Image of the Day

1 of 11


Credit: NASA/JPL-Caltech/Univ. of Arizona
Friday, Sept. 12, 2014: The tropics of Mars frequently show "Transverse aeolian ridges," or TARs, consisting of small ripples shaped by the wind. These…Read More »

surface features stand up to 20 feet (6 meters) tall, with a few tens of yards (tens of meters) between them. How they form remains a mystery to researchers. These rare banded TARs lie in Iapygia, south of Syrtis Major on Mars. They resemble TARs elsewhere on Mars, except for bands or layers on their northwest faces which do not appear on the southeast sides. Possibly the ripples grew vertically, as material collected at the crests of the ridges.

— Tom Chao   Less «
More from