Glowering ‘skull’ stares upward from a giant volcanic pit in the Sahara — Earth from space
QUICK FACTS
Where is he? Trou au Natron, Tibesti Massif, Chad [20.96825691, 16.571382232]
What’s in the photo? A skull-shaped structure in a volcanic caldera appears to stare into space
Who took the photo? An anonymous astronaut aboard the International Space Station (ISS)
When was it taken? February 12, 2023
This strange astronaut photo shows a ghostly skull-like structure rising into space from the floor of a giant volcanic pit in the Sahara.
The skull lookalike is located at the bottom of Trou au Natron, also known as Doon Orei – a 3,300-foot-wide (1,000-meter) volcanic caldera or crater in northern Chad. (Trou au Natron translates to “natron hole” in French, while Doon Orei means “big hole” in Teda.)
The volcanic pit was carved out by a massive eruption hundreds of thousands of years ago and lies at the heart of the Tibesti massif, a 480 kilometer-long mountain range that stretches across the center of the country. Sahara Desert via Chad and Libya, according to NASA Earth Observatory.
Seen from space, the caldera floor has an unmistakable skull-shaped appearance. But from the ground (see below), it looks almost unrecognizable.
Related: Check out all the best images of Earth from space
The white color of the mouth, nose and cheeks of the skull is the result of natrona natural blend of sodium carbonate decahydrate, sodium bicarbonate, sodium chloride and sodium sulfate. This salty mixture is extremely flaky and looks like cracked paint up close.
The eye and nose areas are actually cinder cones – steep conical hills built around volcanic vents that dominate the rest of the caldera floor. The darker area to the left of the face is the shadow cast by the high crater rim, which helps give the skull its distinctive shape.
Trou au Natron is now barren and lifeless, but experts believe it was once a thriving glacial lake. In the 1960s, researchers discovered fossils of sea snails and plankton beneath the natron-covered floor of the trench, dating to 14,000 years ago. In 2015, a tracking shipping found algae fossils dating back 120,000 years.
The caldera has been dormant volcanically since shortly after its formation. However, it is located near Tarso Toussidé, a vast volcanic formation covered in a sea of frozen lava (located just beyond the top of the satellite image). Tarso Toussidé is home to a stratovolcano that is believed to still be volcanically active even though it hasn’t erupted in more than 12,000 years, according to data from the Smithsonian Institution. Global Volcanism Program.
Trou au Natron isn’t the only volcanic structure that looks like a skull from space: the Chiltepe Peninsula in Nicaragua’s Lake Managua has a pair of volcanic lakes, each located in its own caldera, which make the landmass look very similar at the caldera in Chad.
