Dust Devil On MARS Shows The Red Planet Looking Lively

Check out that there picture up thurr. Woah. Syntax+grammar vomisplosion. Anyways. That little spectral goody is nothing more than a dust devil wandering about the surface of Mars. A concept, which when thought about, is actually pretty cool.

Bad Astronomy:

Mars is a pretty incredible place. It’s way too easy to easy to think of it as a cold, dry, dead world, but that’s not really true: it has an atmosphere (though thin), it has seasons, and it even has weather.

Circling the Red Planet is the Mars Reconnaissance Orbiter, and with its HiRISE camera it has a fantastic view of the changing face of the planet. And it so happens that sometimes MRO is looking at just the right place, at just the right time, to capture astonishing events… like this magnificent twisting dust devil towering over the landscape:

This picture is just amazing. Dust devils are wind vortices, like tornadoes, but generally not as violent. They form when sunlight warms the surface of Mars. The air just above it gets warmer and rises. If there is a crosswind, it can blow across the rising air and start it spinning like waves breaking on a beach. But since the air is rising, it can lift up vertically while still spinning, forming a dust devil.
I’ve seen them here on Earth all the time; driving across the American southwest one day I saw dozens, including one that was easily a hundred meters across. And so it happens on Mars too. But I’ve never seen one like this! Given the shadow and height of the Sun when this shot was taken, the devil must have been 800 meters high – a half a mile! That’s huge.

The dust devil actually was relatively vertical until a height of about 250 meters above the ground, where the wind caught it and swept it back into that serpentine shape. The path of the dust devil was actually fairly straight; it’s just the plume being whipped around that makes it look wavy (the shadow on the surface adds a wonderful depth to it as well).

First off: I love that people like Phil Plait can make calculations like he does all the time. Makes my lit-centric brain feel positively (and appropriately) useless. Secondly, Mars must be hanging out with Texas. They do things big! A dust devil that’s half a mile high? Awesome.