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Extras
Glossary
eccentricity
Glossary
Terms
albedo
aphelion
argument of perihelion
ascending node
au (Astronomical Unit)
B-plane
descending node
eccentricity
ecliptic plane
ephemeris
H (absolute magnitude)
inclination
keyhole
LD (Lunar Distance)
line of nodes
longitude of the ascending node
NEO (Near-Earth Object)
nodal points
perigee
perihelion
period
PHA (Potentially Hazardous Asteroid)
semi-major axis
true anomaly
eccentricity
Definition
One half of the major axis of the elliptical orbit; also the mean distance from the Sun.
