Comparison of geostationary Earth orbit with GPS, GLONASS, Galileo and Compass (medium Earth orbit) satellite navigation system orbits with the International Space Station, Hubble Space Telescope and Iridium constellation orbits, and the nominal size of the Earth.[a] The Moon's orbit is around 9 times larger (in radius and length) than geostationary orbit.[b]
The three most important Earth Orbits and the inner and outer Van Allen radiation belt
Various Earth orbits to scale:
  •   the innermost, the red dotted line represents the orbit of the International Space Station (ISS);
  •   cyan represents low Earth orbit,
  •   yellow represents medium Earth orbit,
  •   The green dashed line represents the orbit of Global Positioning System (GPS) satellites, and
  •   the outermost, the black dashed line represents geostationary orbit.

This is a list of types of gravitational orbit classified by various characteristics.

Common abbreviations


List of abbreviations of common Earth orbits

Orbit Name
GEO Geostationary orbit
LEO Low Earth orbit
MEO Medium Earth orbit
SSO Sun-synchronous orbit

List of abbreviations of other orbits

Orbit Name
GSO Geosynchronous orbit
GTO Geostationary transfer orbit
HCO Heliocentric orbit
HEO Highly elliptical orbit
NRHO Near-rectilinear halo orbit
VLEO Very Low Earth Orbit


The following is a list of types of orbits:

Centric classifications

For orbits centered about planets other than Earth and Mars and for the dwarf planet Pluto, the orbit names incorporating Greek terminology is less commonly used

Altitude classifications for geocentric orbits

For Earth orbiting satellites below the height of about 800 km, the atmospheric drag is the major orbit perturbing force out of all non-gravitational forces.[11] Above 800 km, solar radiation pressure causes the largest orbital perturbations.[12] However, the atmospheric drag strongly depends on the density of the upper atmosphere, which is related to the solar activity, therefore the height at which the impact of the atmospheric drag is similar to solar radiation pressure varies depending on the phase of the solar cycle.

Inclination classifications

Directional classifications

Eccentricity classifications

There are two types of orbits: closed (periodic) orbits, and open (escape) orbits. Circular and elliptical orbits are closed. Parabolic and hyperbolic orbits are open. Radial orbits can be either open or closed.

Synchronicity classifications

Geostationary orbit as seen from the north celestial pole. To an observer on the rotating Earth, the red and yellow satellites appear stationary in the sky above Singapore and Africa respectively.

Orbits in galaxies or galaxy models

Pyramid orbit

Special classifications

Pseudo-orbit classifications

A diagram showing the five Lagrangian points in a two-body system with one body far more massive than the other (e.g. the Sun and the Earth). In such a system, L3L5 are situated slightly outside of the secondary's orbit despite their appearance in this small scale diagram.

See also


  1. ^ Orbital periods and speeds are calculated using the relations 4π2R3 = T2GM and V2R = GM, where R = radius of orbit in metres, T = orbital period in seconds, V = orbital speed in m/s, G = gravitational constant ≈ 6.673×10−11 Nm2/kg2, M = mass of Earth ≈ 5.98×1024 kg.
  2. ^ Approximately 8.6 times when the Moon is nearest (363,104 km ÷ 42,164 km) to 9.6 times when the Moon is farthest (405,696 km ÷ 42,164 km).


