# Mars volcano cloud may reveal naturally forming ice without particles

- URL: https://talkfuse.com/story/a-1000-mile-cloud-on-mars-may-reveal-physics-never-seen-in-nature/
- Published: 2026-10-24T11:50:28+00:00
- Updated: 2026-10-24T12:47:17+00:00
- Original publisher: Ars Technica
- Original article: https://arstechnica.com/science/2026/10/a-1000-mile-cloud-on-mars-may-reveal-physics-never-seen-in-nature/
- Topics: Space, Technology

## Key points

- A Martian cloud stretches more than 1,000 miles.
- A new model suggests it forms directly as ice.
- The process may be unlike anything observed in nature.

## Summary

A study has modelled how a long, recurring cloud near Mars’s Arsia Mons volcano may form, offering an explanation for a phenomenon first recorded in 2018. The model suggests the cloud could result from homogeneous nucleation, in which water vapour turns directly into ice without dust or other particles. If confirmed, the process would be the first direct evidence of this kind of ice formation occurring naturally in a planetary atmosphere.

The cloud appears each morning during Martian spring and summer, grows to more than 1,000 miles long, then dissipates; the cycle continues for several months. The model links its formation to winds rising over the 65,000-foot volcano, which rapidly lift moist air and cool it by 30°C within 10 minutes. The proposed process also requires humidity more than 100,000 times higher than any level measured on Earth, and researchers say those conditions had not previously been known to exist on Mars.

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Summarised by TalkFuse (https://talkfuse.com/). Quote the original publisher for the reporting and link this page for the summary and discussion.