Speaker 1: Welcome to Stuff to Blow Your Mind production of iHeartRadio.
Speaker 2: Hey you welcome to Stuff to Blow Your Mind. My
Speaker 2: name is Robert.
Speaker 3: Lamb and I am Joe McCormick. And today on Stuff
Speaker 3: to Blow Your Mind, we're going to begin a series
Speaker 3: on Jupiter's moon Io. Now, years ago, we did a
Speaker 3: whole series of episodes on the moons of Jupiter as
Speaker 3: a whole, focusing mainly on the four Galilean moons. We'll
Speaker 3: talk more about that in a bit. But recently I
Speaker 3: decided I wanted to come back and do a deeper
Speaker 3: revisit on Io. In particular, iobing Jupiter's innermost moon. And
Speaker 3: this was in part because I learned some new interesting
Speaker 3: things about it. But what really triggered this, this new
Speaker 3: rabbit trail of research, was that one night, I don't know,
Speaker 3: sometime in the past week, I got obsessed with new
Speaker 3: imagery generated by the NASA Juno mission in late twenty
Speaker 3: twenty three and twenty twenty four. And so, Rob, if
Speaker 3: it's all right with you, I'd like to start off
Speaker 3: with us looking at one of these images in particular,
Speaker 3: and folks at home, we will describe it for you.
Speaker 2: All right, let's do it so.
Speaker 3: This is a very crisp color image of Io's northern
Speaker 3: polar region taken by the Juno spacecraft on December thirtieth,
Speaker 3: twenty twenty three, during Juno's fifty seventh close flyby of
Speaker 3: the Moon. The image was released by NASA JPL based
Speaker 3: on data taken by the Juno spacecraft, with some additional
Speaker 3: image processing by somebody named Gerald Eichstadt. And I found
Speaker 3: this picture so weird and thrilling to the imagination. For
Speaker 3: those who can't look it up, if you can look
Speaker 3: it up, i'd recommend checking it out again. Keywords are
Speaker 3: probably Io northern Polar Region, December twenty twenty three. I'm
Speaker 3: sure that I'll pull it up. But for those who
Speaker 3: can't look it up, what we're seeing here is half
Speaker 3: of the Moon as an illuminated hemisphere, fading into darkness
Speaker 3: at the meridian. Now, there's a lot we could say
Speaker 3: about the color of Io, and we'll come back to
Speaker 3: that actually in a few minutes. But in this photo
Speaker 3: we see wide empty planes of a faded rose color,
Speaker 3: a kind of pale, rusty pink, dotted by gaping sunken
Speaker 3: craters and mountains that rise up into space. With alarming sharpness.
Speaker 3: In some cases, they're rising up like thorns, casting these
Speaker 3: long shadows on their night side slopes, And the craters
Speaker 3: are often darker than the plains around them, as if
Speaker 3: containing silent, cold seas of water. That's what I saw
Speaker 3: when I first looked at this. But of course we
Speaker 3: know it's not going to be water in those craters.
Speaker 3: What is in those craters? We'll get to that. Then
Speaker 3: in some spots we see surface features that look almost
Speaker 3: like a biological growth or infection, and a kind of
Speaker 3: mass of yellow orange slime mold shaped just like pure chaos,
Speaker 3: just reaching its fingers out across the moon looking for something.
Speaker 3: And then surrounding these colonies of mold, and around the
Speaker 3: sharp mountains there are pale gray flats that look like
Speaker 3: borders marked in ash. I just love this photo. It
Speaker 3: makes me want to personally explore space. It's bizarre, lovely,
Speaker 3: frightening and seething with drama.
Speaker 2: Yeah, absolutely, this image. It looks like perhaps the pinkish
Speaker 2: disease scalp of a zombie.
Speaker 3: It.
Speaker 2: I also thought, well that this looks exactly like the
Speaker 2: sort of world that would be your destination in a
Speaker 2: Doom video game. Oh, you know, it just looks like
Speaker 2: a hellish planet where you're probably going to have to
Speaker 2: blast demonoids.
Speaker 3: I very much see the zombie comparison, especially like a
Speaker 3: close up on zombie skin, because when you zoom in,
Speaker 3: especially on these mountains, I see something that looks like
Speaker 3: the texture of those liquid latex makeup effects, where there's
Speaker 3: like a scab or a scar on a zombie. That's gonna,
Speaker 3: you know, if it's a full chew movie, it's gonna
Speaker 3: peel off. And sorry to get gross, but that is
Speaker 3: what it looks like.
Speaker 2: It looks infected. It looks infected.
Speaker 3: In more ways than one. But so anyway, this photo
Speaker 3: and some others got my brain racing about IO. I
Speaker 3: started reading some things about it, and I realized that
Speaker 3: there's a lot of interesting stuff about this moon that
Speaker 3: we did not get into in our larger series on
Speaker 3: the Galilean Moons years ago. So I wanted to come
Speaker 3: back and go deep on this moon. That's why we're
Speaker 3: here today.
Speaker 2: Yeah, I was looking back at our notes on the
Speaker 2: Jovian Moons series and I found that, yeah, we didn't
Speaker 2: even really get into the mythology of Io at all,
Speaker 2: Like where this name comes from? And all of that
Speaker 2: is quite fascinating as well, So that's going to be
Speaker 2: fun to explore as we proceed here.
Speaker 3: Yeah, knowing the mythology definitely does enliven and kind of
Speaker 3: throw into shadows over the geology and all of the
Speaker 3: physical facts. So I figure a good place to start
Speaker 3: is to just do a brief kind of refresher course
Speaker 3: on the Moon. So Io is the innermost of the
Speaker 3: what are known as Jupiter's Galilean moons. These are the
Speaker 3: four large moons that were discovered by the Italian astronomer
Speaker 3: and scientific pioneer Galileo Galilei in January sixteen ten using
Speaker 3: a refracting telescope with twenty times magnification power. These four
Speaker 3: moons are from innermost to outermost. So you're starting at
Speaker 3: the planet, going out, you get Io, then you get Europa,
Speaker 3: then Ganymede, than Callisto. Now these are not Jupiter's only moons.
