us from these potent forms of energy that disrupt cellular functions and kill living cells. In order to observe the Universe in the regions of the spectrum however, we have to place telescopes in Earth or Solar orbit. Another reason telescopes are based in space is to eliminate the effects of the turbulence in the atmosphere, which blurs images and reduces the resolution the telescope can achieve. The atmosphere itself also glows, hindering the ability of ground based telescopes to see very faint objects. Basing telescopes in space solves all of these problems, at the cost of no way to service them if something goes wrong in most cases, and a limited lifetime due to the harsh environment of space degrading electronics, batteries and other components of the telescope and the spacecraft that carries it. Moving parts and limited coolant, gas and fuel supplies also mean they have a finite lifetime. Eventually, space telescopes succumb to a failure or running out of coolant, gas or fuel whereas a ground based telescope can be upgraded and operated for decades, critical for studies that require observations over a time period of years or decades.
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