Obliquity of the Nine Planets Target Name: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto Spacecraft: Voyager, Viking, Mariner 10, Produced by: Calvin J. Hamilton Copyright: ¨ 1999 Calvin J. Hamilton Date Released: 27 February 1999

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The document "The Solar System" contains additional information related to this image.

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This illustration shows the obliquity of the nine planets. Obliquity is the angle between a planet's equatorial plane and its orbital plane. By International Astronomical Union (IAU) convention, a planet's north pole lies above the ecliptic plane. By this convention, Venus, Uranus, and Pluto have a retrograde orbit, or an orbit that is in the opposite direction from the other planets. The following table lists the obliquity and rotation period of each of the planets.

This image is ¨ copyright 1999 by Calvin J. Hamilton.

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Views of the Solar System Copyright ¨ 1997-1999 by Calvin J. Hamilton. All rights reserved.