Sub-Neptune
Astronomers use the term sub-neptune to refer to large gassy planets, that, while significantly larger than rocky planets, like Planet Earth, are significantly smaller than our Solar system's ice giants, Planet Uranus and Planet Neptune.[1]
While our Solar system does not contain any sub-neptune planets they are commonly found in other stellar systems.[1] Astronomers speculate they will find sub-neptunes that are "rocky gas dwarfs, mini-Neptunes, and water worlds."[2]
References
[edit | edit source]- ↑ 1.0 1.1
"NASA's Webb Lifts Veil on Common but Mysterious Type of Exoplanet". NASA Science. 2025-05-05. Archived from the original on 2026-04-02. Retrieved 2026-07-31.
Though they don’t orbit around our Sun, sub-Neptunes are the most common type of exoplanet, or planet outside our solar system, that have been observed in our galaxy. These small, gassy planets are shrouded in mystery…and often, a lot of haze. Now, by observing exoplanet TOI-421 b, NASA’s James Webb Space Telescope is helping scientists understand sub-Neptunes in a way that was not possible prior to the telescope’s launch.
- ↑ Cite error: Invalid
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