  1. ^ a b "Types of Orbits". Space Foundation.
  2. ^ "Definition of GALACTOCENTRIC". Retrieved 3 June 2020.
  3. ^ a b Parker, Sybil P. (2002). McGraw-Hill Dictionary of Scientific and Technical Terms Sixth Edition. McGraw-Hill. p. 1772. ISBN 007042313X.
  4. ^ McDowell, Jonathan (24 May 1998). "Jonathan's Space Report". Transatmospheric orbit (TAO): orbital flight with perigee less than 80 km but more than zero. Potentially used by aerobraking missions and transatmospheric vehicles, also in some temporary phases of orbital flight (e.g. STS pre OMS-2, some failures when no apogee restart)
  5. ^ "Stingray VLEO Constellation".
  6. ^ "Attitude control for satellites flying in VLEO using aerodynamic surfaces".
  7. ^ "NASA Safety Standard 1740.14, Guidelines and Assessment Procedures for Limiting Orbital Debris" (PDF). Office of Safety and Mission Assurance. 1 August 1995. p. A-2. Archived from the original (PDF) on 15 February 2013. Low Earth orbit (LEO) – The region of space below the altitude of 2000 km., pages 37–38 (6–1,6–2); figure 6-1.
  8. ^ a b c d "Orbit: Definition". Ancillary Description Writer's Guide, 2013. National Aeronautics and Space Administration (NASA) Global Change Master Directory. Archived from the original on 11 May 2013. Retrieved 29 April 2013.
  9. ^ "Types of orbits".
  10. ^ Vallado, David A. (2007). Fundamentals of Astrodynamics and Applications. Hawthorne, CA: Microcosm Press. p. 31.
  11. ^ Krzysztof, Sośnica (1 March 2015). "Impact of the Atmospheric Drag on Starlette, Stella, Ajisai, and Lares Orbits". Artificial Satellites. 50 (1): 1–18. Bibcode:2015ArtSa..50....1S. doi:10.1515/arsa-2015-0001.
  12. ^ Bury, Grzegorz; Sośnica, Krzysztof; Zajdel, Radosław; Strugarek, Dariusz (28 January 2020). "Toward the 1-cm Galileo orbits: challenges in modeling of perturbing forces". Journal of Geodesy. 94 (2): 16. Bibcode:2020JGeod..94...16B. doi:10.1007/s00190-020-01342-2.
  13. ^ Hadhazy, Adam (22 December 2014). "A New Way to Reach Mars Safely, Anytime and on the Cheap". Scientific American. Retrieved 25 December 2014.
  14. ^ Whipple, P. H . (17 February 1970). "Some Characteristics of Coelliptic Orbits – Case 610" (PDF). Bellcom Inc. Washington: NASA. Archived from the original (PDF) on 21 May 2010. Retrieved 23 May 2012.
  15. ^ a b This answer explains why such inclination keeps apsidial drift small:
  16. ^ "Catalog of Earth Satellite Orbits". NASA. 4 September 2009. Retrieved 4 May 2022.
  17. ^ Merritt and Vasilev, ORBITS AROUND BLACK HOLES IN TRIAXIAL NUCLEI", The Astrophysical Journal 726(2), 61 (2011).
  18. ^ a b Merritt, David (2013). Dynamics and Evolution of Galactic Nuclei. Princeton: Princeton University Press. ISBN 9780691121017.
  19. ^ Leonard David (15 March 2018). "NASA Shapes Science Plan for Deep-Space Outpost Near the Moon".
  20. ^ a b How a New Orbital Moon Station Could Take Us to Mars and Beyond Oct 2017 video with refs
  21. ^ Angelic halo orbit chosen for humankind's first lunar outpost. European Space Agency, Published by PhysOrg. 19 July 2019.
  22. ^ Halo orbit selected for Gateway space station. David Szondy, New Atlas. 18 July 2019.
  23. ^ Foust, Jeff (16 September 2019). "NASA cubesat to test lunar Gateway orbit". SpaceNews. Retrieved 15 June 2020.
  24. ^ "Asteroid Redirect Mission Reference Concept" (PDF). NASA. Retrieved 14 June 2015.
  25. ^ "About Spitzer: Fast Facts". Caltech. 2008. Archived from the original on 2 February 2007. Retrieved 22 April 2007.
  26. ^ "U.S. Government Orbital Debris Mitigation Standard Practices" (PDF). United States Federal Government. Retrieved 28 November 2013.
  27. ^ Luu, Kim; Sabol, Chris (October 1998). "Effects of perturbations on space debris in supersynchronous storage orbits" (PDF). Air Force Research Laboratory Technical Reports (AFRL-VS-PS-TR-1998-1093). Bibcode:1998PhDT.......274L. Archived (PDF) from the original on 3 December 2013. Retrieved 28 November 2013.
  28. ^ Byford, Dorothy (September 2008). "Optimal Location of Relay Satellites for Continuous Communication with Mars".
  29. ^ Keesey, Lori (31 July 2013). "New Explorer Mission Chooses the 'Just-Right' Orbit". NASA. Retrieved 5 April 2018.
  30. ^ Overbye, Dennis (26 March 2018). "Meet Tess, Seeker of Alien Worlds". The New York Times. Retrieved 5 April 2018.