Mars north polar cap has a few interesting features for star gazers to see. NASA photo.

Scientists using the Shallow Radar (SHARAD) instrument on NASA's Mars Reconnaissance Orbiter to look beneath Mar's north polar ice cap and get an idea of the lay of the ground think they know how Chasma Boreale and the much discussed series of spiral troughs were formed. The formation of Chasma Boreale and enigmatic spiral troughs have been talked about for four decades by space scientists and amateur astronomers. Mar's north polar region is really just a stack of ice and dust layers up to 2 miles thick and encompassing an area equivalent to Texas. Chasma Boreale is a distinctive land feature as long as the Grand Canyon, only wider and deeper, while the troughs spiral outward from their centers like huge pinwheels.

These spiral troughs have enticed the imagination of viewers for forty years.

What did astronomers and planet scientists using SHARAD to look beneath Mar's north polar cap reveal about the formation of Chasma Boreale and associated spiral troughs? The view beneath Mar's north polar cap suggests strong winds were the main force of geological change involved in the formation of the Chasma Boreale and spiral troughs over millions of years. The geological processes involved would have formed Chasma Boreale and spiral troughs as Mar's north polar ice cap was formed, according to space scientists.