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Related to periapsis: true anomaly


n. pl. per·i·ap·si·des (-sĭ-dēz′)
The point at which an orbiting object is closest to the center of mass of the body it is orbiting.
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 closest point to a central body reached by a body in orbit
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.periapsis - (astronomy) the point in an orbit closest to the body being orbited
astronomy, uranology - the branch of physics that studies celestial bodies and the universe as a whole
celestial point - a point in the heavens (on the celestial sphere)
celestial orbit, orbit - the (usually elliptical) path described by one celestial body in its revolution about another; "he plotted the orbit of the moon"
perigee - periapsis in Earth orbit; the point in its orbit where a satellite is nearest to the Earth
perihelion - periapsis in solar orbit; the point in the orbit of a planet or comet where it is nearest to the sun
perijove - periapsis in orbit around Jupiter
perilune, periselene - periapsis in orbit around the moon
apoapsis, point of apoapsis - (astronomy) the point in an orbit farthest from the body being orbited
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
"It's like applying the brakes on a car but instead of brake pads, we used Mars' atmosphere," said Stuart Demcak navigation team lead at NASA's Jet Propulsion Laboratory in Pasadena, California During this time, the spacecraft periapsis altitude (lowest altitude of the orbit) lowered from 151 km (94 miles) to about 132 km (82 miles) above the Martian surface.
The spacecraft is customarily pictured to move along a hyperbolic path as if it was coming from a distant asymptotic state of free space and returning via periapsis back to the asymptotic state.
The other remaining orbital elements, such as the Argument of Periapsis (AoP) and Argument of Latitude (AoL), are set at 0 deg.
With this aim, we know that a bad distribution of the points in the periapsis and the apoapsis leads inexorably to truncation errors of such magnitude that make impossible the task proposed regarding the reduction of errors.
ISRO scientists have planned to set the spacecraft in an orbit of 377 km periapsis (nearest point from the red planet) and 80,000 km apoapsis (farthest point).
The equations of motion are numerically integrated starting at the periapsis in both directions of time, until the particle or spacecraft reaches distances far enough from the Earth and the system Sun-particle can be considered a two-body system.

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