deep space

noun

: space well outside the earth's atmosphere and especially that part lying beyond the earth-moon system

Examples of deep space in a Sentence

Recent Examples on the Web
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Power for deep space The Next Gen RTG produces roughly 250 watts of electricity at the start of its operational life. Aamir Khollam, Interesting Engineering, 15 May 2026 Any natural satellites of Psyche could’ve been ejected from the body by ancient impacts—or might’ve even been captured from deep space by chance encounters as the asteroid drifted through the solar system. Meghan Bartels, Scientific American, 14 May 2026 The capability is a necessity if Starship is ever to transport humans into deep space, including to Mars – as Musk has long envisioned. Eric Lagatta, USA Today, 13 May 2026 The upcoming Flight 12 will mark the debut of V3, the first Starship variant that's capable of exploring deep space. Mike Wall, Space.com, 12 May 2026 See All Example Sentences for deep space

Word History

First Known Use

1865, in the meaning defined above

Time Traveler
The first known use of deep space was in 1865

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Cite this Entry

“Deep space.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/deep%20space. Accessed 21 May. 2026.

Kids Definition

deep space

noun
: space outside the earth's atmosphere and especially that part lying beyond the earth-moon system
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