Speaker 1: My welcome to Stuff to Blow your Mind from how
Speaker 1: Stuff Works dot com. Hey, welcome to Stuff to Blow
Speaker 1: your Mind. My name is Robert Lamb and I'm Joe McCormick.
Speaker 1: And today we're going to be exploring a ghost light
Speaker 1: of astronomy. So in the past we've done episodes about
Speaker 1: things like the Will of the Whisp, Right, remember that one,
Speaker 1: Robert that was Strange Lights in the Wood. Yeah, that
Speaker 1: was a lot of fun. I really enjoyed it. And
Speaker 1: the thing about things like the Will of the Wisp
Speaker 1: is you have so many sightings of it over the years.
Speaker 1: People claim they see a light over the marsh or
Speaker 1: a light in the swamp or something like that. Um
Speaker 1: that you have to assume it's not just people making
Speaker 1: stuff up. Somebody at some point really did see something.
Speaker 1: But obviously we don't think it's a ghost or a
Speaker 1: spirit or a malevolent blacksmith who died in the swamp
Speaker 1: and now wants to lead people off of cliffs and
Speaker 1: to quicksand uh, those stories are pretty great, but you
Speaker 1: have to assume something is there, right, well, something is
Speaker 1: there that the woods. The woods are filled with various
Speaker 1: some things. I always come back to the star jelly example, right, Uh,
Speaker 1: the the idea that there's a shooting star and someone says, hey,
Speaker 1: I think there's a meteorite out there in the woods.
Speaker 1: I'm going to go find it. And then they start
Speaker 1: going out and they start looking around, poking around in
Speaker 1: a place that they have passing familiarity with but have
Speaker 1: no real expertise. And then as they're poking around, they
Speaker 1: find something strange to them, some sort of gooey substance,
Speaker 1: and it's it's probably, I mean, it certainly is some
Speaker 1: sort of natural occurring is you know, maybe it's Yeah,
Speaker 1: there's a lot of oozy stuff in the woods if
Speaker 1: you poke around enough, and that's what they find. But
Speaker 1: then they think this is the thing, this is the
Speaker 1: goo that fell from the sky, and and so I
Speaker 1: think there there's there's certainly a case to be made.
Speaker 1: I imagine. I discussed this in the Will of the
Speaker 1: Whisp episode, and we both discussed this that we noticed something,
Speaker 1: we have no immediate explanation for it. But then if
Speaker 1: we have some sort of predominant theory to tie into it,
Speaker 1: or some bit of a myth or folklore, then it
Speaker 1: can take on a life of its own. Yeah. Yeah, exactly.
Speaker 1: But then with a lot of this stuff, you do
Speaker 1: actually have to wonder about it in ways that you
Speaker 1: you feel disinclined to, because, like with the Will of
Speaker 1: the Whisp, there are so many reports over the years,
Speaker 1: you think, well, people had to be seeing some kind
Speaker 1: of light. We don't know what it was. We think
Speaker 1: there was a materialistic explanation for it, but we don't
Speaker 1: know what it was, but there must have been something.
Speaker 1: Then again, how often are people seeing Will of the
Speaker 1: Whisp today? What where did all the sightings go? Yeah,
Speaker 1: that's kind of a strange question. If people really were
Speaker 1: seeing something, how come they don't seem to be seeing
Speaker 1: it with nearly the same frequency anymore? And if you're
Speaker 1: if you're intrigued by that question, you should check out
Speaker 1: our Will of the Whisp episode. Will include a link
Speaker 1: to it on the landing page for this episode is
Speaker 1: Stuff to your Mind dot Com. Today we want to
Speaker 1: focus on a totally different type of ghost light, one
Speaker 1: of the most interesting elusive lights in the history of science.
Speaker 1: And this is not something that you would see in
Speaker 1: the Mars shore. This fickle, unexplained light in the swamp.
