Researchers have finally explained the Arsia Mons Elongated Cloud (AMEC), a 1,000-mile wispy cloud on Mars first observed in 2018. Published in Nature Geoscience, the study reveals the cloud forms via homogeneous nucleation — water vapor turning directly into ice crystals without dust particles, a process never before directly observed in any planetary atmosphere.
Background
Mars' atmosphere is extremely thin (about 1% of Earth's) and cold, with water ice clouds forming near volcanic regions. The Arsia Mons volcano is one of Mars' largest shield volcanoes, and its elongated cloud pattern had puzzled planetary scientists since 2018.
- Source
- Ars Technica
- Published
- Oct 24, 2026 at 07:50 PM
- Score
- 8.0 / 10