Eerie Features Seen on Mars Are Unlike Anything on Earth : ScienceAlert

Title: Mars’ Unique Spring Spectacle: CO2 Geysers Paint UnEarthly Scenes

In the cold, thin atmosphere of Mars, the dance of seasons presents a charming sight that we Earthlings can only imagine. As winter’s icy grip relaxes, a mesmerizing show of frozen carbon dioxide (CO2) geysers paints the Martian surface in a manner unique to the Red Planet.

When the Martian winter takes hold, about 95% of the planet’s thin atmosphere, which is primarily CO2, freezes and forms a resilient coating on the polar regions. This icy blanket remains undisturbed for months. But as spring arrives and temperatures gently rise, sunlight pierces through the translucent layer, warming the ground below.

The warming ground triggers a remarkable transformation. Frozen CO2 sublimes into vapor, gathering underneath the solid ice, until the pressure becomes too great. The gas eventually escapes through weak points, erupting in geysers that spread darker material across the icy surface.

Captured by the HiRISE camera on NASA’s Mars Reconnaissance Orbiter, these fascinating events unfold on Mars’ polar ice caps. Some geysers can create dark spots as large as 1 km across and erupt at speeds reaching up to 160 km/h. The force behind these CO2 eruptions is remarkable, capable of digging channels and smearing darker dust across the surface.

As appealing as Earth’s beauty may be, Mars offers a spectacle unknown on our home planet. The Martian CO2 geysers form patterns that evoke intrigue and admiration. Scientists have coined these formations ‘spiders’ due to their clustering and the distinct wrinkles they create on the surface.

"We propose that the seasonal ice cap forms an impermeable, translucent slab of CO2 ice that sublimates from the base," said Hugh Keiffer, co-author of the 2006 paper published in Nature, explaining the Keiffer model that describes this process. This phenomenon is unlike any observed on Earth, presenting an awe-inspiring example of Mars’ singular environmental quirks.

As we continue to explore and understand our cosmic neighbor, the Martian CO2 geysers serve as a stunning testament to the universe’s myriad ways of expressing beauty and wonder.