inner planet


: any of the planets Mercury, Venus, Earth, and Mars whose orbits are within the asteroid belt

Example Sentences

Recent Examples on the Web The inner planet, Kepler-47b, orbits the central stars---a Sun-like one with a smaller companion---every 49.5 days. Sophie Bushwick, Discover Magazine, 29 Aug. 2012 Furthermore, the two planets are orbiting in a resonance, with the inner planet circling its star twice as often as the outer planet. Korey Haynes, Discover Magazine, 3 June 2019 On June 1, the gas giant stood 20° above the inner planet in the western sky, although Venus appeared 10 times brighter. Karri Ferron, Discover Magazine, 11 June 2015 Artist’s rendering of binary system Kepler-47, with outer planet Kepler-47c in the foreground and inner planet Kepler-47b in the bottom right corner can be tough. Sophie Bushwick, Discover Magazine, 29 Aug. 2012 It’s the only inner planet whose surface hasn’t been explored by a robot. Jamie Carter, Forbes, 17 Mar. 2022 The other inner planet, Mercury, is also visible this week just before sunrise. Jamie Carter, Forbes, 31 Oct. 2021 Earth, which is protected by a thick, but livable atmosphere enabled by our own internal energy source—the spinning dynamo of our molten iron core—is the only inner planet with adequate protection from the sun. Caroline Delbert, Popular Mechanics, 16 Oct. 2020 The instability also scattered oddball moons and asteroids and triggered smaller bodies to pummel the inner planets. Paul Voosen, Science | AAAS, 21 Jan. 2020 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'inner planet.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1951, in the meaning defined above

Time Traveler
The first known use of inner planet was in 1951

Dictionary Entries Near inner planet

Cite this Entry

“Inner planet.” Dictionary, Merriam-Webster, Accessed 22 Mar. 2023.

Last Updated: - Updated example sentences
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