noun
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the branch of astronomy that studies celestial objects by means of the x-rays emitted by them.
noun
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the branch of astronomy concerned with the detection and measurement of X-rays emitted by certain celestial bodies. As X-rays are absorbed by the atmosphere, satellites and rockets are used
"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
x-ray astronomy
Scientific
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The study of celestial objects by measurement of the x-rays they emit. Because the Earth's atmosphere absorbs x-rays, x-ray detectors are usually carried into space on satellites. X-rays are emitted by high-energy objects such as active galactic nuclei, supernova remnants, x-ray binary stars, neutron stars, and the regions around black holes. Objects which do not produce their own x-rays can reflect radiation from nearby stars, making it possible to study the objects using x-ray astronomy; one notable example of this is the analysis of solar x-rays reflected by the Moon.
Etymology
First recorded in 1960–65
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any
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The fourth concept, the Lynx X-ray Observatory, would be the most powerful x-ray astronomy facility ever built, offering intimate views of black holes, active galaxies and violent supernovae across cosmic time.
From
Scientific American
• Aug. 18, 2021
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.