Speaker 1: This is a fickle, unexplained light that astronomers have claimed
Speaker 1: to see through the vast reaches of outer space on
Speaker 1: the surface of another planet. Now, to be clear, we're
Speaker 1: not talking about seeing it, just gazing up into the
Speaker 1: sky and seeing it. We're talking about using a telescope, right,
Speaker 1: because obviously planets other than I don't know if you
Speaker 1: call the Moon a planet, things out there other than
Speaker 1: the Moon and the Sun resolved to a kind of
Speaker 1: point like light source for the naked eye, right. And
Speaker 1: and of course we're all familiar with the various strange
Speaker 1: lights one can observe in the sky. Uh, and then
Speaker 1: attribute to any number of of natural or appearing normal
Speaker 1: or causes. Yeah, we're not talking about UFOs or anything
Speaker 1: like that. We're gonna be looking at a planet in
Speaker 1: our Solar system. So I want to start off this
Speaker 1: mystery hunt by introducing you to a seventeenth century Italian astronomer,
Speaker 1: and his name was Giovanni Batista Riccioli. He lived fIF
Speaker 1: to sixteen seventy one. And Riccioli was a Catholic priest
Speaker 1: and an astronomer working in the generation after Galileo. So
Speaker 1: this was a great time of innovation and progress in astronomy. Right,
Speaker 1: So you've had Galileo's strong case made for the Copernican cosmology, right,
Speaker 1: and you've had Galileo improving telescope optics and and so
Speaker 1: the people working at this time to appear into the
Speaker 1: night sky had a lot of new ideas and a
Speaker 1: lot of new technology available to them, better able to
Speaker 1: see and model observable universe exactly. Riccioli was also a
Speaker 1: very important lunar astronomer, and he made detailed maps of
Speaker 1: the Earth facing side of our moon. As we know,
Speaker 1: the Moon is tidally locked with planet Earth, so we
Speaker 1: always see the same side of the Moon, and that
Speaker 1: side has a bunch of topographical features like seas and craters,
Speaker 1: and so a lot of the names of the features
Speaker 1: on the surface of the Moon come from Riccioli's original nomenclature,
Speaker 1: like the Sea of Tranquility and so forth. But on
Speaker 1: January nine three, richili was examining the planet Venus through
Speaker 1: a telescope when it was in its crescent phase. So
Speaker 1: what does it mean for Venus to be in a
Speaker 1: crescent phase. The easiest point of comparison for this would
Speaker 1: be our moon, right, which goes through phases of its own.
Speaker 1: You've got full moon, give us crescent new moon. Uh.
Speaker 1: And of course the moon orbits around the Earth, and
Speaker 1: as it does, it's always day on the side of
Speaker 1: the moon facing the Sun and night on the side
Speaker 1: of the moon facing away from the Sun. And so
Speaker 1: the type of moon we see depends on how much
Speaker 1: of the day versus night side of the moon we
Speaker 1: see facing the Earth. So when the moon is between
Speaker 1: the Earth and the Sun, we're looking at the dark
Speaker 1: nighttime side of the moon, and we get a new moon.
Speaker 1: And when the moon is on the opposite side of
Speaker 1: the Earth from the Sun, we're seeing the bright daytime
Speaker 1: side of the moon, so we get a full moon.
Speaker 1: We're always looking at the same side of the moon,
Speaker 1: but it but sometimes it's day, sometimes it's night on
Speaker 1: that side that we can see. Uh. And then of
Speaker 1: course in between those phases there there are crescents and
Speaker 1: stuff like that. So a crescent moon happens when the
Speaker 1: half of the moon facing us contains mostly the moon's
Speaker 1: night side and then a little sliver of the lid
Speaker 1: up day side. Now, of course, Venus isn't orbiting Earth, right,
Speaker 1: so the timing of these phases is somewhat different, but
Speaker 1: the same basic principles apply Venus orbits the Sun on
Speaker 1: a different schedule than we do. So when Venus is visible,
Speaker 1: sometimes the side facing Us is mostly the bright daytime
Speaker 1: side which reflects a lot of sunlight and looks very
Speaker 1: bright in the sky. And other times when Venus comes
Speaker 1: sort of between the Earth and the Sun. As you
Speaker 1: can imagine if you picture this, the Venus orbits inside
Speaker 1: the Earth's orbit, so it sort of comes between the
Speaker 1: Earth and the Sun. The side facing Us is mostly
Speaker 1: or entirely the darkened night time side of Venus that's
Speaker 1: facing away from the Sun. And Robert, I bet you've
Speaker 1: heard about this before. But of course the phases of
Speaker 1: Venus play a role in the history of establishing how
Speaker 1: the Solar system works, right like this was a point
Speaker 1: of contention for Galileo and and his critics during during
Speaker 1: the time he was alive. Yeah, I mean, this is this,
Speaker 1: this all it makes for a major advancement just celestial mechanics,
Speaker 1: just understanding how the planets in our Solar system are
Speaker 1: moving exactly because the first time we actually know of
Speaker 1: that the phases of Venus that seeing it as so
Speaker 1: sort of more darkened or more or more bright and
Speaker 1: more daytime side. Uh. The first time these phases were
Speaker 1: observed through a telescope and described was by Galileo, and
Speaker 1: this was in the early sixteen hundreds, and at the
Speaker 1: time the phases of Venus were more than a curiosity.
