Add sideways tornadoes to the list of things you can have when your atmosphere is as tenuous as Mars’ is.
“This would be like an F8 tornado sweeping across the surface. These are winds on Mars that will never be seen again unless [there is] another impact.” –Peter Schultz
When we look at ancient impact craters on Mars, one bizarre feature stands out: enormous, outward-going streaks.
These aren’t visible during the day, but appear at night in the infrared, as bright streaks hold onto excessive heat.
To retain heat, the streaks must be made of bare, blocky structures that somehow had all the sand and dust stripped from them.
“That tells us that something came along and scoured those surfaces bare,” says Peter Schultz, lead author on the new study.
What could be that thing that came along? Barreling, sideways tornadoes.
Many craters on worlds contain streaked, scarring pattern headed radially outward from a crater, but the ones on Mars are different.
For the craters’ sizes and the energy that created them, the streaks — only visible in the infrared — extend out much too far.
This isn’t normal ejecta, but an additional phenomenon, which is where the barreling tornadoes idea fits in.
High-velocity impacts can cause high-speed vortices to form and travel just over the surface.
Martian orbiters have already seen normal tornadoes form on the red planet’s surface.
These impacts formed vapor plumes, which travel at supersonic speeds.
Raised surfaces in the way get scoured, creating these unique streaks.
Mostly Mute Monday tells an astronomical story of an object, image, or phenomenon in mostly visuals, with no more than 200 words of text.Ethan Siegel is the author of Beyond the Galaxy and Treknology. You can pre-order his third book, currently in development: the Encyclopaedia Cosmologica.