Walking on Lava

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by Coll Metcalfe, Field Producer

There’s a place along the coast of Hawaii’s Big Island where a river of lava flowing down from a steep escarpment dumps into the sea. The scene is otherworldly. For miles there’s nothing but hardened black lava flows, steaming fumaroles, and enormous clouds of steam billowing up from the ocean.

We’re here with Rosaly Lopes of the Jet Propulsions Laboratory and according to the Hawaiian sound tech working with us, we’re to close to the action… way too close. We’re standing on a cracked shelf of hard lava, less than a hundred yards from a river of lava that’s pouring into the sea. Rosaly wanted to take us here because it’s here that she’s made some important insights into volcanoes here on Earth and elsewhere in the solar system.

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 Rosaly Lopes takes a sample of cooled lava on HawaiiMore photos >>


“Volcanism is one of the most fundamental processes in the solar system. That’s how planets lose heat,” she said, as hot lava exploded in the water. “So when you’re looking at the flow here you’re imagining the flows on Venus, on Mars, on Io, and even the cryovolcanic flows on places like Enceladus and Titan. What would they be like?”

Volcanoes are everywhere. We see them here on Earth, on Venus, Mars, even on distant moons like Jupiter’s Io. And what’s interesting is that the processes that drive volcanism in all these places are the same. The only difference is their size.

Of all the worlds in our solar system with volcanoes, Earth’s are some of the smallest. Venus has enormous volcanoes because every 500 million years or so, the planet goes ballistic and literally eats itself. Mars has volcanoes that are many times the size of Earth’s largest mountains. And Io, a moon around Jupiter that’s about a fifth the size of Earth, is the most volcanically active place in the solar system. It has volcanoes with calderas that are hundreds of miles across.

“Standing here, it’s not at all hard to imagine what’s going on out there on a place like Io,” Rosaly said. “I imagine that if we were there right now, we’d see something very similar to this, just a lot, lot bigger.”

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 Cryovolcano on Saturn’s moon, Enceladus. More photos >>

It’s hard to imagine an eruption bigger than what we’re looking at right now. This lava field extends for miles in every direction. In fact, driving in to the location you see that it once inundated a town. There are stop signs and cars buried in hard lava. Kilauea’s been erupting for years, and traveling over the mountain you see all the various calderas and lava floes. This is the most recent flow and you can see gasses rising from cracks in the shiny black surface.

Rosaly and I are actually looking at them. To see how hot it is, I put the heel of my hiking boot near the vent and it starts to melt. The amount of heat actually surprised me until Rosaly told me where I was standing.

“You’re right on top of a lava tube,” she says.

“A lava tube?”

“Yes,” she says. “There’s hot lava right under us.”

“Is that dangerous?”

“Only if the ground is cracked and you’re near the ocean,” she tells me.

“Isn’t that where we are?”


Preview Video: Alien Super Volcanoes

Don’t miss an all-new episode of Known Universe, Cosmic Fury, tonight, Thursday May 13 at 10P et/pt!


  1. Rosaly Lopes |
    January 8, 2016, 10:14 am

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