Speaker 1: They were a kind of brutal line of evidence against
Speaker 1: the Ptolemaic geocentric model of the universe. And the reason
Speaker 1: for this is that Galileo showed with the telescope you
Speaker 1: could look at Venus and that it had phases just
Speaker 1: like our moon. But he observed the unlike our moon,
Speaker 1: Venus had a full phase when it was roughly in
Speaker 1: the same direction in the sky as the Sun. So
Speaker 1: think about that. You're looking toward Venus and it's in
Speaker 1: pretty much the same direction as the Sun, but the
Speaker 1: side we can see of it is all lit up
Speaker 1: and bright. The Moon's never like that. When the moon's
Speaker 1: in the same direction as the Sun, the side of
Speaker 1: it we can see as dark. So if all of
Speaker 1: the planets in the Sun went around the Earth, how
Speaker 1: would it be possible for Venus to appear full to us,
Speaker 1: lit up in daytime side when it's in the same
Speaker 1: direction as the Sun. It couldn't were forced to to
Speaker 1: reevaluate the entire structure of our our solar system. Exactly. Yeah,
Speaker 1: So what this showed was that Venus, because it showed
Speaker 1: a full phase at the same time that it was
Speaker 1: in the same direction as the Sun, it couldn't be
Speaker 1: between the Earth and the Sun. It had to be
Speaker 1: on the other side of the Sun from Us, which
Speaker 1: meant that Venus was not orbiting Earth, it was opening
Speaker 1: the Sun. And so Galileo first published this argument in
Speaker 1: his sixteen thirteen Letters on Sun Spots, which was a
Speaker 1: sort of a series of letters that he turned into
Speaker 1: a pamphlet, and which turned out to be the first
Speaker 1: place Galileo actually officially endorsed the Copernican model of the
Speaker 1: solar system, in which the planets go around the Sun
Speaker 1: instead of everything going around the Earth. And of course
Speaker 1: we all know that this was kind of a this
Speaker 1: was rather a controversial theory at the time. It it
Speaker 1: was not well received by by some powerful individuals. Yeah, exactly.
Speaker 1: I mean this put Galileo on course to have extreme
Speaker 1: conflicts with both the scientific and religious hierarchies of the day. Uh. People,
Speaker 1: people forget that it wasn't just the church that was
Speaker 1: persecuting Galileo. I mean a lot of his scientific colleagues,
Speaker 1: I just thought he was wrong for reasoning, you know,
Speaker 1: for reasons of their own. Yeah, and there were a
Speaker 1: lot of people that were very invested in the previous model.
Speaker 1: He's really changed everything, whether you were looking up at
Speaker 1: the stars with a with a more of a scientific
Speaker 1: mindset or or a purely religious one exactly. But anyway,
Speaker 1: so when an astronomer looks at Venus in its crescent phase,
Speaker 1: they're seeing mostly the night side of Venus, right, and
Speaker 1: so you've got this sliver of daytime that's separated by
Speaker 1: what's known as the terminator line. The terminator line is
Speaker 1: the boundary between the night side and the day side
Speaker 1: on the surface of a planet. And if you've never
Speaker 1: seen this, it can be very haunting, Like if you
Speaker 1: view the terminator line on Earth from the International Space Station.
Speaker 1: There are videos of this you can look up online
Speaker 1: where the station is rapidly orbiting the Earth. You see
Speaker 1: the ground beneath passing along and it's the daytime side
Speaker 1: of the planet and suddenly this curtain of dark just
Speaker 1: sweeps over the face of the planet. Uh. It's it's
Speaker 1: kind of terrifying to see actually but also very beautiful.
Speaker 1: It's it's worth looking up alright. So so we're looking
Speaker 1: up at the night side of Venus here gazing into
Speaker 1: the dark, just into the dark on another planet, right,
Speaker 1: What is the curious incident of the Venus in the
Speaker 1: night So on that j Your evening sixteen forty three,
Speaker 1: Richie Ali's looking at Venus through his telescope in this
Speaker 1: crescent phase where there's a small crescent limb of light
Speaker 1: and there's the terminator line, and most of Venus should
Speaker 1: be dark. The crescent portion was at roughly thirty percent
Speaker 1: of the planet when when Richieli was looking at it. Now,
Speaker 1: when you look at Venus in a crescent phase like this,
Speaker 1: the nighttime side of the planet is supposed to be
Speaker 1: completely invisible. It's so dark compared to the brightly lit
Speaker 1: up crescent of the daytime side that you shouldn't be
Speaker 1: able to see it at all. The daytime sliver of
Speaker 1: the planet should be like a bright melanrind floating in
Speaker 1: space by itself with nothing else there. But when Richili
Speaker 1: looked at it that January evening in sixty three, something
Speaker 1: was not right. Instead of a bright crescent and an
Speaker 1: invisible nighttime side, Richie Eli believed he saw something startling,
Speaker 1: a very faint glow coming from the dark side of Venus.
Speaker 1: The side of Venus where it was currently night time
Speaker 1: appeared to be ever so faintly shining gray light into space.
