CLYDE WILLIAM TOMBAUGH - AUTOGRAPH LETTER SIGNED - HFSID 285379
CLYDE TOMBAUGH After writing that he hasn't time to respond in detail an inquiry about how planets are discovered, he proceeds to do just that. Autograph Letter signed: "Clyde W. Tombaugh", 1 page, 7x10. Mesila Park, New Mexico, 1994 February 22. To Michael Petras, Scranton, Pennsylvania.
Sale Price $488.75
After writing that he hasn't time to respond in detail an inquiry about how planets are discovered, he proceeds to do just that.
Autograph Letter signed: "Clyde W. Tombaugh", 1 page, 7x10. Mesila Park, New Mexico, 1994 February 22. To Michael Petras, Scranton, Pennsylvania. In full: "I receive hundreds of letters, and do not have time to answer your questions in detail. Summaries of my work appear in several astronomical journals, and my book, 'Out of the Darkness: Discovery of the Planet Pluto' (1980). See your college library. Also Encyclopedias. From 1929-1943 I made the most extensive planet search in history, over 2/3s of the sky down to the 17½ magnitude - two mags below Pluto. No more planets showed up. The consensus of opinion is: 'There is no Planet X, or 10th planet.' The problem in searching for more faint planets is that one must check nearly 100 million faint star images in scanning alternating view of a pair of plates with an interval of a few days - looking for one that shifts a few millimeters on the plates. Sincerely". Clyde W. Tombaugh (1906-1997) was hired in 1929 as an assistant by the Lowell Observatory in New Mexico to continue the search for a planet beyond Neptune, which had been initiated by Percival Lowell. Tombaugh used a blink microscope to compare photographs of a small part of the night sky and detect the planet. After ten months of painstaking comparisons, on February 18, 1930 he found Pluto in the constellation Gemini. Some of his ashes are carried on the New Horizons spacecraft, which is traveling toward Pluto. A decade after Tombaugh's death, Pluto was demoted to the status of "dwarf planet," in the company of Eris and Ceres. Many astronomers reject this new classification and continue to call Pluto a planet. Lightly toned. Otherwise fine condition.
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