Photographing a beautiful sky is a great passion for many here on Earth, but it can be just as striking on another planet too. Researchers recently presented a stunning new “cloud atlas” of Mars: a database containing 20 years’ worth of images of clouds and storms observed on the red planet.
The cloud atlas is available online, inviting you to browse the many images of martian weather captured by the Mars Express spacecraft. This European Space Agency mission has been in orbit around Mars since 2005, and has taken hundreds of images of the planet using its High Resolution Stereo Camera (HRSC) instrument.
“Clouds on Mars are just as diverse and fascinating as those we see in our skies on Earth, with some features unique to the Red Planet,” said Daniela Tirsch of the German space agency DLR, who presented the work at the Europlanet Science Congress this week.
“One of my favorite phenomena are the beautiful ‘cloud streets’ — linear rows of fleecy clouds that develop around the huge volcanic Tharsis rise and the northern lowlands in northern spring and summer. While they resemble cumulus clouds on Earth, they are formed under different atmospheric conditions. We also see impressive dust clouds that can spread hundreds of kilometers — a phenomena we luckily don’t experience on Earth.”
As well as the cloud streets, the images show phenomena like dust-lifting events, when the combination of high winds and low gravity combine to lift dusty material off the planet’s surface and into the atmosphere. These dust storms can grow very large, even covering the entire planet at times.
Other phenomena captured include Lee waves, which are rippled clouds that are created by steep sided formations like ridges and mountains, and which are also seen on Earth.
Studying the clouds on Mars can help reveal information about its atmosphere, weather, and the dusty material called regolith that covers the planet — all of which is important not only for understanding the planet today and its history but also for future aims like landing heavier spacecraft safely on the planet’s surface.
The researchers have used the cloud atlas to create global cloud maps and to study variation between seasons and locations, and they hope to gather more data to add to it in future, Tirsch said. “As Mars Express has been extended by ESA until at least 2026, this will enable us keep filling this database and refine even further our understand of Mars atmosphere.”