Speaker 1: And Richie Eli gave this glow a name. He called
Speaker 1: it the ashen Light of Venus. Spooky. Huh, yeah, it
Speaker 1: has it has it certainly has an anonymous ring to it. Yeah,
Speaker 1: it's It's funny. How if you just give something a
Speaker 1: really good name, it'll end up getting a lot more
Speaker 1: attention than something that doesn't have a good name. Uh
Speaker 1: And and I think that's probably the case here. The
Speaker 1: ashen light, I think maybe gets more attention from amateur
Speaker 1: astronomers trying to find it and stuff like that than
Speaker 1: a similar observation would be if it was just called
Speaker 1: something very mundane. It sounds like a like like a
Speaker 1: new metal album from from the early two thousands, so
Speaker 1: people were like, yeah, let's look for that ashen light.
Speaker 1: I'm pretty sure there is a is a metal band
Speaker 1: called Ash and Light. You just know it happens, right,
Speaker 1: It's like there's nothing left. The metal bands have scoured
Speaker 1: the earth. It's like going through a post apocalyptic wasteland
Speaker 1: has been picked clean of every bit of canned food
Speaker 1: and ammunition and everything you think you might want. If
Speaker 1: there's an idea or an ordering of words that sounds cool,
Speaker 1: it has been scavenged by a metal band in Ohio somewhere.
Speaker 1: I don't know. I have a feeling that before we
Speaker 1: make it through this this episode will have found something
Speaker 1: that some fledgling metal band can latch onto and embraces
Speaker 1: their name. But anyway, the Action Light itself. So Ever,
Speaker 1: since Riccioli's original sighting, other astronomers, both professional and amateur,
Speaker 1: have been looking for the Action Light, and a lot
Speaker 1: have claimed to see it, but many others have looked
Speaker 1: when it should be visible and found nothing. So this
Speaker 1: controversy exists. Does the Action Light really exist? And if
Speaker 1: it does exist, what is it? What is making the
Speaker 1: night time side of Venus glow? On that note, we're
Speaker 1: going to take a quick break, and when we come
Speaker 1: back we will discuss subsequent sightings or claims of sightings
Speaker 1: of the Action Light and some ideas about just what
Speaker 1: it could be. Alright, we're back. So we've been discussing
Speaker 1: Giovanni Batista Riccioli's original sighting of what he thought was
Speaker 1: the action light on the night side of Venus in
Speaker 1: sixty three, and here's how he described it. So he said,
Speaker 1: it appears to be a dull, faint glow, some sort
Speaker 1: of gray, somewhat like earth shine on the dark side
Speaker 1: of the moon. Now what is earth shine. That's when
Speaker 1: the moon is in a crescent phase, meaning most of
Speaker 1: the moon's sunlit day side is facing away from Earth
Speaker 1: and most of the moon's darkened night side is facing
Speaker 1: towards Earth, and light from the Earth shines on the
Speaker 1: night time side of the Moon to produce a soft, gray,
Speaker 1: glowing reflection. But the action light is allegedly even fainter
Speaker 1: than the earth shine on the moon. Because we know
Speaker 1: the earth shine on the moon exists, we've got evidence
Speaker 1: of that that the action light is still controversial. So
Speaker 1: you've got all these claims of sighting this of this
Speaker 1: dull brownish or copper or gray light on the other
Speaker 1: side of Venus. Now where do some of these sightings
Speaker 1: come from? One of them was by William Durham in
Speaker 1: seventeen fourteen, so that was apparently the next sighting after
Speaker 1: richie Oli. Uh seventeen fourteen, the English natural philosopher William
Speaker 1: Durham was observing Venus through a telescope and he called
Speaker 1: the light a dull, rusty color. Then you had actually
Speaker 1: a big name in the history of astronomy, the German
Speaker 1: born British astronomer Sir William Herschel. Oh yeah, yeah, nature
Speaker 1: name there. So he lives seventeen thirty eight to eighteen
Speaker 1: twenty two. And Herschel was the discoverer of Uranus in
Speaker 1: seventeen eighty one, which was extremely significant because I think
Speaker 1: a lot of people don't really It's got a mythological name,
Speaker 1: right like the other planet. So a lot of times
Speaker 1: I think people assume that Uranus was known about by
Speaker 1: the people who believed in the god Uranus or Uranus
Speaker 1: like I guess, however you say it, both both are correct,
Speaker 1: just once more funny solistic with Uranus. But yeah, the
Speaker 1: Uranus was actually discovered in sev one. It was. This
Speaker 1: was extremely significant because it was the first discovery of
Speaker 1: a new Solar System planet since ancient times. The ancients
