NASA Captures Unusual Circular Sand Dunes on Mars, Sparking Interest Among Astronomers Worldwide

On Mars, sand dunes of all forms and sizes are typical. The dunes in the image captured by the high-resolution camera mounted on NASA's Mars Reconnaissance Orbiter (MRO) are almost completely round, which is remarkable and uncommon.

They remain asymmetrical, having steep slip faces on the south ends. But this shows that sand flows typically to the south, although the winds may be unpredictable.

Nearly Circular Sand Dunes on Mars

On November 22, 2022, the University of Arizona's High-Resolution Imaging Experiment (HiRise) camera mounted on NASA's MRO captured the image of sand dunes, which look like slightly uneven splodges. The photo was taken at a latitude of 42.505 degrees and a longitude of 67.076 degrees.

These rare sand dunes were spotted in Mars' northern hemisphere inclined southward, possibly due to the Martian winds moving in that direction. But astronomers were still left baffled as to what caused the dunes to be so nearly spherical.

As per Live Science, the image is part of the series taken by HiRise to monitor how frost melts on the Red Planet at 60 different locations in its northern hemisphere at the end of Mars' winter season. The round dunes look ice-free in the picture, but a previous image reveals that they are covered in frost.

HiRise has been circling and photographing Mars' sand dunes since 2006, assisting scientists in understanding how they migrate and how weather patterns influence them. Sand dunes are spreading from the equator to the poles at a rate of up to 3.3 feet (1 meter) each Martian year, or 687 days on Earth, according to data from the high-resolution camera.

Strange Sights on the Martian Surface

NASA said that researchers also use HiRise to study glacier-like formations and deposits at the base of slopes across the planet where it might be rich in ice even though their source remains a mystery to science until today.

The primary purpose of the MRO was to look for signs of water on Mars. While this mission concluded on December 21, 2010, the spacecraft still functions as a communications bridge back to Earth for future Mars missions and continues to relay startling sights taken by HiRise.

The camera recently identified rocks that resemble a face of a bear. If observed closely, the raised terrain seems to have a bear's snout beneath two circular eyes.

But aside from that, something stranger was also seen last year. NASA's Curiosity rover sent back images to Earth of what may look like a doorway on the Red Planet.

Those images appear to show a clean-cut rectangular hole in a rock, which sparked wild debate among space enthusiasts and on social media, where people offered various theories, including the possibility of extraterrestrial beings.

But NASA said that the structure was only 45 cm high, and geologists pointed out some fracture lines that are visible in the site where the said doorway happens to intersect.

Check out more news and information on Mars in Science Times.