inferior planet


Also found in: Dictionary, Thesaurus, Wikipedia.
Related to inferior planet: Interior planets

inferior planet

inferior planet, planet whose orbit lies inside that of the earth. There are two inferior planets, Mercury and Venus. They always seem to be close to the sun in the sky; the greatest elongation of Mercury is 28°, and that of Venus, 47°. For this reason, neither can be seen for more than two or three hours after sunset or before sunrise.
The Columbia Electronic Encyclopedia™ Copyright © 2022, Columbia University Press. Licensed from Columbia University Press. All rights reserved.

inferior planet

[in′fir·ē·ər ′plan·ət]
(astronomy)
A planet that circles the sun in an orbit that is smaller than the earth's.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Consider, though, the plight of observers who favor the so-called inferior planets, Mercury and Venus, which circle the Sun inside Earth's orbit and thus never have oppositions.
Of the two inferior planets, Mercury, because of its unusual orbit, requires a special solution to the problem of the equant.
The possibility that the inferior planets might occasionally pass in front of the Sun was not considered until the early part of the seventeenth century, when Kepler predicted transits of both Mercury and Venus for 1631.