00:00What is the biggest caldera in the world?
00:03It's not Yellowstone.
00:04It's not in Tanzania.
00:06It's in the Philippines.
00:08Meet the Apolaki Caldera, hidden underwater in the Philippine Rise, also known as Benham
00:15Rise, northeast of Luzon.
00:17It is 150 kilometers wide.
00:20That's 93 miles across, more than twice the size of Yellowstone, which is about 60 kilometers
00:27wide.
00:27For comparison, you could fit the entire Metro Manila inside it almost four times.
00:34It was identified as a giant caldera in 2019 by Filipina marine geophysicist Jenny Ann
00:41Barreto and her team.
00:42They named it Apolaki, after the ancient Filipino god of the sun and war, fitting for a giant
00:49this powerful.
00:50So what is a caldera?
00:52It's not just a crater.
00:54A caldera forms when a large amount of magma is removed from beneath a volcano, causing
01:00the ground above to collapse and leaving a massive basin.
01:04Apolaki is ancient and lies deep under the sea, so it is not considered an active volcanic
01:09threat.
01:10But it reveals that one of the largest known calderas on Earth was hiding right under our
01:15nose, and it was a Filipina who found it.