Speaker 1: had been able even before telescopes, to see planets like
Speaker 1: Jupiter with the naked eye, so to be clear at
Speaker 1: this point, we've we've already established there's not just one
Speaker 1: individual who saw it, and it's not just uh, and
Speaker 1: and and and Also we're talking about like noted astronomers
Speaker 1: of of their day here, not near amateurs who just
Speaker 1: happened to pick up a telescope and and gaze hopefully
Speaker 1: up at Venus to see what they could see. No,
Speaker 1: these were respected astronomers and observers of the sky. These
Speaker 1: are people who we can talk about this more in
Speaker 1: a minute. But there are people who you wouldn't expect
Speaker 1: to be hoaxing. You know. It's not like somebody is
Speaker 1: just like, oh, yeah, yeah, yeah, I saw a willow,
Speaker 1: the whisp and the swamp. Yeah it was great. But
Speaker 1: then to be clear too, whereas the willow will of
Speaker 1: the whisp already has like supernatural connotations to it, this
Speaker 1: was more of a purely scientific observation without getting into
Speaker 1: some of the possible reasons that could be attached to it. Uh,
Speaker 1: just gazing at another planetary body and and and seeing
Speaker 1: some sort of illumination or seeing just anything, any kind
Speaker 1: of phenomena that they could not be easily explained. I mean,
Speaker 1: that's kind of part for the course of gazing up
Speaker 1: at other planets. I mean, I would be shocked if
Speaker 1: over the years, somebody at some point didn't claim that
Speaker 1: the ashen light was caused by I don't know, the
Speaker 1: fires of hell burning on the surface of Venus where
Speaker 1: all the damned and heretics went. I mean, just think
Speaker 1: of Herschel for example, here like which is the crazier thing,
Speaker 1: Which is the bigger moment in his life? Yeah, I
Speaker 1: saw some of this light that this other guy was
Speaker 1: talking about. I saw it on on the dark side
Speaker 1: of Venus, versus I've discovered a new planet. Yeah, he
Speaker 1: don't planet exactly. That's a good point. He didn't need
Speaker 1: to be like a tension seeking or anything. There's no
Speaker 1: reason really for Herschel to claim to see this without
Speaker 1: actually seeing it, though of course he could be mistaken
Speaker 1: about seeing right, And when we're discussing it in hindsight,
Speaker 1: the action light is more of a mystery, yeah, versus
Speaker 1: the the the awe that would have been associated with
Speaker 1: discovering a new planet. Because, like you say, we've known
Speaker 1: of of Uranus our entire lives. It's just it's one
Speaker 1: of the planets to memorize, and we often fall into
Speaker 1: the traffic, just thinking that humans have known about it
Speaker 1: for ages. Yeah, exactly. Uh so. Another observer in the
Speaker 1: nineteenth century Thomas William Webb in eighteen seventy eight. He
Speaker 1: was a British astronomer. He was a reverend, and he
Speaker 1: claimed he saw the light in eighteen seventy eight on
Speaker 1: January thirty one, with a two hundred and thirty eight
Speaker 1: millimeter reflector, so you know, mirror based telescope. And he
Speaker 1: writes quote on January thirty feet after having many times
Speaker 1: looked for it in Vain in former years, I saw
Speaker 1: it without specially thinking about it, with powers of about
Speaker 1: ninety and two twelve on my nine point three at
Speaker 1: inch or two hundred two hundred and thirty eight millimeter mirror,
Speaker 1: coming out at intervals rather paler and browner than the
Speaker 1: twilight sky, and equally visible when the bright crescent was
Speaker 1: hidden by a field bar. Now, this field bar, or
Speaker 1: sometimes called an occulting bar, would be a device that
Speaker 1: essentially blocks something bright so that you can see dimmer
Speaker 1: things better. In this case, it would block out the
Speaker 1: crescent on Venus, because that's the daytime side is very bright,
Speaker 1: and that would allow you to see whether there's something
Speaker 1: visible on the nighttime side by eliminating the glare. And
Speaker 1: I also want to point out for anyone who lacked
Speaker 1: unto the fact that this guy was a reverend um
Speaker 1: a number of these sort of gentlemen scientists of the
Speaker 1: of the day. Uh, we're also religious individuals as well,
Speaker 1: so that's not really that uncommon. Oh yeah, Especially in
Speaker 1: the history of astronomy, you see tons of astronomers who
Speaker 1: were affiliated with, for example, the Catholic Church, or with
Speaker 1: the Church of England or something like that. Another astronomer
Speaker 1: named C. V. Zinger of Prague said he observed the
Speaker 1: ghost slide of Venus in January eight eighty three and
Speaker 1: that the disc of the planet was quote splendidly visible.