Speaker 3: Jupiter actually has ninety five total moons according to the
Speaker 3: International Astronomical Union, and that's not even everything orbiting the planet.
Speaker 3: That's just the recognized moons. It's not including a bunch
Speaker 3: of small orbiters reaching down to the scale of human furniture.
Speaker 3: We've talked on the show before about how the observation
Speaker 3: of the Galilean moons was not just an important thing
Speaker 3: in the history of astronomy, not just like, oh, we
Speaker 3: learned about some new things out in the sky in
Speaker 3: the Solar System, but it was an important moment in
Speaker 3: the history of science because it was one of many
Speaker 3: pieces of evidence that Galileo marshaled against the geocentric model
Speaker 3: of the cosmos. Because, to simplify the argument, if it
Speaker 3: can be shown that objects orbit another planet like Jupiter,
Speaker 3: why then should we assume that everything in the universe
Speaker 3: orbits the Earth. Maybe instead, the Earth and the planets
Speaker 3: all orbit the Sun, and moons orbit the planets, and
Speaker 3: orbital pathways are a result of some deeper general principle
Speaker 3: other than everything goes around the Earth. Now, technically, when
Speaker 3: Galileo first spied the moons of Jupiter through his telescope,
Speaker 3: at the very beginning, he thought that they were fixed stars.
Speaker 2: He thought he was.
Speaker 3: Looking at stars beyond Jupiter and marked their place. But
Speaker 3: then he looked at Jupiter again later and the stars
Speaker 3: were in a different arrangement, so he realized, like, oh,
Speaker 3: those are not stars, those are something else in the foreground.
Speaker 3: They're going around the planet. And when he first saw them,
Speaker 3: he thought he saw three, not four, because he was
Speaker 3: not able to distinguish Io and Europa. Europa being the
Speaker 3: second innermost of the large moons, he was not able
Speaker 3: to distinguish them as separate points of light. It was
Speaker 3: only in later observations he realized that there were four
Speaker 3: of them. Now, in terms of mass and volume, Io
Speaker 3: is the third largest of Jupiter's moons, after Ganymede and Callisto,
Speaker 3: and it is just slightly larger in diameter than Earth's Moon.
Speaker 3: As the nearest of the Galilean moons to Jupiter, its
Speaker 3: average orbital distance from the planet is four hundred and
Speaker 3: twenty two thousand kilometers or two hundred and sixty two
Speaker 3: thousand miles. Now, the fact that you might know which
Speaker 3: really sets Io apart and is probably going to be
Speaker 3: one of our main focuses in this series, is that
Speaker 3: Io is the most volcanically active object in our solar system,
Speaker 3: with hundreds of active volcanoes at any given time. I
Speaker 3: think there are more than one hundred and fifty active
Speaker 3: volcanoes that have been directly observed, and scientists have estimated
Speaker 3: based on what we have observed, that there are probably
Speaker 3: like four hundred or so in total on the surface. Now,
Speaker 3: just earlier today, I was actually reading the story of
Speaker 3: how the existence of those volcanoes on Io was first confirmed.
Speaker 3: And this actually brings us back to the question of
Speaker 3: the color, the color of the surface of the Moon,
Speaker 3: which I brought up earlier, and where I was reading
Speaker 3: about this was in Carl Sagan's book Cosmos, first published
Speaker 3: in nineteen eighty, sort of as a companion to the
Speaker 3: documentary series he did. Sagan was writing about Io in
Speaker 3: that saying that the following was his favorite of what
Speaker 3: he called the traveler's tales that were returned by the
Speaker 3: voyager probe.
Speaker 2: Are you going to do the voice?
Speaker 3: I appreciate you putting me on the spot, but no,
Speaker 3: I can't do the voice.
Speaker 1: No.
Speaker 2: Anytime I read Sagan, though, I hear it in his voice.
Speaker 3: Oh good, I know exactly what.
Speaker 2: Yeah.
Speaker 3: I hear it in the voice too. Yeah, but I can't. Okay,
Speaker 3: So here it is in my voice, his words, my voice,
Speaker 3: Sagan writes, quote, before voyager we were aware of something
Speaker 3: strange about Io. We could resolve few features on its surface,
Speaker 3: but we knew it was red, extremely read redder than Mars,
Speaker 3: perhaps the reddest object in the Solar System. Over a
Speaker 3: period of years, something seemed to be changing on it
Speaker 3: in infrared light and perhaps in its radar reflection properties.
Speaker 3: We also know that partially surrounding Jupiter in the orbital
Speaker 3: position of Io was a great doughnut shaped tube of
Speaker 3: atoms sulfur and sodium and potassium material somehow lost from Io.
Speaker 3: Oh wow, what a mystery. Okay, so you know, we've
Speaker 3: never gotten close enough to see what's happening on the surface,
Speaker 3: but for some reason, it looks super red, redder than
Speaker 3: anything else we can see around, and it's leaving this
Speaker 3: trail of atoms in space, like it's just spitting out
Speaker 3: atoms into orbit around Jupiter. And then the mystery only
Speaker 3: gets weirder once the voyager probe actually approaches the Moon
Speaker 3: and sends back images in nineteen seventy nine. What they
Speaker 3: see is very strange. First of all, the surface is
Speaker 3: multi colored, as we brought up earlier. If you see
Speaker 3: what they call true color photos of Io, they are
Speaker 3: often overwhelmingly yellow, like a I don't know, a canary
Speaker 3: or a ban and I kind of yellow except I
Speaker 3: don't know, maybe a little paler and more sickly, some
Speaker 3: kind of vomitous duckling yellow with these blotches of red, pink, gray,
Speaker 3: and green. I feel like this has too normative of
Speaker 3: a connotation, but it really does always kind of remind
Speaker 3: me of sickness in some way, not trying to say
Speaker 3: io is a bad place. So one of the happier
Speaker 3: comparisons that astronomers sometimes make about the different coloration patterns
Speaker 3: is they call it a pizza planet. They're like, it's
Speaker 3: got like cheese and pepperonis and olives and all that.
