Roche limit


ˈrȯsh- How to pronounce Roche limit (audio)
: the distance from a planet's center within which a satellite can neither approach nor reside without being disrupted by tidal forces

Examples of Roche limit in a Sentence

Recent Examples on the Web That places it outside a key location termed the Roche limit. John Timmer, Ars Technica, 8 Feb. 2023 The surprise is that both rings sit well outside the Roche limit, which is at about 1750 km. The Physics Arxiv Blog, Discover Magazine, 21 Apr. 2023 All of these rings also sit within the Roche limit. The Physics Arxiv Blog, Discover Magazine, 21 Apr. 2023 Known as the Roche limit, scientists have long believed any object with a gravitational field can't form a ring beyond a certain distance. Jordan Mendoza, USA TODAY, 10 Feb. 2023 All the rings around Saturn, for example, lie inside of the planet’s Roche limit. Jackie Wattles, CNN, 8 Feb. 2023 And some of it crossed the Roche limit — the area around a planet where a body can no longer hold its shape and is crushed into billions of pieces, forming rings. John Wenz, Discover Magazine, 20 July 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'Roche limit.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


E. A. Roche †1883 French mathematician

First Known Use

1889, in the meaning defined above

Time Traveler
The first known use of Roche limit was in 1889

Dictionary Entries Near Roche limit

Cite this Entry

“Roche limit.” Dictionary, Merriam-Webster, Accessed 24 Jun. 2024.

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