inner planet


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inner planet

inner planet

n
(Celestial Objects) any of the planets Mercury, Venus, earth, and Mars, whose orbits lie inside the asteroid belt

in′ner plan′et


n.
any of the four planets closest to the sun: Mercury, Venus, Earth, or Mars.
[1950–55]
References in classic literature ?
As these catastrophes occur, the sun will blaze with renewed energy; and it may be that some inner planet had suffered this fate.
When an inner planet is at the greatest apparent distance from the Sun, it is said to be at greatest elongation.
An inner planet, PH3b, may have a rocky composition, like Earth.
The inner planet, Kepler-47b, is three times wider than Earth and whips around the stars every 49 days.
The inner planet, Kepler-47b, orbits the pair of stars in less than 50 days.
Then the inner planet begins passing close to the star, whose gravity makes the orbit rounder and rounder.
Inner planet missions like this one can now be done for about the cost of a private jet or mega-yacht," he said.
The smaller inner planet, Kepler-36b, is rocky and subject to quakes and volcanic eruptions caused by the interplay of the planets' gravitational forces on each other.
INNER PLANET Mercury is not as uninteresting as we first thought
What's more, the two planets have migrated into orbits that have a special gravitational synchrony--every time the outer planet makes one lap around Kepler-9, the inner planet makes two, Holman and his collaborators report online August 26 in Science.
Five of the systems (Kepler-25, Kepler-27, Kepler-30, Kepler-31 and Kepler-33) contain a pair of planets where the inner planet orbits the star twice during each orbit of the outer planet.
In contrast, massive outer planets with elongated orbits act like gravitational slingshots that are likely to eject an inner planet that's on an Earthlike path, notes Hugh R.