Frosty Mars

A Cool Place to Be

Mars is a lot like Earth in some ways. Sure it’s a barren desert planet now, whereas Earth is not. But, like Earth, it has seasonal changes, and if you look at some of its landforms, they look disturbingly familiar. Take this image that the Mars Curiosity rover sent back.

Looks a lot like some places here on Earth, doesn’t it? You can see mountains off in the distance (actually part of the crater that the spacecraft landed in), and lots of sand dunes and rock outcrops nearby. When I see a picture like this, I want to go on a geology field trip — which is what Curiosity is doing for us!

The folks at the European Space Agency have a mission called Mars Express, and it’s doing a bang-up job of sending back high resolution images of Mars from orbit.

The whiter-looking regions here are covered with something most of us are familiar with if we live in climates where winter brings snow and cold weather: frost. In this case, it’s carbon dioxide frost, which forms when the atmosphere gets cold enough to freeze it into particles of ice that coat the ground.

Wondering how cold it is on Mars?  It has a very thin atmosphere, so even though Mars does get sunlight, the temps on the ground are pretty darned cold, usually well below zero (-55 C or -67 F for an average). At its coldest, Mars temps can plunge down to -110 C (-170 F).  I’ve seen suggestions that Mars temperatures can rise above zero on warm summer days; how far they rise depends on the local heating and how much sunlight the ground is getting.

There are more cool images of this cratered region at the link above. They show just how rugged the terrain of Mars is, and remind us that some worlds can look (and sometimes feel) just like home, even if they’re more than 100 million kilometers apart right now!