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  • 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.

You can see them on Jupiter's moon Io.

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如果火山噴發到太空會怎樣? (What If a Volcano Erupted Into Space?)

  • 43 1
    林宜悉 發佈於 2021 年 01 月 14 日
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