Space Travel
23, May, 2012

Space exploration began with the launch of Sputnik and Astrophysics was born as the application of physics to the phenomena observed by Astronomy, which etymologically means laws of the stars.

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Term Definition
Noise
In a radio receiver, the characteristic hiss produced by the random motion of electrons in the components of the receiver. Cosmic radio waves are also produced by random motions of electrons, so the signal detected by a radio telescope is indistinguishable in nature from the noise generated locally. For this reason, very-low-noise receivers are required for radio astronomy.