heliosphere
noun
he·li·o·sphere
ˈhē-lē-ə-ˌsfir 
-ō-
-ō-
: the region in space influenced by the sun or solar wind
Examples of heliosphere in a Sentence
Recent Examples on the Web
This X-ray glow is radiated when the heavy ions of the solar wind, like carbon and oxygen, grab an electron from neutral atoms in either our outer atmosphere or the heliosphere.
—
Robert Lea,
Space.com,
24 Apr. 2026
To this day, the probes are the only spacecraft in history to operate outside of the heliosphere – the protective bubble of particles and magnetic fields generated by the sun.
—
Eric Lagatta,
USA Today,
21 Apr. 2026
The space agency's Interstellar Mapping and Acceleration Probe, or IMAP, is expected to continue its mission for two years, using scientific instruments to chart the boundaries of the heliosphere and what's going on inside of it.
—
Emily Mae Czachor,
CBS News,
3 Feb. 2026
Everything within the solar wind is inside the Sun’s extended atmosphere, known as the heliosphere, which means that, in a sense, Earth orbits through the Sun itself.
—
Literary Hub,
27 Oct. 2025
See All Example Sentences for heliosphere
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Robert Lea,
Space.com,
24 Apr. 2026
To this day, the probes are the only spacecraft in history to operate outside of the heliosphere – the protective bubble of particles and magnetic fields generated by the sun.
—
Eric Lagatta,
USA Today,
21 Apr. 2026
The space agency's Interstellar Mapping and Acceleration Probe, or IMAP, is expected to continue its mission for two years, using scientific instruments to chart the boundaries of the heliosphere and what's going on inside of it.
—
Emily Mae Czachor,
CBS News,
3 Feb. 2026
Everything within the solar wind is inside the Sun’s extended atmosphere, known as the heliosphere, which means that, in a sense, Earth orbits through the Sun itself.
—
Literary Hub,
27 Oct. 2025
See All Example Sentences for heliosphere
Cite this Entry
“Heliosphere.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heliosphere. Accessed 6 Jul. 2026.
Copy CitationKids Definition
heliosphere
noun
he·li·o·sphere
ˈhē-lē-ə-ˌsfir
-ō-
-ō-
: the region of space that is affected by the sun or solar wind
Love words? Need even more definitions?
Merriam-Webster unabridged
