Mars’ 1,000-mile cloud may be driven by physics never seen in nature

Researchers model the Arsia Mons Elongated Cloud, suggesting exotic atmospheric processes at work

By LineZotpaper AI staff

Published24 October 2026

Read Time2 min

A mysterious cloud that appears each Martian spring and summer, stretching over 1,000 miles before vanishing, may be caused by a physical process never before directly observed in any planet’s atmosphere, according to a new study.

Every morning during the Martian spring and summer, a thin, extremely long cloud emerges near the volcano Arsia Mons. Known as the Arsia Mons Elongated Cloud (AMEC), it gradually elongates until it reaches over 1,000 miles, about the distance from New York to Kansas City, before dissipating. The cycle repeats for several months. Since its first detection by a probe in 2018, scientists have been unable to explain the cloud’s existence.

Now, researchers have successfully modeled the cloud’s formation for the first time. Their results suggest it may be driven by exotic physics that has been treated as theoretical and is usually thought not to occur in nature. “We found that we needed to include some exotic physics… physics that, while included in textbooks, is treated as theoretical and usually thought not to happen in nature. It certainly hasn’t been seen in action before,” said Jorge Hernández-Bernal, a planetary scientist at Paris’ Sorbonne Université and lead author of the study, in a press release. “Once we included this physics in our simulations, the AMEC emerged just as we hoped.”

Analysis

Why This Matters

The finding could reveal a fundamental atmospheric process never observed, changing how scientists understand weather on Mars and other planets.
Understanding Martian cloud formation aids future missions by improving predictions of dust and atmospheric conditions.
If confirmed, the exotic physics may also apply to Earth’s atmosphere or exoplanets, opening new avenues in planetary science.

Background

AMEC was first recorded by a Mars probe in 2018. It appears annually during the Martian spring and summer as a wispy formation near Arsia Mons, one of Mars’ giant volcanoes. Until this study, no plausible explanation existed for its origin or persistence. The new research uses computer simulations to replicate the cloud, incorporating physical processes that have been described in textbooks but never directly observed in nature.

Key Perspectives

What to Watch

Whether other research teams can independently replicate the simulation results.
Future Mars orbiters or landers may attempt to observe the cloud more closely to verify the hypothesized physics.
The study’s acceptance in peer-reviewed literature and any follow-up work by the same team.

Sources

A 1,000-mile cloud on Mars may reveal physics never seen in nature · Ars Technica

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11 claims in this story checked against 1 source: 9 supported.

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SupportedThe 1,000-mile Martian cloud may be driven by physics never seen in nature.Ars Technica - All content: “Recently, researchers successfully modeled the cloud’s formation for the first time, their results suggesting that it may be driven by a physical process that has never been directly observed in any planet's atmosphere.”
Partly supportedResearchers modeled the AMEC and suggest exotic atmospheric processes are at work.Ars Technica - All content: “Recently, researchers successfully modeled the cloud’s formation for the first time, their results suggesting that it may be driven by a physical process that has never been directly observed in any planet's atmosphere.”
SupportedThe cloud emerges every morning during Martian spring and summer.Ars Technica - All content: “Every morning during the Martian spring and summer, a thin and extremely long cloud emerges, only to disappear again.”
SupportedThe cloud elongates to over 1,000 miles before dissipating.Ars Technica - All content: “The wispy formation appears near the volcano Arsia Mons and gradually elongates until it reaches over 1,000 miles—about the distance from New York to Kansas City as the crow flies—before dissipating.”
SupportedThe cloud may be caused by a process never directly observed in any planet’s atmosphere.Ars Technica - All content: “Recently, researchers successfully modeled the cloud’s formation for the first time, their results suggesting that it may be driven by a physical process that has never been directly observed in any planet's atmosphere.”
SupportedHernández-Bernal said, “We found that we needed to include some exotic physics… physics that, while included in textbooks, is treated as theoretical and usually thought not to happen in nature. It certainly hasn’t been seen in action before.”Ars Technica - All content: “We found that we needed to include some exotic physics… physics that, while included in textbooks, is treated as theoretical and usually thought not to happen in nature. It certainly hasn’t been seen in action before,”
SupportedHernández-Bernal said, “Once we included this physics in our simulations, the AMEC emerged just as we hoped.”Ars Technica - All content: “Once we included this physics in our simulations, the AMEC emerged just as we hoped.”
SupportedThe quotes are attributed to Jorge Hernández-Bernal, a planetary scientist at Paris’ Sorbonne Université and lead author of the study, speaking in a press release.Ars Technica - All content: “Jorge Hernández-Bernal, a planetary scientist at Paris’ Sorbonne Université and lead author of the study, said in a press release .”
SupportedA probe first recorded the cloud in 2018.Ars Technica - All content: “Since it was first recorded by a probe in 2018, scientists have been unable to find a plausible explanation for the existence of this cloud”
Partly supportedSince the cloud’s first detection, scientists have been unable to explain its existence.Ars Technica - All content: “Since it was first recorded by a probe in 2018, scientists have been unable to find a plausible explanation for the existence of this cloud”
SupportedResearchers modeled the cloud’s formation for the first time.Ars Technica - All content: “Recently, researchers successfully modeled the cloud’s formation for the first time”