The secret of Earth’s incredible moving star sand dunes
Scientists reveal secrets to Earth’s magnificent desert star dunes, found in Asia, African –– and on Mars
Star dunes, or pyramid dunes, have fascinated historians and captured the imaginations of indigenous people seeking wisdom and meaning. They can be found in Asia, Africa and on Mars and they move around from time to time, rising up to about 1000 feet at their peak. Scientists believe they understand the mechanics of star dunes, by observing a star dune in eastern Morocco called Lala Lallia, meaning ‘highest sacred point’ in local Berber tongue.
The researchers used radar to look inside the dune applying luminescence dating to determine how long Lala Lallia has taken to form, a method that looks at the amount of energy trapped inside the grains of sand. The answer: it started growing about 13,000 years ago, shifted directions and 900 years ago started accumulating roughly 6,400 metric tons of sand annually as wind relentlessly blows sand through the desert.
Read Also: Can you believe the world is running out of sand?
Only about 10% of the world’s sand dunes are star dunes. Driving on sand dunes is a past-time in the Sahara and the Middle East. But Green Prophet’s writer Ajmal bashes dune bashing saying it destroys nature. Trekking by camel or on foot is better, and if you are flexible, watch what you can do on sand dunes below.
“I first encountered star dunes in Namibia 20 years ago, and was instantly amazed at the size of them. I have a vivid memory of the long climb to the top, struggling up very loose sand in the heat of the day,” said geographer Geoff Duller of Aberystwyth University in Wales, co-author of the study published in the journal Scientific Reports.
He told the Deccan Herald:
“I find desert dunes very beautiful,” Duller added. “The sight of the sinuous curves, and the way that the light and shadow changes with the sun mean that they always look different, whether that is in the cool of the morning, the midday sun or near sunset. The different colours of sand in different deserts are also very striking, with yellow, white, red and even black dunes in different parts of the world.”
Earth’s largest star dunes can be found in the the Badain Jaran desert in western China. There are also sand seas in Algeria such as the Grand Erg Oriental and Grand Erg Occidental, and Rub’ al Khali in Saudi Arabia.
Want more on sand? This artist’s work blows back to the sand in Saudi Arabia.
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