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[kuh-roh-nuh-graf, -grahf] /kəˈroʊ nəˌgræf, -ˌgrɑf/
noun, Astronomy
an instrument for observing and photographing the sun's corona, consisting of a telescope fitted with lenses, filters, and diaphragms that simulate an eclipse.
Also, coronograph.
1885-90; earlier coronograph. See corona, -graph
Related forms
[kuh-roh-nuh-graf-ik] /kəˌroʊ nəˈgræf ɪk/ (Show IPA),
adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for coronagraph
  • They're building a super adaptive optics camera with a coronagraph that blocks a star's light in order to image its planet.
British Dictionary definitions for coronagraph


/kəˈrəʊnəˌɡrɑːf; -ˌɡræf/
an optical instrument used to simulate an eclipse of the sun so that the faint solar corona can be studied
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Encyclopedia Article for coronagraph

telescope that blocks the light of a star inside the instrument so that objects close to the star can be observed. It was invented in 1930 by the French astronomer Bernard Lyot and was used to observe the Sun's corona and prominences.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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