Speaker 2: Well that's a way to make it attractive, I guess.
Speaker 2: But yeah, it does look like some sort of a
Speaker 2: strange like nergal world.
Speaker 3: So yeah, yeah. Also, scientists looking at the images of
Speaker 3: iosurface realized it was missing something impact craters due to
Speaker 3: its position near the asteroid belt. Sagan writes that this
Speaker 3: object really would have to have undergone repeated impacts from space,
Speaker 3: should be hammered by asteroids, by things coming down on
Speaker 3: it and leaving pocks in its surface that we would
Speaker 3: be able to see, you know, just like look at
Speaker 3: the Moon. It should maybe look something like that, but
Speaker 3: instead its surface showed little to no sign of impacts,
Speaker 3: as if something was rapidly erasing the evidence of collisions. Now,
Speaker 3: whatever was doing that erasing could not be atmospheric in nature,
Speaker 3: because Io has almost no atmosphere. It does have an atmosphere,
Speaker 3: but it's incredibly thin, made primarily of sulfur dioxide. If
Speaker 3: those surface features are being erased, they couldn't be erased
Speaker 3: by erosion of running water because the conditions on the
Speaker 3: surface of Io would not permit liquid water. So it
Speaker 3: had been theorized by some astrophysicists. Segan names an astrophysicist
Speaker 3: named Stanton Peel that Io might have erupting volcanoes due
Speaker 3: to tidal heating of its interior. So this is a
Speaker 3: frictional heating of the inside of the planet caused by
Speaker 3: gravitational forces. We'll explain more about this as we go
Speaker 3: on in the series. But that could lead to volcanic eruptions,
Speaker 3: which could do the job of repaving the surface if
Speaker 3: these volcanoes existed. But up until this point in nineteen
Speaker 3: seventy nine, there was no way to know if any
Speaker 3: of that was true. It was just an idea. That's
Speaker 3: one thing that could be going on. Here then Sagan
Speaker 3: tells of the discovery. He writes, quote Linda Moribto, a
Speaker 3: member of the Voyager navigation team responsible for keeping Voyager
Speaker 3: precisely on its trajectory, was routinely ordering a computer to
Speaker 3: enhance an image of the edge of Io to bring
Speaker 3: out the stars behind it. To her astonishment, she saw
Speaker 3: a bright plume standing off in the darkness from the
Speaker 3: satellite's surface, and soon determined that the plume was in
Speaker 3: exactly the position of one of the suspected volcanoes. Voyager
Speaker 3: had discovered, the first active volcano being on the Earth.
Speaker 3: We now know of nine large volcanoes spewing out gas
Speaker 3: and debris. Remember this was in nineteen eighty when this
Speaker 3: book was written. Nine large volcanoes spewing out gas and debris,
Speaker 3: and hundreds, perhaps thousands of extinct volcanoes on Io. The
Speaker 3: debris rolling and flowing down the sides of the volcanic mountains,
Speaker 3: arching in great jets over the polychrome landscape is more
Speaker 3: than enough to cover the impact craters. We are looking
Speaker 3: at a fresh planetary landscape, a surface newly hatched. How
Speaker 3: Galileo and Huygens would have marveled now I love that
Speaker 3: story for multiple reasons, one of which is the idea
Speaker 3: that the plume from the volcano was spotted not by
Speaker 3: somebody who was intentionally hunting four volcanoes, but in the
Speaker 3: process of trying to better resolve navigation navigationally relevant data.
Speaker 3: But I also love how it paints this picture of
Speaker 3: Io as a place of a freshness of chain.
Speaker 2: Rob.
Speaker 3: I think we've talked about this on the show before
Speaker 3: that often when we think of anything beyond Earth, things
Speaker 3: in space, we tend to think of a kind of inert, changeless,
Speaker 3: frozen or dead landscape, places where nothing all that interesting
Speaker 3: ever really happens. Like what is interesting about the places
Speaker 3: beyond Earth is kind of a I don't know, features
Speaker 3: of permanent interest, just the way things are and have
Speaker 3: always been and will always be. Obviously, we know that's
Speaker 3: not true, and if you like fast forward the tape
Speaker 3: of geologic time and cosmic time, things change a lot.
Speaker 3: But just thinking about other planets and moons seems like
Speaker 3: not a lot is happening there, and that is absolutely
Speaker 3: not the case on the surface of Io. You know
Speaker 3: he's talking Segan here is talking about Io as a
Speaker 3: place where the surface changes on a timescale of months.
Speaker 2: It is a dynamic world.
Speaker 3: And so this leads to another thing he gets into
Speaker 3: about the chemistry of Io and its volcanic activity, and
Speaker 3: how this actually relates to the strange patterns of what
Speaker 3: he called the polychrome surface, the different coloration patterns we
Speaker 3: see on the surface. Sagan writes that this is actually
Speaker 3: what we would expect to see from the release of
Speaker 3: molten sulfur and the interactions of sulfur compounds from Io's
Speaker 3: volcanoes and on the surface of the moon. So you
Speaker 3: get like these black coloration at the hottest places where
Speaker 3: the sulfur is just coming out, and maybe near the
Speaker 3: top of the volcano or the mouth of the volcano,
Speaker 3: and then nearby where there would be flows of what's
Speaker 3: coming out of the volcanoes, you get something more like
Speaker 3: red and orange. And then beyond that you get these
Speaker 3: big empty planes that are just kind of like yellow,
Speaker 3: yellowish sulfur. Now, on the subject of what is coming
Speaker 3: out of the mouth of the volcanoes, or what might
Speaker 3: be forming sort of lakes or rivers of flows beyond
Speaker 3: beyond a volcano on Io, it's worth noting that materials
Speaker 3: ejected from volcanoes tend to be very hot. That's true,
Speaker 3: whether we're talking about Earth or Io. They can form
Speaker 3: these searing lava flows. But a crazy fact that I
Speaker 3: came across is that apparently lava flows on Io are
Speaker 3: even hotter than lava flows on Earth. You know, I
Speaker 3: might have just assumed that la lava is going to
Speaker 3: be roughly the same temperature wherever it is. You know,
Speaker 3: once it sort of reaches the surface, it's you know,
Speaker 3: it's probably cooling off. I don't know, I don't know
Speaker 3: why I would have thought that, but that's clearly wrong.
