Astrophysics is a sub-discipline of physics that deals with the study of astral or heavenly bodies (such as stars, planets, galaxies, etc.). Astrophysicists typically study interesting questions such as the origin and formation of the universe, galaxies, etc.; existence, origin and properties of black holes, worm holes, etc. A number of these questions may be exploratory in nature or application-based.
Among its various uses, a number of ground-breaking discoveries in physics such as the works of Newton and Galileo were motivated by astrophysics. Nuclear fusion, including the existence of helium and spectral lines of hydrogen; the presence of neutrinos and experimental verification of general relativity, all are part of astrophysics. Astrophysics has led to a number of useful applications in other areas. For example, Computer Tomography or CT was developed from aperture synthesis, a technique developed by an astrophysicist, Martin Ryle, for better resolution. Similarly, small thermal sensors developed for telescopes are nowadays used for temperature control in neonatology units. Several other examples can be found in aerospace, education, energy and other important sectors.
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