Encyclopedia of Astrobiology

Living Edition
| Editors: Muriel Gargaud, William M. Irvine, Ricardo Amils, Henderson James Cleaves, Daniele Pinti, José Cernicharo Quintanilla, Michel Viso


  • Tilman Spohn
Living reference work entry
DOI: https://doi.org/10.1007/978-3-642-27833-4_1218-3


The IAU (International Astronomical Union) General Assembly officially defined the term planet in resolution 5A (Resolution_GA26-5-6) in 2006. According to this definition a planet is an object that orbits the Sun, has cleared the neighborhood around its orbit from pre-planetary debris, and has sufficient mass for its self-gravity to maintain a nearly round shape.

See Also


Bioorganic Chemistry Solar System Plate Tectonic Round Shape Planetary Nebula 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Deutsches Zentrum für Luft- und Raumfahrt (DLR)Institut für PlanetenforschungBerlinGermany