Speaker 3: So I was reading about this in an August first,
Speaker 3: two thousand and one press release from NASA JPL that
Speaker 3: included an interview with a JPL volcanologist named doctor Rosalie Lopez,
Speaker 3: and she says a number of really interesting things in
Speaker 3: this little interview. One of them comes back to that
Speaker 3: sort of designation that people have of Io as the
Speaker 3: most volcanic body in the Solar System. She stresses that
Speaker 3: this is not because Io has the most volcanoes, as in, like,
Speaker 3: you count up all the volcanoes and it has the most.
Speaker 3: Because I actually checked, this Earth has more volcanoes total.
Speaker 3: Earth has more than Io does, but Earth is also larger.
Speaker 3: Of course, the reason that scientists call Io the most
Speaker 3: volcanic body in the Solar System is that its volcanoes
Speaker 3: put out the most total heat. So it's the most
Speaker 3: volcanic because it's a question of total energy released. Io
Speaker 3: is only about one third the size of Earth, but
Speaker 3: it puts out like double the heat of Earth from
Speaker 3: its volcanoes. And Lopez notes that one single volcano on Io,
Speaker 3: known as Loki, is more powerful than every volcano on
Speaker 3: Earth put together. Now, another interesting part in this exchange
Speaker 3: is that the interviewer asks Lopez whether the volcanoes on
Speaker 3: Io would be similar to volcanoes on Earth. How would
Speaker 3: they be similar? How would they be different? And Lopez says, quote,
Speaker 3: the types of eruptions we've observed on Io are similar
Speaker 3: to types of eruptions on Earth. Lava flows, calderas, fire
Speaker 3: fountains like in Hawaii. But there are some very different aspects.
Speaker 3: One is that lava on Io is much hotter than
Speaker 3: any lava that flows on Earth today. Billions of years ago,
Speaker 3: Earth had lava that hot. Another difference is that the calderas,
Speaker 3: the volcanic craters on Io are much larger, than on Earth.
Speaker 3: Lava flows are much larger too, and then she cites
Speaker 3: a volcano on Io named Amirani that has a lava
Speaker 3: flow going three hundred kilometers long or about one hundred
Speaker 3: and ninety miles. She of course notes that that's longer
Speaker 3: than any known lava flow on Earth, but I looked
Speaker 3: up something to try to find a comparison. Three hundred
Speaker 3: kilometers is roughly the distance from New York to Providence,
Speaker 3: Rhode Island, So just imagine an active lava flow that long.
Speaker 3: And then finally, in this answer, she notes that io
Speaker 3: eruptions on Io produce like one hundred times as much
Speaker 3: molten lava per year as eruptions on Earth. And that's
Speaker 3: counting up all of the erupting volcanoes on Earth, even
Speaker 3: the ones under the sea. So that's all amazing. I'm
Speaker 3: especially fascinated by the idea that Earth used to have
Speaker 3: hotter lava, Like we're kind of in decline and our
Speaker 3: planets just like we can't put out lava like we
Speaker 3: used to. But if you take all that together, think
Speaker 3: about like the massive number of erupting volcanoes on Io,
Speaker 3: how much heat they put out, and just like what
Speaker 3: a in some ways boiling world. This is that might
Speaker 3: paint a picture of a hothouse, a sort of planetary
Speaker 3: hell world like Venus, but actually that would not be
Speaker 3: accurate if you're trying to imagine what it's like on
Speaker 3: the surface of Io. Because the apage surface temperature of
Speaker 3: Io is extremely cold. Io has a very thin atmosphere,
Speaker 3: extremely thin sulfur dioxide atmosphere, too thin to trap heat effectively,
Speaker 3: and that's you know, one reason Venus is so hot.
Speaker 3: It's it's because it's got a very thick atmosphere that
Speaker 3: traps heat within the atmosphere. Io does not have that.
Speaker 3: So while it's got these super you know, extremely hot
Speaker 3: hot spots where the volcanoes are erupting or the lava
Speaker 3: flows are taking place. You might have a lake of
Speaker 3: lava that's you know, going to be incredibly hot. Most
Speaker 3: of the Moon is very cold, with an average surface
Speaker 3: temperature of negative one hundred and thirty degrees celsius or
Speaker 3: negative two two fahrenheit, So astronomers sometimes call it a
Speaker 3: like a world of fire and ice. It's a place
Speaker 3: where you have these these gigantic, massive erupting volcanoes and
Speaker 3: giant long lava flows, you know, going New York to Providence,
Speaker 3: Rhode Island. But at the same time you'll have these
Speaker 3: almost whimsic frisky ice world conditions. For example, I mentioned
Speaker 3: the fact that Io has this very thin atmosphere of
Speaker 3: mostly sulfur dioxide. Some of that sulfur dioxide comes directly
Speaker 3: from volcanic eruptions venting screaming hot sulfur from below, but
Speaker 3: the other half comes from the gradual evaporation or technically
Speaker 3: sublimation of vast fields of sulfurous ice already on the
Speaker 3: planet's surface. So there's a pattern that goes like this.
Speaker 3: The volcanoes erupt and they shoot sulfur dioxide into the atmosphere.
Speaker 3: It floats around. Then, once every forty two hours or so,
Speaker 3: Io passes briefly into Jupiter's shadow, so it becomes eclipsed
Speaker 3: and all sunlight is blocked, and this causes the surface
Speaker 3: temperature to drop even further. It causes the Moon to
Speaker 3: temporarily go into a deep cold cold enough to actually
Speaker 3: cause the lower SO two atmosphere level to freeze and
Speaker 3: fall to the surface. Then, when I emerges from its
Speaker 3: eclipse and comes back into the sunlight, the frozen planes
Speaker 3: of sulfur snow start to warm up and sublimate into
Speaker 3: gas once again, which becomes part of the tenuous atmosphere.
