Mount Wilson Observatory summary

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Below is the article summary. For the full article, see Mount Wilson Observatory.

Mount Wilson Observatory, Astronomical observatory located atop Mount Wilson, near Pasadena, California, U.S. Founded in 1904 by George Ellery Hale (1868–1938), it was operated jointly with Palomar Observatory as Hale Observatories (1948–80). Its largest optical telescope, with a diameter of 100 in. (2.5 m), enabled Edwin Hubble and his associates to discover evidence of an expanding universe and to estimate its size.

California Summary

California, constituent state of the United States of America. It was admitted as the 31st state of the union on September 9, 1850, and by the early 1960s it was the most populous U.S. state. No version of the origin of California’s name has been fully accepted, but there is wide support for the

Astronaut outside the International Space Station

space exploration Summary

Space exploration, investigation, by means of crewed and uncrewed spacecraft, of the reaches of the universe beyond Earth’s atmosphere and the use of the information so gained to increase knowledge of the cosmos and benefit humanity. A complete list of all crewed spaceflights, with details on each

United States Summary

United States, country in North America, a federal republic of 50 states. Besides the 48 conterminous states that occupy the middle latitudes of the continent, the United States includes the state of Alaska, at the northwestern extreme of North America, and the island state of Hawaii, in the

astronomical observatory Summary

Astronomical observatory, any structure containing telescopes and auxiliary instruments with which to observe celestial objects. Observatories can be classified on the basis of the part of the electromagnetic spectrum in which they are designed to observe. The largest number of observatories are