A photo shared on Facebook shows a rock formation that looks like the stump of an oversized tree, with jagged sides resembling tree bark and off-centre tree rings on its flat top.
The photo’s caption reads: “At its height this tree’s trunk was 2.5 miles across; the tree full grown would reach 10 miles into the sky.” That’s right: a tree 4 kilometres wide and 16 kilometres high.
While the photo is real, its caption is not.
Tunisian heritage site
The photo is of Tunisia’s Jugurtha Tableland, a flat-topped mountain close to the north African country’s western border with Algeria. Tunisia has started the process to have Jugurtha declared a Unesco World Heritage Site.
Jugurtha is a rock formation known as a “mesa” – a Spanish word for “table”. As National Geographic explains, mesas are formed by erosion, when water washes “smaller and softer types of rocks away from the top of a hill” to leave a flatter layer of stronger and more durable rock behind.
Cape Town’s Table Mountain is also partly mesa.
Most mesas are usually wider than they are tall. Jugurtha is 0.6 kilometres high, 1.5 kilometres long and 0.5 kilometres wide, which means it isn’t circular, like a tree.
And it’s clearly much smaller than the Facebook post claims.
A tree... how big?
The base of a tree 4 kilometres (2.5 miles) wide would cover an area of central Johannesburg from the magistrate’s court in the west to Jeppestown in the east, and Berea in the north to Doornfontein in the south.
A tree 10 miles high would reach 16 kilometres into the sky.
That’s almost twice the height of Mount Everest, the world’s tallest mountain, which has an elevation of 8.8 kilometres. The highest point on Table Mountain is 1.1 kilometres.
Most commercial aircraft cruise at an altitude of 6.6 miles, or 10.6 kilometres above sea level.
The world’s tallest building is the Burj Khalifa in Dubai, which has 163 above-ground storeys and a height to tip of 829.8 metres, or 0.83 kilometres. That’s just 5.2% of the height of this 16-kilometre-tall tree. It would take about 19 Burj Khalifa buildings, stacked on top of each other, to reach the height of the tree.
Why the story of ancient giant trees?
The claim that Jugurtha is actually the stump of an ancient giant tree is more than just a hoax. It comes out of a branch of the flat-earth conspiracy “theory”, based on an 80-minute YouTube video, that says the planet was covered in forests of towering trees – made of silicone.
The notion is that many of the planet’s large geologic rock formations are in fact the remnants of these massive trees.
Fact-checking site Snopes has already rated the Jugurtha photo as miscaptioned.
“The giant trees of flat-earth theory are impossibly big,” Snopes says. “The tallest tree on earth, Hyperion, only measures 380.3 feet (115.9 metres) tall, about 4,900 feet short of a single mile, and well short of the 10- to 40-mile mark purportedly set by these ancient (and fictional) giant trees.”
Snopes adds: “It’s not clear what gigantic forests might have to do with a flat earth.” – Africa Check (24/01/19)
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