he·​li·​o·​sphere | \ ˈhē-lē-ə-ˌsfir How to pronounce heliosphere (audio) , -ō- How to pronounce heliosphere (audio) \

Definition of heliosphere

: the region in space influenced by the sun or solar wind

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Other Words from heliosphere

heliospheric \ ˌhē-​lē-​ə-​ˈsfir-​ik How to pronounce heliospheric (audio) , -​ˈsfer-​ , -​lē-​ō-​ \ adjective

Examples of heliosphere in a Sentence

Recent Examples on the Web

Atmospheric conditions The solar system is enveloped by a huge bubble called the heliosphere. National Geographic, "The solar system, explained," 27 Mar. 2019 Speedy particles that originate outside the solar system, they are partially blocked by the heliosphere. David Grossman, Popular Mechanics, "Voyager 2 Is Getting Close to Interstellar Space," 5 Oct. 2018 The heliosphere is important in keeping dangerous cosmic rays from the interstellar medium out of the main areas of the solar system. John Wenz, Popular Mechanics, "Why Voyager 2 Is In Interstellar Space But Not Out of the Solar System," 13 Dec. 2018 Solar wind is in actuality plasma flowing from the sun, and the heliopause is the last segment of a bubble encompassing the entire solar system known as the heliosphere. David Grossman, Popular Mechanics, "Voyager 2 Enters Interstellar Space," 10 Dec. 2018 The outermost layer of the heliosphere is known as the heliopause. David Grossman, Popular Mechanics, "Voyager 2 Is Getting Close to Interstellar Space," 5 Oct. 2018 For the last 11 years, since 2007, Voyager 2 has been traveling towards the outermost layer of what is known as the heliosphere. David Grossman, Popular Mechanics, "Voyager 2 Is Getting Close to Interstellar Space," 5 Oct. 2018 To Schwadron, the project has three key components: to study the global heliosphere, to discover the origins of particle acceleration, and to continue to take key measurements of space weather phenomena. Elise Takahama, BostonGlobe.com, "NASA selects UNH researchers for mission to study safer space travel," 8 June 2018 To some scientists, those readings meant Voyager 1 had left the heliosphere. Sarah Fecht, Popular Mechanics, "NASA: Yes! Voyager 1 Has Reached Interstellar Space," 12 Sep. 2013

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

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First Known Use of heliosphere

1967, in the meaning defined above

History and Etymology for heliosphere

helio- + -sphere

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Statistics for heliosphere

Last Updated

7 Sep 2019

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Time Traveler for heliosphere

The first known use of heliosphere was in 1967

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More from Merriam-Webster on heliosphere

Rhyming Dictionary: Words that rhyme with heliosphere

Britannica.com: Encyclopedia article about heliosphere

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formidable, illustrious, or eminent

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