Speaker 3: So there's a lot more we'll have to get into
Speaker 3: about the Moon, but just starting with this portrait, this
Speaker 3: sketch here, I really would make the case for Io
Speaker 3: as one of the most interesting places in the Solar System,
Speaker 3: you know, beyond Earth, of one of the most challenging
Speaker 3: and strange and dramatic and fascinating places in all of space.
Speaker 2: Absolutely. Yeah, the closer you look at it than the
Speaker 2: more amazing details there are.
Speaker 3: Now, speaking of dramatic landscapes, I did want to mention
Speaker 3: one more of the images that really got me interested
Speaker 3: in doing the series of episodes. This one actually is
Speaker 3: less a I think, less directly a photograph and more
Speaker 3: kind of an image generated based on It was like
Speaker 3: a three D image that's like an artist concept based
Speaker 3: on data from Juno's Junokam instrument. So it's not just
Speaker 3: made up like it is based on data they took
Speaker 3: from the surface. But it's like a generated three D
Speaker 3: image and it's of iOS steeple mountain that's worth looking
Speaker 3: up at home, folks. It's this mountain that comes up
Speaker 3: out of the surface like a blade. It's just like
Speaker 3: so sharp, and then has the spires reaching up from
Speaker 3: the top of it. And so if you look this up,
Speaker 3: there are sort of animations you can find online where
Speaker 3: the perspective goes around the mountain to sea from its
Speaker 3: day side into its night side and shadow. And it's Oh,
Speaker 3: it's very haunting, especially because it has a strong, lonely
Speaker 3: mountain energy. It's not part of a mountain range. It's
Speaker 3: just one giant blade of mountain raising up out of
Speaker 3: an otherwise relatively flat plane.
Speaker 2: Yeah, with these two spires, one has the appearance of
Speaker 2: being broken. Reminds me of the the horns of Golgadaath,
Speaker 2: two horns coming up out of the ruined earth. So yeah,
Speaker 2: it's pretty evocative.
Speaker 3: But Io is actually full of these strange and gorgeous
Speaker 3: surface features, both the ones that rise and the ones
Speaker 3: that sink.
Speaker 2: That's right. Another interesting feature is Boa Sali Monts. This
Speaker 2: apparently stands as the tallest known peak on Io, standing
Speaker 2: between seventeen point five kilometers that's ten point nine miles
Speaker 2: and eighteen point two kilometers are eleven point three miles
Speaker 2: in height. It is named for the cave where we'll
Speaker 2: get into this. The Greek mythological figure Io is said
Speaker 2: to have given birth to her son. We'll get into
Speaker 2: all that in a bit. And Boa salle means cowpin
Speaker 2: will also get into what that means how cows feature
Speaker 2: into this mythology. But it is the third tallest known
Speaker 2: mountain ridge in our soul system, behind only Olympus monds
Speaker 2: on Mars, which is the tallest, and the equatorial ridge
Speaker 2: on the Saturn nine moon Iapetus.
Speaker 3: Oh yeah, the big spine in the middle of the Appetus.
Speaker 3: That was good.
Speaker 2: Let's see there are a number There are a number
Speaker 2: of other mountains mountains. The mountains on Io have all
Speaker 2: sorts of names, some related, some related to Dante's Inferno,
Speaker 2: some related to other mythological traditions. But there are at
Speaker 2: least four other ones that have names that are related
Speaker 2: to the myth of Io that will get into in
Speaker 2: a bit. There's Argos Planum, named for the land of
Speaker 2: Io's father. There's Epaphus Mensa, named for Io's son, There's
Speaker 2: Hermes Mensa. You'll find out how Hermes factors into everything,
Speaker 2: and then there's Innachius Tholus, name for Io's father. Now,
Speaker 2: you mentioned Loki earlier. This is an of course, the
Speaker 2: namesake is the Norse god Loki, and rather than a mountain,
Speaker 2: it is, of course a great volcanic depression with a
Speaker 2: lake of magma in it. This is a Loki patera.
Speaker 2: As described by the JPL website, this is one hundred
Speaker 2: and twenty four mile long or two hundred kilometer long
Speaker 2: lake filled with magna, rimmed with hot lava, and dotted
Speaker 2: with islands, but with one like huge island in the
Speaker 2: middle of it. And they stress on the JPL website
Speaker 2: that this large island in the lake does not have
Speaker 2: a name, which I think only intensifies the feeling that
Speaker 2: either a it does have some sort of name and
Speaker 2: you just can't say it, or that there is some
Speaker 2: sort of unholy castle there. You know, the island in
Speaker 2: the lake of magma that cannot be named.
Speaker 3: Do not ask after its name, for it has none.
Speaker 2: Yeah, but if they're looking for a name, I'm thinking, well, okay,
Speaker 2: if the area is named for Loki and it's within Loki,
Speaker 2: will name it after one of the monsters that Loki
Speaker 2: gives birth to. I mean, you have, like I think,
Speaker 2: four good ones to choose from there's Hell, there's yormagand
Speaker 2: there's fin Rear, and there's slept Near. But hey, I'm
Speaker 2: no astronomer. Those names may be taken already now. They
Speaker 2: also add that there were reflective aspects to the Loki
Speaker 2: Petera during the Juno flyover, suggesting that its surface was
Speaker 2: as smooth as glass. Now, perhaps smooth as glass in
Speaker 2: these passes, but also food for thought. There's a previous
Speaker 2: twenty seventeen analysis that turned up infrared data that suggested
Speaker 2: that the temperature of the lava lake steadily increased from
Speaker 2: one end to the other, suggesting overturning waves. Overturning lava
Speaker 2: is a popular explanation for fluctuations in the Moon's apparent brightness,
Speaker 2: with brightenings occurring every four hundred to six hundred days.
Speaker 2: Another explanation is that it's due to just regular volcanic
Speaker 2: eruptions that spike the brightness of the Moon.
Speaker 3: I wonder if that's related to different from what Sagan
Speaker 3: brought up about the changes in like the radar reflectivity
Speaker 3: of the of the moon over time.
