This is planetary radio. Hi again everyone I'm Matt Kaplan. What a hot show we have for you this week.

Forget about Vesuvius and the Big Island of Hawaii.

There's only one place in the solar system where you'll find over 100 active volcanoes.

And no one knows that lava llathered sphere better than our guest.

Dr. Rosalie Lopez joins us to talk about Jupiter's moon Iyo,

along with a few of Earth's own hotspots, many of which she has visited.

Later Bruce Betts will provide his entertaining review of What's Up.

But let's get started with this volcanic intro from Emily.

That's Planetary Radio for you simply erupting with information. Hi, I'm Emily Lochuwala with questions and answers.

A listener asked, what is the biggest active volcano in the solar system?

Nearly every rocky body in the solar system shows evidence of a volcanic past,

but there are a few planets that we know have active volcanoes. Earth, of course, does have active volcanoes.

At 120 kilometers wide, the biggest active volcano on Earth is Maniloa in Hawaii, which

last erupted in 1984.

The volcano is so massive that it bends the earth's crust downward beneath it,

creating an 8 kilometer deep dent in the earth.

If you measure the volcano's height from the bottom of this

hole, Maniloa's summit lies 17 kilometers or 56,000 feet above its base.

Hawaiian volcanoes are fed by a heat source that lies very deep within the earth, possibly at the boundary between the earth's solid mantle and its molten core.

The earth's heat comes from three sources.

Primordial heat left over from its formation 4.5 billion years ago,

heat from the decay of radioactive elements, and heat released as the molten outer core of the Earth

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