Speaker 1: The most important feature of the observation was the ring
Speaker 1: that I could detect all around the disk dark part
Speaker 1: and crescent of brownish red color more pronounced on the
Speaker 1: illuminated side than on the dark part of the limb,
Speaker 1: but of a peculiar coppery hue. And then of course
Speaker 1: there were many reported sightings in the twentieth century. A
Speaker 1: bunch of sightings in nineteen fifty three with independent observers
Speaker 1: claiming to see the light at the same time in
Speaker 1: different locations. Uh. There were also a number of alleged
Speaker 1: sightings in nineteen fifty six and fifty seven. Also, I
Speaker 1: think I read about sightings in nineteen forty and I
Speaker 1: think on all in all these years I mentioned there
Speaker 1: were sightings on consecutive nights reported to the British Astronomical Association.
Speaker 1: But already we can see that if something is occurring,
Speaker 1: if there actually is a light there, it's not it's
Speaker 1: not there all the time, right, Yeah, So this is
Speaker 1: something that's going to contribute to the mystery and maybe
Speaker 1: help us reason about if it really exists what it is. Um,
Speaker 1: Now you may be noticing so far that we're all
Speaker 1: talking about visual sightings, not about capturing images of it.
Speaker 1: Now that that'll that will play into our discussion. In
Speaker 1: a minute, just to mention a couple more sightings real quick.
Speaker 1: Um and Dale Crookshank, a planetary scientist at NASA Ames
Speaker 1: Research Center, and William K. Hartman, another planetary scientists, they
Speaker 1: observed Venus at inferior conjunction. Now that conjunction is when
Speaker 1: planets line up in a line, So inferior conjunction would
Speaker 1: be when the Earth Venus and the Sun line up together,
Speaker 1: with Venus on the same side of the Sun as
Speaker 1: the Earth. I guess obviously it would have to be
Speaker 1: on the same side of the Sun as the Earth
Speaker 1: if we're observing it now. The thing here that I'm
Speaker 1: sure it's jumping out at everyone though, as we mentioned
Speaker 1: these dates, is that none of these dates are particularly recent,
Speaker 1: and it's it's easy to just assume that. Okay, as
Speaker 1: as as our technology increases, is our ability to view
Speaker 1: and capture images of venous increases. If sightings go down,
Speaker 1: then that's that's a huge red flag. It absolutely is.
Speaker 1: That's a very good point in something that other astronomers
Speaker 1: uh we we will talk about later in the episode,
Speaker 1: have pointed out. But yeah, it seems that while there
Speaker 1: have been all these numbers of sightings, sightings apparently get
Speaker 1: more rare as our ability to capture faint images with
Speaker 1: astronomical equipment becomes better. Uh So, uh Dale, Dale Crookshank,
Speaker 1: and William Hartman that I mentioned a minute ago, they
Speaker 1: did not capture an image of it. They drew an
Speaker 1: image of it based on their visual observations. Um. They
Speaker 1: said that the circle of the disk within the ring
Speaker 1: of light glowed to kind of dull brown color, and
Speaker 1: they said that this was a different color from the
Speaker 1: blue sky behind the planet, and that the color difference
Speaker 1: seemed to be the strongest near the crescent. And so
Speaker 1: I added an illustration of what they think they saw. Robert, Now,
Speaker 1: it looks kind of like if there's a bright ring
Speaker 1: and then inside it there's just a slight, slight hue
Speaker 1: of brown, right right, And now trying to include this
Speaker 1: image on the landing page for this episode of Stuff
Speaker 1: to Plow your Mind dot Com so that people can
Speaker 1: can see what we're talking about as well. Just one
Speaker 1: more alleged siding, the English astronomer Sir Patrick Moore, who
Speaker 1: passed away unfortunately in two thousand twelve. He claimed to
Speaker 1: have seen the ash and light many times throughout his career,
Speaker 1: including a siding in nineteen eighty that he regarded as
Speaker 1: sort of unmistakable, in which he described as looking like
Speaker 1: earth shine on the moon. Now, despite all of these
Speaker 1: claims of observations, as we've been discussing, there is emerging
Speaker 1: a pattern of like questions that somebody skeptical of this
Speaker 1: phenomenon should should be asking, right, the British astronomers Dr
Speaker 1: Paul Abel and Pete Lawrence, writing for BBC Sky at
Speaker 1: Night magazine right about how part of the problem with
Speaker 1: the ash and light is that all the claimed sidings
Speaker 1: over the years have just been people claiming to see
Speaker 1: it directly with their eyes through the eyepiece of the telescope,
Speaker 1: and no one has ever captured a good, really unmistakable
Speaker 1: photo or digital image of the glow. And they discuss
Speaker 1: how lots of astronomers have searched for the low over
Speaker 1: the years and never been able to see it, despite
Speaker 1: earnest attempts many many years in a row. For example,
Speaker 1: the famous American astronomer Edward Emerson Barnard tried to see it,
Speaker 1: but he never could And the authors themselves at the
Speaker 1: time of writing claimed they've never been able to see
Speaker 1: the ash and light. Yeah, all you have here is
Speaker 1: observation data. You have no like like hard measurements of
Speaker 1: it based I mean, besides what can be made with
Speaker 1: the human eye and then recorded, which opens it up
Speaker 1: to a number of different errors in cognition and memory
Speaker 1: encoding that can occur. And really you have to realize
Speaker 1: to here, that's like most people that are looking at
Speaker 1: venus do not see it. Only some people are seeing it.
