Exomoons
Moons of exoplanets. As of mid-2026 no exomoon has been definitively confirmed, but the 2026 NCCR PlanetS active-moons review (src-active-moons-review-2026-04) argues that Io-like volcanic exomoons could leave outgassing signatures detectable from ground-based telescopes — extending the tidal-heating-driven plume science of io, Europa, enceladus, and triton beyond the solar system.
Detection prospects
- Spectroscopic transit signatures from sodium, potassium, or SO₂ tori around volcanic exomoons.
- Photometric perturbations during transit (TTVs / TDVs).
- Radio emissions from moon-magnetosphere interactions analogous to Io’s footprint on Jupiter.
Astrobiology relevance
Exomoons of giant planets in the habitable zone could host subsurface oceans warmed by tidal-heating, potentially extending the set of habitable environments far beyond rocky planets.