Subtitles section Play video Print subtitles You can see them on Jupiter's moon Io. You can find some on Neptune's icy moon Triton. Volcanoes erupting so explosively that they reach out into space. Imagine if our own Moon could pull that off. Or even worse. What if a giant volcano on Earth could spew out lava that high? I can tell you this right away — if a volcano erupts with enough power to shoot debris from the Earth's surface into space, we'd all be dead. Most likely. Earth might seem like a volcanic world, but compared to some places in the Solar System, we ain't seen nothing yet. Mars wasn't always the cold red planet we see today. It used to have water and an Earth-like atmosphere. It could even have hosted some simple life-forms. It also had the largest active volcano in the Solar System, Olympus Mons. This giant mountain is three times the height of the biggest mountain we have here on Earth. It hasn't been active for millions of years. But when it was, it could have shot lava beyond the Martian atmosphere. We can't know for sure if it did. Shooting lava into space is a trait that not every planet has. But further in the Solar System, sits the most distant planet from the Sun, Neptune. And it has a moon that's capable of spitting plumes about 8 km (5 mi) into space. This spectacular event was discovered by Voyager 2, the only space probe that's ever visited the distant ice giant's moon. Only Triton isn't erupting with lava. It's spewing out nitrogen ice. And that brings us to another moon in the Solar System. Io is one of Jupiter's moons. It's covered with active volcanoes. Unlike the volcanoes on Earth, Io erupts plumes of sulfur. One of its biggest volcanoes, the active lava lake, Loki Patera, sends such powerful eruptions that we can detect the infrared light from them using the telescopes on Earth. Pretty cool, right? Now, why doesn't our own Moon have similar volcanic shows? Billions of years ago, the Moon was blowing up with violent volcanoes. One hundred million years ago, the Moon was still erupting volcanic burps. If the dinosaurs had invented telescopes, they would have seen some lava spewed from the Moon's surface. Although our Moon doesn't have any active volcanoes today, there's still a lot of magma under its surface. And it could erupt in the future. If humans, or whatever else is dominant on Earth at that time, are interested in astronomy, then they could observe what the dinosaurs missed. The only thing Earth would get from volcanic eruptions on the Moon would be a spectacular view. But it would be a different story if the Earth itself erupted into space. There are two things that affect how volcanoes erupt. The first is gravity. On Mars, the gravity is lower than it is on Earth. That's why it would take longer for magma on the red planet to rise to the surface. On some volcanic worlds, gravity is what's causing eruptions in the first place. Io, for example, has an elliptical orbit. That means that sometimes it gets closer to Jupiter, and the other times it distances itself from the gas giant. Jupiter's enormous gravitational pull constantly deforms Io. And that, in turn, is heating the moon from the inside. This is what's called tidal heating. The second factor is atmosphere. It affects how high volcanoes can eject their plumes. Earth has a thick, turbulent atmosphere. And that's why it can only spew volcanic debris up to 60 km (37 mi) high. Not enough to reach outer space, which generally starts at 100 km (62 mi) above Earth's surface. For Earth to produce an eruption that would spread into space, it would need to be one incredibly huge volcano. Somewhere between 18 and 40 million years ago, the most violent volcanic event happened on Earth. La Garita Caldera, a volcano located in today's Colorado, U.S., ejected 5,000 cubic km (1,200 cubic mi) of volcanic material and killed everything in the radius of at least 160 km (100 mi) around it. And it did, most likely, shoot debris into space. We just weren't around to see that. Volcanic particles can, theoretically, reach space. They just have to move fast enough, developing the minimum speed of 11.2 km/s (7 mi/s). They also need enough energy to withstand Earth's turbulent atmosphere, which will be slowing them down and heating them up at the same time. Lastly, the particles have to be big enough not to evaporate. As I said, it would have to be a huge eruption. Many people would die instantly. They would either be hit by the large chunks of rock or suffocated by the massive gas clouds. Even if you managed to survive that, your days would be numbered because all the energy from such an event would result in global climate change and could end up causing a mass extinction. Our planet could erase humanity from its surface forever, just like it erased dinosaurs some 66 million years ago. And while we will probably never experience volcanoes erupting into space, we could get hit by a huge asteroid one day. But that's a story for another WHAT IF.
B2 moon volcanic earth volcano lava mi What If a Volcano Erupted Into Space? 43 1 林宜悉 posted on 2020/04/04 More Share Save Report Video vocabulary