See it: Origin of mysterious bright green light streaking across Maryland sky identified
The origin of a mysterious throbbing light racing behind clouds across parts of the northeastern U.S. and Canada over the ...
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Venera: The Incredible Probe that the Soviets Sent to Venus
Mars might be our next home, but Venus was our first obsession. In the 20th century, astronomers dreamed of oceans and jungles on Venus - until the Soviet Venera probes proved otherwise. Extreme heat, ...