Space Volcanoes - Shelf Life 360

[AMNH logo unfolds across star-filled space]

[LILTING CLARINET MUSIC PLAYS]

DENTON EBEL (Curator, Division of Physical Sciences): For centuries, people wondered if there were volcanoes on the Moon.

[MECHANICAL CREAKING OF WOODEN GEARS AND CHAINS]

[Archival images and films of people looking through telescopes throughout the ages surround an old illustration of the Moon.]

EBEL: When people looked at the Moon with telescopes, they saw, “Aha! There’s these big round things.”

At the time, it was not understood that impacts make craters that to the untrained eye might look like volcanoes.

[A large meteor travels past the viewer and smashes into the illustrated Moon. A bright flash engulfs the scene.]

GROUND CONTROL VOICE: Apollo 11, this is Houston, over…

[A collage of the Moon’s surface unfolds. Various archival images of astronauts walking and working on the surface are intermixed with illustrations from flight manuals and geological handbooks.]

EBEL: The rocks that the Apollo astronauts brought back unlocked the secrets of the Moon.

[Black and white images of moon rocks appear, labeled, “Apollo 11 Sample.”]

EBEL: Turns out, they’re a lot like the basaltic rocks that we’d find in Iceland, or in Hawaii.  

[Images of brown, pock-marked rocks appear, labeled, “Basalt – Hawaii” and “Basalt – Iceland.”]

EBEL: So, we know that the Moon was volcanically active 4 billion years ago, 3.8 billion years ago.

We think the Moon’s extinct volcanically, in the sense of big eruptions, but we discovered more evidence of volcanoes on our closest planetary neighbor, the planet Mars.

[Mariner spacecraft flies toward Mars, as the planet is slowly rotating in space.]

EBEL: Mars is distinctive in having the largest shield volcano complex in the Solar System, as far as we know.

[Triangle is drawn around an area on Mars’s surface, and labeled “Olympus Mons.” A graphic appears, showing Olympus Mons in profile, as compared to Mount Everest. Everest is labeled as 5.5 miles high, while Olympus Mons is 16 miles high.]

EBEL: Olympus Mons is the highest volcanic edifice on any planet.

[A satellite map of the Earth unfolds around the screen. In an animated diagram, we see a cutaway of the Earth’s surface, down into the mantle. Volcanic islands “grow” over hot spots, and then are pushed off to the side. This process is repeated and a chain of volcanic islands appears.]

EBEL: On the Earth, if you move a tectonic plate over a hot spot in the mantle, you will create volcanic eruptions that go in a line because there’s a track of this hot spot as the plate moves over it.

[The surface of Mars appears, and we see an aerial view of Mons Olympus. The same animated cutaway remains, but now, rather than moving off to the side, the volcanic area over the hotspot remains in place and grows larger and larger.]

EBEL: But If you have no plate tectonics and simply have a crust over a plume, for billions of years, you’re going to build a large volcanic edifice. And that’s what we think we see on Mars.

Mars’s volcanoes have been quiet for a very long time, but it’s a different story elsewhere in the Solar System.

[The Voyager spacecraft flies towards Jupiter, which looms large in the screen.]

EBEL: So, the Voyager mission saw that there was something going on in the moons of Jupiter—

[Voyager flies past Io, one of Jupiter’s moons. Io is a flickering black and white archival image—the same images Voyager sent back in 1979.]

EBEL: —a giant plume of material from an explosive volcano coming off of Io.

[Black and white footage shows a giant plume erupting from Io’s surface into space.]

[A simplified diagram showing Jupiter and four of its orbiting moons, including Io. Io is the closest to Jupiter and as the moons orbit the planet, arrows indicate the pushing and pulling of gravity, as Io is caught in the middle.]

EBEL: Jupiter creates tides in the interior of Io. And these tides actually move the rocks a little bit. Squeeze them. And create heat as a result. And that drives amazing volcanic activity.

[Huge Jupiter dominates the screen. A large smoke-like plume wafts from the much smaller Io (not to scale). A flickering, translucent cloud of energy surrounds both Io and Jupiter.]

