Apolaki Caldera was discovered in the Philippine Rise, east of Luzon.

Nobody knows for sure what's in our oceans. Earth is around 71 percent water after all, and it's almost scary to think of all the undiscovered creatures and formations in the deep sea (we haven't given up on Atlantis). Scientists have recently found something massive hiding in the Philippine Rise (a.k.a. Benham Rise): Apolaki Caldera, which is possibly the Earth's largest—taking into account all the other ocean secrets we don't know just yet.

The recently discovered caldera is around 150 kilometers wide. To put that into perspective, the distance it takes to drive from Quezon City, Metro Manila to Tarlac City, Tarlac is around 125 kilometers. According to the post of the University of the Philippines Marine Science Institute Geological Oceanography Laboratory, Apolaki's size is comparable to the shield calderas of Mars' Olympus Mons, the largest volcano in our solar system.

Apolaki was named after the god of the sun and war in Philippine mythology, according to the same post. The caldera, which is basically a type of volcano that collapsed on itself, was discovered by a team of scientists: Jenny Anne Barretto—who is a Filipina marine geophysicist based in New Zealand—Ray Wood, and John Milsom. They were working on a paper on the physical features of Benham Rise. We'll keep on the lookout for more awesome scientific discoveries!

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