ScienceJune 30, 2026

ionosphere

/aɪˈɒnəˌsfɪər/

Definition

The region of Earth's upper atmosphere that contains a high concentration of ions and free electrons, capable of reflecting radio waves.

Etymology

Derived from the Greek 'ion' (going) and 'sphaira' (globe or ball). It was coined in the early 20th century to describe the atmospheric layer characterized by its ionized state.

In the news

Although not explicitly mentioned in the text body, the term is relevant to the article's focus on remote sensing and space exploration technology, which often relies on communication signals passing through this atmospheric layer.

Northwest Earth and Space Science Pathways Project Celebrates Student Innovation Through ROADS from Earth to Venus National Challenge

Read the full article ↗

NASA Science (.gov)

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