A Terrestrial Atmospheric Lens, also known as Terrascope, is a theoretical method of using the Earth's atmosphere as a large lens to build a very powerful telescope, proposed by British astronomer David Kipping. It is based on atmospheric refraction. If built, the terrestrial atmospheric lens would become the largest telescope ever built. Its high resolution would allow to directly image nearby Earth-like planets with a level of detail never seen before. Possible observation targets are Proxima b, located 4.2 light years away, Tau Ceti e, 12 light years away, and Teegarden b, also located 12 light years away. The three planets are currently considered to be potentially habitable. However, using the Sun as a gravitational lens would produce images with higher resolution when imaging potentially habitable exoplanets.
See also Gravitational lens Solar gravitational lens Gravitational microlensing
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