Speaker 1: Some people are arguably good at seeing it, whereas others
Speaker 1: are are less skilled at seeing the ash and light. Now,
Speaker 1: to be fair to proponents of the ash and light,
Speaker 1: it's it seems to be part of the phenomenon. If
Speaker 1: it is real, that it is infrequent, like it only
Speaker 1: appears at certain times, and we could discuss later what
Speaker 1: could cause that. If it really is a is an
Speaker 1: actual glow coming from the planet and not just a
Speaker 1: trick of the eye. Uh So, I guess before we
Speaker 1: get into explaining what it could be if it is real,
Speaker 1: we should explain what could cause all these sightings if
Speaker 1: it is not real. One of the things you always
Speaker 1: have to consider, of course, is the possibility of a hoax.
Speaker 1: But that really doesn't seem very likely to me in
Speaker 1: this case, because you've got so many reports from very
Speaker 1: apparently serious people over the years. Um, like, this wasn't
Speaker 1: a ghost reported by some drunk high schoolers in a
Speaker 1: in a swamp or something. No, But but I think
Speaker 1: it is important to realize that seeing a UFO whilst
Speaker 1: drunk in the swamp is exactly the kind of thing
Speaker 1: that a that a that a that a non scientist
Speaker 1: might see, but seeing an astronomical detail that other experts
Speaker 1: have reported over the years. I mean, that's the kind
Speaker 1: of thing that an astronomical observer might uh want to see, right,
Speaker 1: Oh yeah, yeah, I I certainly think that they could
Speaker 1: the people seeing it could be mistaken. Well, I was
Speaker 1: going to mention that in a second, but I'm trying
Speaker 1: to rule I don't think it's deliberate hoax. That that
Speaker 1: seems like it doesn't fit. Uh, you know, why would
Speaker 1: William Herschel be participating in a deliberate hoax and all
Speaker 1: these different people over the years. It just doesn't does
Speaker 1: not seem like a good explanation to call this wilful misrepresentation. Now,
Speaker 1: on the other hand, observer error is a very strong candidate.
Speaker 1: As as you're talking about Able and Lawrence right in
Speaker 1: their article quote, it's reasonable to suppose that under certain conditions,
Speaker 1: the brilliant crescent of Venus, combined with poor seeing tricks
Speaker 1: the human eye into thinking it can see the night
Speaker 1: side of Venus when in reality it is not visible. Now,
Speaker 1: we've talked before about different kinds of optical illusions on
Speaker 1: the show, and a very common kind of optical illusion
Speaker 1: is a kind of completion effect of the eye. Right,
Speaker 1: you see part of a figure, and the brain knows
Speaker 1: what the rest of the figure should look like and
Speaker 1: kind of seese it. Because our brain, our vision is
Speaker 1: not a camera or a video recording device. No, our
Speaker 1: vision is cognitive. It is a cognitive process. And and
Speaker 1: therefore it's not just our brains are not just seeing
Speaker 1: what we're seeing. Our brains are forming the picture of
Speaker 1: the world that our eyes are helping us to to
Speaker 1: take in. Yeah, so you see with your eyes, but
Speaker 1: you also see with your emotions, and you see with
Speaker 1: your memory, and you see with your biases. These these
Speaker 1: actually affect what you see. Like you say, Robert, it's
Speaker 1: not just a totally neutral device taking pictures of things
Speaker 1: and recording different light levels at each pixel spot. Yeah.
Speaker 1: I'm instantly reminded of times that I've looked at, say,
Speaker 1: you know, a three D image one of these of
Speaker 1: what were they called? They they had whole books off them,
Speaker 1: and you had to sort of stare magic I have
Speaker 1: the magic Eye books, and uh, some of those I
Speaker 1: could see fairly easily, but others that would just stare
Speaker 1: at and stare at, and then you reach a point
Speaker 1: where you're like, do I see it? I think maybe
Speaker 1: I see it. I kind of want to stop staring
Speaker 1: at it, but maybe I see it. Um maybe this
Speaker 1: means there's something wrong with my brain. But I was
Speaker 1: never able to see those things. Well, this could be
Speaker 1: something we explore in a future episode, like why why
Speaker 1: do some people see the Magic Eye things more more
Speaker 1: readily than others? Um Or is it? Maybe it's all
Speaker 1: a hoax. Maybe there's there's nothing there. But if you
Speaker 1: stare at it long enough and people were expecting you
Speaker 1: and priming you to see these images, then you eventually say, yes,
Speaker 1: it's a tiger. Clearly, the Emperor has no clothes. The
Speaker 1: magic Eye is fake. There is no tiger. It's all
Speaker 1: just gibberish. Everybody's like, oh, yes, yes, I see the fleas.