Speaker 2: I think it's related. That's my understanding, and I am
Speaker 2: for you, Joe. Others can look this up as of publication.
Speaker 2: It's certainly on the JPL website. You can see a
Speaker 2: computer generated image of what this lake would look like,
Speaker 2: and it's this is from like a short computer animated
Speaker 2: video that kind of like zooms in on it, and
Speaker 2: it's it's I like this image because it's it's maybe
Speaker 2: not one hundred percent blockbuster CGI. It feels a little
Speaker 2: you know, mind's eye to me. And also the magma
Speaker 2: in the lake has the coloration of like deep crimson blood,
Speaker 2: which of course only intensifies the the unholy qualities of
Speaker 2: this place. This is just fitting.
Speaker 3: Something seems very beyond the mind's eye about Io. It's
Speaker 3: a place where if I went there, I would expect
Speaker 3: to be seeing like you know, those nude early nineties
Speaker 3: CGI figure is kind embracing and then melting into each
Speaker 3: other and then turning into bats.
Speaker 2: Yeah. All to a nice Jon Hammer soundtrack for sure,
Speaker 2: too far? Take it easy, all right? Well, shall we
Speaker 2: get into the mythology of Io a bit? Oh?
Speaker 3: Absolutely?
Speaker 2: Now, we mentioned already about the discovery of Jupiter's moon Io,
Speaker 2: and we mentioned the discovery sixteen to ten by Italian
Speaker 2: astronomer or Galileo. However, there is also a case to
Speaker 2: be made, and it was made by him, specifically that
Speaker 2: German astronomer Simon Marius discovered it independently or instead of depending.
Speaker 2: He's making the argument.
Speaker 3: I think I've read that it was said like they
Speaker 3: probably discovered it around the same time.
Speaker 2: Yeah, yeah, but Marius is often credited with naming the
Speaker 2: moon after the Greek mythological your Io, who is fittingly
Speaker 2: associated with Zeus aka Jupiter in Roman traditions. Now, if
Speaker 2: you're not familiar with Simon Marius, do look. Do go
Speaker 2: to the Wikipedia page about him, if nothing else, just
Speaker 2: to see this wonderful illustration of the man. This is
Speaker 2: an engraving of Marius in his own book Mundus Lovialis
Speaker 2: the World of Jupiter from sixteen fourteen. He looks like
Speaker 2: a dashing necromancer in this shot.
Speaker 3: Yes, yes, warlock, infernal packed warlock. Actually, though he looks
Speaker 3: a bit this is gonna sound funny. He looks a
Speaker 3: bit like Galileo. Yeah, he's got a similar kind of face,
Speaker 3: a similar kind of eyes and scowl, and a similar beard.
Speaker 3: He's like warlock Galileo.
Speaker 2: Look at that collar though, such an amazing collar packed
Speaker 2: of the lens. All right, So what is the myth
Speaker 2: of Io. Well, the basic story, as it is usually told,
Speaker 2: is as follows. Io was the mortal daughter of Anachus,
Speaker 2: the river god of Argos, and the oceanid Melia, herself
Speaker 2: the daughter of the Titans Oceanus and Tethys. The exact
Speaker 2: number varies, but Io had many sisters, and Anachus also
Speaker 2: is also referenced in mythology as the first king of Argos,
Speaker 2: which is an ancient city in Greece. So the story
Speaker 2: goes that Io served as the high priestess of Hera,
Speaker 2: who is of course the wife of the high king
Speaker 2: of the god Zeus. But the king of the gods
Speaker 2: was of course ever lustful, to put it mildly, and
Speaker 2: soon came to desire Io. Now the story the tellings
Speaker 2: of this tale vary, but at the very least he
Speaker 2: became enamored with her, and some accounts describe his feelings
Speaker 2: for her as love. Avid in the Metamorphosis describes the
Speaker 2: encounter in more threatening and ultimately violent terms. I'm going
Speaker 2: to read from the Henry t Riley translation. Jupiter had
Speaker 2: seen Io as she was returning from her father's stream,
Speaker 2: and had said, O maid worthy of Jove and destined
Speaker 2: to make I know not whom happy in thy marriage,
Speaker 2: repair to the shades of this lofty grove. And he
Speaker 2: pointed at the shade of the grove, while it is warm,
Speaker 2: and while the sun is at his height, in the
Speaker 2: midst of his course. But if thou art afraid to
Speaker 2: enter the lonely abodes of the wild beasts alone, thou
Speaker 2: shalt enter the recesses of the groves, safe under the
Speaker 2: protection of a god, and that a god of no
Speaker 2: common sort. But with me, who hold the scepter of
Speaker 2: heaven in my powerful hand, me who hurl the wandering lightnings,
Speaker 2: do not fly from me. For now she was flying,
Speaker 2: and now she had left behind the pastures of Lerna
Speaker 2: and the Lsayan plains planted with trees, when the God
Speaker 2: covered the earth far and wide with darkness overspreading, and
Speaker 2: arrested her flight and forced her modesty. So to be clear,
Speaker 2: what Avid is describing here is supernatural pursuit and sexual assault.
Speaker 3: Yeah, from what I've read, I think some versions of
Speaker 3: the story describe it as a kind of seduction. Other
Speaker 3: versions describe it as a rape. In this version, I mean,
Speaker 3: either way, we're seeing something that we see a lot
Speaker 3: of Zeus doing in Greek mythology.
Speaker 2: Yeah, yeah, and again it does vary with the tellings.
Speaker 2: I believe there's at least one version where he ultimately
Speaker 2: impregnates her by just touching her with his hand. So,
Speaker 2: as is generally the case, there's no real canon with mythology.
