Mother of pearl "noctilucent" clouds on Mars

Noctilucent, mother-of-pearl “dry ice” (carbon dioxide) clouds on Mars (NASA/JPL-Caltech/MSSS).

Field artist Deborah Conn sent me a link to an astonishing set of images recently released by NASA from their Curiosity Rover (if you missed it, I took a group of Field Arts enthusiasts on a virtual field trip to Mars, where we sketched ancient deltas and “Mars blueberries . . .).

The NASA team began documenting “early” clouds from the moment they first appeared in late January:

What resulted are images of wispy puffs filled with ice crystals that scattered light from the setting Sun, some of them shimmering with color. More than just spectacular displays, such images help scientists understand how clouds form on Mars and why these recent ones are different.

In fact, Curiosity’s team has already made one new discovery: The early-arrival clouds are actually at higher altitudes than is typical. Most Martian clouds hover no more than about 37 miles (60 kilometers) in the sky and are composed of water ice. But the clouds Curiosity has imaged are at a higher altitude, where it’s very cold, indicating that they are likely made of frozen carbon dioxide, or dry ice. Scientists look for subtle clues to establish a cloud’s altitude, and it will take more analysis to say for sure which of Curiosity’s recent images show water-ice clouds and which show dry-ice ones. [From https://mars.nasa.gov/news/8956/nasas-curiosity-rover-captures-shining-clouds-on-mars/ ]

This is really great timing, since on June 12 I’ll be teaching a free workshop on Weather, including reading and recording cloud types—I guess I’ll need to add “noctilucent carbon dioxide” clouds! [To sign up and for details, please see https://www.exploringoverland.com/training-trips/2021/5/29/field-arts-skills-workshop-weather

In other news, NASA also released this impressive compilation of 4K video—some of the same places we visited on our virtual field tip.