Martian Clouds Might Start with Meteor Trails Through the Atmosphere

Mars, as it was observed shortly before opposition in 2016 by the NASA/ESA Hubble Space Telescope. Credit: NASA/ESA/HST

On Earth, clouds form when enough droplets of water condense out of the air. And those droplets require a tiny speck of dust or sea salt, called a condensation nuclei, to form. In Earth’s atmosphere, those tiny specks of dust are lofted high into the atmosphere where they trigger cloud formation. But on Mars?

Mars has something else going on.

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There’s a Funny Cloud on Mars, Perched Right at the Arsia Mons Volcano. Don’t Get Too Excited, Though, it’s not an Eruption

A funny cloud on Mars. The ESA' Mars Express orbiter captured this image of an elongated cloud forming near the Arsia Mons volcano at the Martian equator. Image: ESA/Mars Express
A funny cloud on Mars. The ESA' Mars Express orbiter captured this image of an elongated cloud forming near the Arsia Mons volcano at the Martian equator. Image: ESA/Mars Express

The ESA’s Mars Express orbiter has spotted a funny cloud on Mars, right near the Arsia Mons Volcano. At first glance it looks like a plume coming out of the volcano. But it’s formation is not related to any internal activity in this long-dead volcano. It’s a cloud of water ice known as an orographic or lee cloud.

The cloud isn’t linked to any volcanic activity, but its formation is associated with the form and altitude of Arsia Mons. Arsia Mons is a dormant volcano, with scientists putting its last eruptive activity at 10 mya. This isn’t the first time this type of cloud has been seen hovering around Arsia Mons.

Continue reading “There’s a Funny Cloud on Mars, Perched Right at the Arsia Mons Volcano. Don’t Get Too Excited, Though, it’s not an Eruption”