World's biggest volcano lies beneath Pacific Ocean

Turns out, the world's biggest volcano is a whopping 400 miles wide, and it's underwater.

Researchers just announced the huge Tamu Massif — which lies beneath the Pacific Ocean — can now claim the title of largest in the world. (Via WDAF)

Before now, it was thought Hawaii's Mauna Loa was the biggest volcano in the world, but Tamu Massif completely dwarfs it. (Via U.S. Geological Survey, TAMU Times)

The volcano was hard for scientists to recognize because while it’s 400 miles wide, it’s only 2.5 miles tall. So its slopes are really hard to detect.

Tamu Massif is about 1,000 miles east of Japan, and its summit is about 6,500 feet below the ocean's surface. (Via NOAA)

And while “biggest in the world” is quite the title — we should also note it’s one of the biggest in the universe too.

Olympus Mons on Mars is the largest volcano in Earth's solar system — and Tamu Massif is only about 20 percent smaller. (Via NASA)

But we know what you’re thinking, and, don’t worry — Tamu Massif was formed more than 140 million years ago and has been inactive for a long time.

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