periastron(redirected from periastrons)
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Related to periastrons: Apastron
n. pl. per·i·as·tra (-trə)
The point at which an object is closest to the center of mass of the star it is orbiting.
[peri- + Greek astron, star (probably on the model of perihelion); see ster- in Indo-European roots.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
(Astronomy) astronomy the point in the orbit of a body around a star when it is nearest to the star, esp applied to double-star systems
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
The point in the orbit of an object around a star at which the object is at its closest to the star.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited