You Know it’s Spring on Mars When the Carbon Dioxide is Starting to Sublimate

The northern hemisphere of Mars is beginning to thaw from winter. But for the red planet, that doesn’t mean that birds will sing and flowers will bloom. It means that the carbon dioxide will sublimate. It’s still beautiful though.

Mars in its northern hemisphere is beginning to transition from winter to spring, where it will spend the next 6 months warming up. Observations with the HiRISE (High Resolution Imaging Experiment) onboard the Mars Reconnaissance Orbiter can see the first signs of this transition in the form of dark fans of soil in the northern polar regions.

The north polar ice cap of Mars is seasonal. It grows in the winter and fades in the summer. But it’s not a water ice cap like on the Earth – instead it’s made of frozen carbon dioxide, also known as dry ice. It also doesn’t grow and expand the same way as the ice caps on Earth do, which is by melting from solid to liquid.

Instead, in springtime the northern ice cap sublimates, with the carbon dioxide turning directly from a solid into a gas. This happens at different times from place to place, depending on how much sunlight each patch is getting. In some cases, a layer of ice can sublimate, expanding into a gas and exploding out as a thin jet above the surface. This jet carries with it dust, which spreads out in a fan-like pattern.

As the spring continues, more and more fans will appear until all the ice in the area has sublimated.

Not that summer on Mars is all that fun. At these latitudes you’ll be lucky to find a day above freezing, but at least it beats the winter time lows of -200°.

Paul M. Sutter

Astrophysicist, Author, Host | pmsutter.com

Recent Posts

NASA’s VIPER Rover Will Hunt for Water Near Nobile Crater at Moon’s South Pole

NASA says its VIPER rover will head for the western edge of Nobile Crater near…

8 hours ago

How Could we Light our Cities and Still See the Night Sky?

The night sky is a part of humanity's natural heritage. Gazing up at the heavens…

10 hours ago

Accurately Forecasting the Weather on Mars and Titan

Even meteorologists who forecast the weather on Earth admit that they can’t always accurately predict…

13 hours ago

The Moon was Pummeled Even Harder by Asteroids Than it Looks

The Moon's pitted surface tells a tale of repeated impacts over a long period of…

15 hours ago

Astronomers See Carbon-Rich Nebulae Where Planets are Forming

Understanding the birth of a planet is a challenging puzzle. We know that planets form…

1 day ago

ExoMars Will be Drilling 1.7 Meters to Pull its Samples From Below the Surface of Mars

The ESA just finished testing the drill that will allow the Rosalind Franklin rover to…

2 days ago