Speaker 2: There are just the more popularized versions of the tale,
Speaker 2: and sometimes those are very much connected to Avid's work
Speaker 2: in the Metamorphosis. So after this has occurred, Zeus transforms
Speaker 2: Io into a cow, a white heifer, in order to
Speaker 2: hide her and his own transgressions from his wife Harah,
Speaker 2: because of course, of course, Harah is too wise for
Speaker 2: any of this, and she knows her husband too well,
Speaker 2: so she almost immediately shows up and begins asking qu
Speaker 2: questions about this beautiful white cow that Zeus is suddenly
Speaker 2: hanging out with, and Ovid writes quote, Jupiter falsely asserts
Speaker 2: that it was produced out of the earth and that
Speaker 2: the owner may cease to be inquired after which, despite
Speaker 2: the horror of the situation setting this up, this line
Speaker 2: has a certain dry comedy to it, and I wonder
Speaker 2: if that was at present in the original writing, or
Speaker 2: if this is like an artifact of translation.
Speaker 3: I read that same line that it was produced out
Speaker 3: of the earth. Yeah, this cow just kind of grew
Speaker 3: out of the ground. That happens sometimes, so he's trying
Speaker 3: to get out of it.
Speaker 2: But Hara, she knows what's up, and so she requests
Speaker 2: this beautiful cow as a gift, and Zeus has no
Speaker 2: choice but to comply, because if he says no, well
Speaker 2: then he's admitting that this is no mere cow. And
Speaker 2: if he just gives it up, well then you know,
Speaker 2: they both know what's going on here. And so he
Speaker 2: gives the cow up to Hara, and Harah entrusts the
Speaker 2: white effort to the protection of the one hundred eyed
Speaker 2: giant Argos panoptis, the all seeing and there are different
Speaker 2: depictions of what Argus looks like. Sometimes he's depicted as
Speaker 2: a giant with eyes all over his body. Other times
Speaker 2: he's depicted as a humanoid or you know, with no
Speaker 2: special features, or as a humanoid with a bunch of
Speaker 2: eyes on or in his head, and in either event,
Speaker 2: not to be confused with Argos. The place that we
Speaker 2: mentioned earlier, this is Argus. So the basic idea is
Speaker 2: Zeus cannot come and get his cow back at this
Speaker 2: point because there is an all seeing giant that is
Speaker 2: watching it at all the time. Sitting on the top
Speaker 2: of a mountain, he can see in all directions at once.
Speaker 2: Nothing is getting past him. And yes, Zeus is king
Speaker 2: of the gods. But I think the idea is that, yes,
Speaker 2: Zeus is all powerful, but if he actually shows up
Speaker 2: to claim the white heffer, then the gig is up
Speaker 2: and he is almost has to admit defeat.
Speaker 3: Yeah, Haro will find out exactly now.
Speaker 2: Now, in the midst of all this, it is said
Speaker 2: that Io is suffering the metamorphosis here is quite miserable
Speaker 2: the way Ava describes it. She has to live as
Speaker 2: an animal, not mistreated by the all seeing giant, but
Speaker 2: also not well loved either, making matters all the more traumatic.
Speaker 2: When she wanders close to the water, which is described
Speaker 2: as the water off her father, her own father and
Speaker 2: her various sisters do not recognize her, at least not
Speaker 2: at first. They see only the white heifer, and eventually
Speaker 2: her father recognizes her and its heartbreaking. And there are
Speaker 2: numerous paintings that explore this scene with like an old
Speaker 2: man having this heart breaking encounter with a white cow. Oh.
Speaker 3: Yeah, so I was trying to tell if that was
Speaker 3: one of the things depicted in there's a painting of
Speaker 3: the second half of this myth that I put in
Speaker 3: our outline by Bartolomeo di Giovanni, who is an Italian
Speaker 3: painter like the end of the fifteenth century. This painting
Speaker 3: is called the Myth of Io, and it's showing a
Speaker 3: bunch of different scenes from it, though we really do
Speaker 3: not get much of a hundred eyed giant in this. Instead,
Speaker 3: Argust just looks like he's like a shepherd.
Speaker 2: Yeah. Sometimes he's just a dude. Other times he's this
Speaker 2: like weird psychedelic giant with eyes all over his body.
Speaker 2: So it just varies.
Speaker 3: But we do see the heifer at various places, at
Speaker 3: one point near the water's edge, so I can't tell
Speaker 3: if that's the part of the myth that's being depicted here.
Speaker 2: This story of like transformation and loved ones not recognized
Speaker 2: you recognizing you in your transformed state reminds me of
Speaker 2: a children's book that came out in nineteen sixty nine
Speaker 2: called Sylvester and the Magic Pebble. Are you familiar with
Speaker 2: this one? Joe?
Speaker 3: Sounds vaguely familiar, but we don't like read this one
Speaker 3: in the house.
Speaker 2: So okay, well, you might have picked up at some
Speaker 2: point because it's heartbreaking as well. It has a magical
Speaker 2: transformation and parents not recognizing their own child in a
Speaker 2: transformed state. But it's a great book. Well, you know,
Speaker 2: won a number of awards, won the Calvacott Metal back
Speaker 2: in nineteen seventy.
Speaker 3: I'll look it up. But okay, so we're in a
Speaker 3: really sad place in the middle of this myth, right right, I.
Speaker 2: Was in a terrible place Zeus. Sometimes it's described as
Speaker 2: if he finds this heart breaking as well, but at
Speaker 2: the very least he tires of being controlled. And what
Speaker 2: does he do? Well, he can't show himself, apparently, so
Speaker 2: he sends Hermes to simply.
Speaker 3: Murder Argus Mercury the hit man here.
Speaker 2: Yes, yes, the harbinger of the gods here, the messenger
Speaker 2: of the gods this time shows up with his Caduceius
Speaker 2: to put the giant to sleep and then slays him
Speaker 2: with the sword and the eyes of Argus then go
Speaker 2: to the tail of the peacock, a symbol of Hara. Oh.
Speaker 3: Interesting.
Speaker 2: Now at this point the white effer can wander free,
Speaker 2: and Harrah sends a gadfly to torment her gadflies are
Speaker 2: li stock biting flies, probably horseflies or bot flies, but
Speaker 2: in Greek mythology they're sometimes employed by the gods elsewhere.
Speaker 2: Zeus was once said to send one to sting Pegasus.
