Glossary
Terms
- albedo
- aphelion
- argument of perihelion
- ascending node
- astrometry
- au (astronomical unit)
- barycenter
- declination
- descending node
- eccentricity
- ecliptic plane
- ephemeris
- geocentric
- geodetic
- GM
- H (absolute magnitude)
- heliocentric
- inclination
- Lagrange points (L1,L2)
- Laplace plane
- LD (lunar distance)
- line of nodes
- longitude of perihelion
- longitude of the ascending node
- mean anomaly
- mean longitude
- mean motion
- meridian
- meteor
- meteoroid
- minor planet
- NEO (near-Earth object)
- nodal points
- nutation
- obliquity
- orbit
- perigee
- perihelion
- period
- phase angle
- right ascension
- semi-major axis
- time of perihelion passage
- topocentric
- true anomaly
- vernal equinox
period
Definition
The time it takes an orbiting body to make one complete revolution around the Sun.
The JPL Solar System Dynamics group’s ephemeris development, maintenance, and improvement tasks are primarily supported by
NASA’s Advanced Multi-Mission Operations System,
which is funded by
NASA’s Science Mission Directorate .