Xem 1-3 trên 3 kết quả Amateur observers
  • in sunlight. This resulted in the development of a wide variety of sophisticated and elegant sundials, which became the standard timekeepers. Sundials were also used as reference for other modes of time-keeping such as hourglasses. Time kept by this method is called apparent solar time. The time between successive appearances of the Sun at the local meridian defines the apparent solar day. Because of Earth’s elliptical orbit, the angular distance it covers per day varies. It moves more rapidly in winter when it approaches perihelion than in summer when it’s near aphelion....

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  • The cordial co-operation of many amateur and professional astronomers in the very successful observations of the Solar Eclipse of January 1, 1889, has again brought forward the desirability of organizing an Astronomical Society of the Pacific, in order that this pleasant and close association may not be lost, either as a scientific or as a social force. You are respectfully invited to become a member of this organization, and to do your part towards making it useful in our community.

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  • In 1665, a book was published that inaugurated the use of the microscope to investigate the natural world. The author was Robert Hooke, a talented artist, architect, and amateur scientist. Hooke wrote Micrographia: Or Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses with Observations and Inquiries Thereupon, at the behest of the newly chartered Royal Society in London, for whom he was working as curator of scientific experiments. In Micrographia, he presented the first detailed observations of everyday objects made with his self-constructed light microscope....

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