inferior planet

American  

[in-feer-ee-er plan-it] / ɪnˈfɪər i ər ˈplæn ɪt /

noun

Astronomy.

1. (relative to Earth) either of the two planets whose orbits are closer to the sun, namely, Venus and Mercury.

2. (relative to a given planet) any planet whose orbit is closer to the sun.

   From the perspective of Jupiter, Earth is an inferior planet.

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inferior planet British  

noun

1. either of the planets Mercury and Venus, whose orbits lie inside that of the earth

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inferior planet Scientific  

1. Either of the planets Mercury or Venus, whose orbits lie between Earth and the Sun. Because these planets lie in the general direction of the Sun, they can only be seen a few hours before sunrise or after sunset and are always positioned relatively near the horizon, never overhead. Inferior planets go through a complete cycle of phases as viewed from Earth, although their full phase, which occurs on the far side of the Sun, is lost in its glare.

2. Compare superior planet See also inner planet

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Etymology

Origin of inferior planet

First recorded in 1715–20

Example Sentences

When an inferior planet is situated in the same longitude as the sun, and has that luminary between it and the earth, it is said to be in superior conjunction.

From The Sailor's Word-Book An Alphabetical Digest of Nautical Terms, including Some More Especially Military and Scientific, but Useful to Seamen; as well as Archaisms of Early Voyagers, etc. by Belcher, Edward, Sir

At a transit of an inferior planet over the sun, this term means the passing off of the planet from his disc.

From The Sailor's Word-Book An Alphabetical Digest of Nautical Terms, including Some More Especially Military and Scientific, but Useful to Seamen; as well as Archaisms of Early Voyagers, etc. by Belcher, Edward, Sir

An eclipse of the sun, or a transit of an inferior planet, is also much better seen in this way than by any other method of observing the solar disc.

From Half-hours with the Telescope Being a Popular Guide to the Use of the Telescope as a Means of Amusement and Instruction. by Proctor, Richard A. (Richard Anthony)

The extremities of a crescent moon, or inferior planet.

From The Sailor's Word-Book An Alphabetical Digest of Nautical Terms, including Some More Especially Military and Scientific, but Useful to Seamen; as well as Archaisms of Early Voyagers, etc. by Belcher, Edward, Sir

Now this would most certainly be the case were the orbit of an inferior planet in the same plane with the orbit of the earth.

From Astronomy of To-day A Popular Introduction in Non-Technical Language by Dolmage, Cecil Goodrich Julius