[JITTERING ELECTRICAL CURRENT SOUND]

EBEL: The volcanic ejecta—that plume of material—some of it is interacting with the magnetic field of Jupiter and actually forms an electrically-charged cloud or a torus around Jupiter, which has trillions of watts of energy in it.

[CRASH OF THUNDER]

[Jupiter recedes and Io grows in size. Bolts of lightning flash around the moon, along with flickering flames. The faces of gods appear amidst fiery clouds.]

EBEL: The volcanic features on Io have cool names like Pele and Prometheus, which come from mythological beings or locations associated with fire.

But on some worlds, volcanoes breathe ice instead of fire.

[Threads of frost spread out, as if on a pane of glass. They cover the scene, leaving a riven, icy surface.]

EBEL: Saturn’s moon, Enceladus, is home to cryovolcanoes.

[The icy moon Enceladus rotates in the icy background. A line indicating plumes shooting from the bottom of the moon labels them, “Cryovolcanoes.”]

EBEL: It’s not the kind of volcanism that we see on the Earth. Cryovolcanoes are cold volcanoes. But even when things are cold, they can do phase changes if they get heated just a little bit from solid to liquid, or liquid to gas and when that happens you will have eruptive activity.

[Diagram appears of a cutaway into the moon. A strip on top is labeled “Silicate Core.” Below that is a strip of about the same width labeled “Ocean.” Finally, a thick white block at the bottom is labeled “Ice Crust.” Jagged lines are drawn out from the middle ocean layer, burrowing through the ice crust and erupting into columns of steam at the bottom, which are labeled “Vapor Plumes.”]

EBEL: Enceladus has geyser activity where plumes of water, mostly water, are coming from underneath the icy surface erupting into space and freezing.

[Satellite images of Enceladus and Saturn’s rings are collaged together.]

EBEL: What’s really exciting is the amount of energy and activity that go on in these worlds. These are not dead worlds.

[CRYSTALLINE SYNTHESIZER MUSIC]

[Organic forms, like fungus and slime molds, grow out in time lapse across the screen. Diagrams of organic molecules are interspersed throughout.]

EBEL: The geyser activity contains organic material that could contain evidence for microbial life on another body. That would be revolutionary.

[Dissolve into the meteorite collection room at the American Museum of Natural History. A desk sits in the center of the screen, on top are globes of various planets and moons, along with numerous meteorite specimens.]

EBEL: What’s really neat about meteorites is that they give us samples of other worlds.

[Denton Ebel dissolves into the scene, sitting behind the desk. Text identifies him as “Denton Ebel, Division of Physical Sciences.” He holds a small, flat meteorite specimen towards the camera.]

EBEL: This is a piece of rock delivered from a volcano millions of miles away. It fell in Brazil in 1957.

[The screen fills with micrographic images of the meteorite, and an animated CT scan that shows microlayers of the specimen in quick succession. In both, small black holes interrupting the more rocky substance can be seen.]

EBEL: And it is full of these little tiny bubbles of gas. This is what happens in magmas. And this is a volcanic rock delivered to us from Vesta, the asteroid Vesta.

[Back out in space, a computer rendering of Vesta whirls through space towards the viewer. It is cratered and egg-shaped. Other meteors float in the background.]

EBEL: Vesta is special because it’s like a micro-laboratory of planetary formation. Vesta, in miniature, is similar to the Earth in the sense that it has a core and a mantle.

[A cross-section appears over Vesta, indicating a thin crust, a thicker mantle, and a core.]

[CHIMING MUSIC, SOUNDS OF SOMETHING ORGANIC MOVING THROUGH FLUID]

EBEL: By studying samples like this we can start to answer questions about how planets formed, and how life arose.

[Footage of microscopic organisms is collaged with a micrographic image of Vesta, and a backdrop of the stars.]

EBEL: Not just in this solar system, but perhaps elsewhere in the galaxy.

[Credits roll.]