Speaker 2: At one point. This was while Balerifan was riding Pegasus,
Speaker 2: so caused him to fall out of the sky. But
Speaker 2: don't worry. Athena then softened his fall. So anyway, Io,
Speaker 2: in the form of the white cow, basically wanders driven
Speaker 2: by flies sent by the gods, and eventually she is
Speaker 2: driven to Egypt, where she resumes her human form and
Speaker 2: gives birth to a son of Zeus in a cave.
Speaker 2: We mentioned that earlier, and this is Epaphus, who becomes
Speaker 2: king of Egypt, and it said founds the city of Memphis.
Speaker 2: Avid also mentions that Io went on to marry none
Speaker 2: other than APIs or Osiris, who after his death was
Speaker 2: numbered among the deities of Egypt by the name Serapis. Oh.
Speaker 3: Interesting, Yeah, for those not aware, we did serious episodes
Speaker 3: on the Egyptian deity Osiris. When was this like last
Speaker 3: year or the.
Speaker 2: Year before, Yes, sometime in the last couple of years. Yeah,
Speaker 2: And we talked about Si Rapist as a Greco Egyptian
Speaker 2: Syncretic deity based on both of Cyrus and APIs, as
Speaker 2: well as aspects of various other Greek deities. Under Potomaic rule,
Speaker 2: Avid writes Io terrified and madden with dreadful visions, runs
Speaker 2: over many regions and stops in Egypt when Juno, at
Speaker 2: length being pacified, restores her to her former shape and
Speaker 2: permits her to be worshiped there under the name of Isis. Wow.
Speaker 3: Well, that is a fascinating cross cultural backstory, though not
Speaker 3: to imply that the same backstory would actually be understood
Speaker 3: by the people who worshiped Isis in Egypt.
Speaker 2: Right, right, though, of course, the worship of Isis like
Speaker 2: spreads out of Egypt, and then you know how they're
Speaker 2: worshiping Isis in other areas, such as in Greek and
Speaker 2: Roman times. Yeah, maybe they employ some of this, but yeah,
Speaker 2: at this point in our telling of the myth of Io,
Speaker 2: we can appreciate that we're talking about something that is
Speaker 2: probably a Greek and Roman take on the Egyptian throne
Speaker 2: goddess Isis, mother of every Egyptian king. It's worth noting
Speaker 2: that elsewhere in Greek tradition, Isis is also associated with Demeter.
Speaker 2: In either case, the popularity of Isis in Egypt spreads
Speaker 2: over into Greek mythology here. Yeah, Now it can be
Speaker 2: a little confusing though, because I was looking at other
Speaker 2: artistic depictions of Io, and there's one that from the
Speaker 2: first century BCE. It's a fresco from the Temple of
Speaker 2: Isis in POMPEII that depicts Io being received by Isis
Speaker 2: upon her arrival in Egypt. And if you can see
Speaker 2: an image of it here Joe in our notes in
Speaker 2: this Io actually has the horns of a cow as well.
Speaker 3: Yeah, I mean that may not square in some ways
Speaker 3: with what we just talked about it, but that seems
Speaker 3: to me perfectly consistent with the sort of shuffling mix
Speaker 3: and match quality of ancient mythology.
Speaker 2: Yeah. In Egyptomania a History of Fascination, Obsession, and Fantasy
Speaker 2: by Ronald H. Fritz. This is the book I've cited
Speaker 2: on the show before. The author points to the myth
Speaker 2: of Io is one of several examples of contact and
Speaker 2: cultural exchange between Greece and Egypt during the era of
Speaker 2: the New Kingdom. This was between the sixteenth century BC
Speaker 2: in the eleventh century BCE. You know, they're fairly difficult
Speaker 2: travel between the two regions at the time, but there
Speaker 2: was still cultural exchange and other sorts of exchange as
Speaker 2: well well.
Speaker 3: So it's an emotionally powerful myth with interesting cross cultural relevance.
Speaker 3: But this does bring me back to the question of like,
Speaker 3: how does it fit into the planet Jupiter and its moons?
Speaker 3: How do we get from there to hear well?
Speaker 2: Most likely most of it does come down to just
Speaker 2: the Jupiter Zeus association. Marius's choice in naming it Io
Speaker 2: was apparently based on a sixteen thirteen suggestion by Johannes
Speaker 2: Kepler that the Jovian moons all be named for the
Speaker 2: lovers of Zeus, but it's also worth stressing that there
Speaker 2: was apparently there's a connection to be made between mythic
Speaker 2: Io and Earth's own moon, so she has seemingly has
Speaker 2: lunar qualities all her own anyway. According to classicist Peter T.
Speaker 2: Struck in his online Pin State Classics Dictionary, Io is
Speaker 2: the wanderer and is generally explained as a moon goddess
Speaker 2: wandering in the starry heavens. These heavens symbolized by Argus's
Speaker 2: one hundred shining eyes and then her transformation into a
Speaker 2: horned heifer represents nothing other than the crescent moon.
Speaker 3: Oh interesting.
Speaker 2: Yeah, so yeah, the more you look at it, like,
Speaker 2: the myth of Io is ultimately fairly complicated because you
Speaker 2: have all these different, you know, cross culture exchanges bound
Speaker 2: up in it. There's the lunar aspect of it, as
Speaker 2: well as you know, some of these aspects of the
Speaker 2: story that can be troubling and confounding, especially to modern
Speaker 2: readers that are learning about it, you know, across the
Speaker 2: thousands of years of history. All right, on that note,
Speaker 2: we're gonna go ahead and close up this episode of
Speaker 2: Stuff to Blow Your Mind, but we're going to be
Speaker 2: back in a part two on the Moon of Io.
Speaker 2: We'll get into some more curious details about the moon
Speaker 2: in that episode. In the meantime, we'd like to remind
Speaker 2: you all this Stuff to Blow Your Mind is primarily
Speaker 2: a science and culture podcast, with core episodes on Tuesdays
Speaker 2: and Thursdays, short form episodes on Wednesdays and on Fridays.
Speaker 2: We set aside most serious concerns to just talk about
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Speaker 3: Huge thanks as always to our excellent audio producer JJ Posway.
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