Speaker 1: I mean, I've also had that situation with I mean
Speaker 1: and being a little glimp here about the magic Eye.
Speaker 1: But I've had that situation with the attempt to observe
Speaker 1: something supernatural, the like the the desire to say, see
Speaker 1: a spaceship, you know, as a kid, like look up
Speaker 1: at the stars and and maybe you know you're afraid
Speaker 1: to see something, but you also you just want to
Speaker 1: see something staring into the woods and hoping to see
Speaker 1: a ghost, that kind of thing. And I never did
Speaker 1: see anything of that nature, um in either case. But
Speaker 1: there's this you can feel the straining at time, like
Speaker 1: like do I see something? Do I see something? Like
Speaker 1: it almost like you're pushing yourself up to that line
Speaker 1: of telling yourself you see something. Uh you know whether
Speaker 1: you're willing to actually cross that line, uh you know
Speaker 1: or not. But it's not. But I don't think that
Speaker 1: line is necessarily a situation of today. I shall make
Speaker 1: something up today, I will will create the story of
Speaker 1: how I saw a UFO. I feel like that's a
Speaker 1: line that we that we sometimes creep up to. Oh
Speaker 1: and then suddenly you're standing on the other side of it.
Speaker 1: I know exactly what you're talking about. Yeah, yeah, yeah,
Speaker 1: I mean it's like, uh, it's like listening for the
Speaker 1: sounds of ghosts whispering in an echoeek cathedral, Like you
Speaker 1: know your you might not be likely to hear that
Speaker 1: if you just stand there listening, But if you're trying
Speaker 1: to hear a ghost speaking in a cathedral, you might
Speaker 1: not think that you're making it up, but you will
Speaker 1: be sensitive to kind of anomalous and m pops and
Speaker 1: sounds that you can apply your cognitive filters too and
Speaker 1: make something out of. Yeah, and we've discussed before in
Speaker 1: the show how you know, we've already talked how the
Speaker 1: brain is sort of filling in the blanks of vision,
Speaker 1: and when we are presented with limited stimuli, be it
Speaker 1: auditory or visual, the brain can kind of create, uh,
Speaker 1: patterns where there are no patterns. It can create a
Speaker 1: voice where there is no voice, a sound where there
Speaker 1: is no voice. And and ultimately you're talking about astronomical
Speaker 1: data that is limited visual stimuli. That's right, But then again,
Speaker 1: I I also don't want to go over the edge
Speaker 1: and be too dismissive because you've got a lot of
Speaker 1: reports over the year. There's a lot of undeniable And
Speaker 1: again getting back to that that very important point that
Speaker 1: whatever it is, we're just if we were just to assume, yes,
Speaker 1: there is was an action light on venus, like you said,
Speaker 1: it is clearly not observable all the time, so it's
Speaker 1: not something that can be is regorously tested, as say,
Speaker 1: the the idea of canals on Mars, which we'll get
Speaker 1: to in a bit, right, So if it does cist,
Speaker 1: I think we should transition to talk about, if it
Speaker 1: does exist, what could explain it? What would match the
Speaker 1: descriptions people see, what kind of light could be shining
Speaker 1: off of the night time side of venus uh And
Speaker 1: I think clearly, clearly the best explanation for the ashen
Speaker 1: light comes to us from the Bavarian astronomer and physician
Speaker 1: Franz Vonpaala Growthhausand uh from who he lived from seventeen
Speaker 1: eighteen fifty two. And he was you know, it seems
Speaker 1: to me he wasn't a dummy, but he was obsessed
Speaker 1: with space aliens. Oh yeah, he was. He was the
Speaker 1: real deal. He was a major contributor of the day
Speaker 1: to fields of urology and lithotrity, which is the treatment
Speaker 1: and removal of gall stones, bezors, and kidney stones. We
Speaker 1: we discussed all three of these on our Stone of
Speaker 1: Madness episode did a few years back. Uh So he
Speaker 1: developed key technologies that helped make bladderstone removal safer and
Speaker 1: less likely to result in the horror rible death of
Speaker 1: the patient. As we discussed in that Stone of Madness episode,
Speaker 1: not only were kidney stones painful ordeals, but the methods
Speaker 1: of treating and removing them, but they had the other
Speaker 1: days were just barbaric. Uh. So there was a very
Speaker 1: high mortality rate for surgical intervention and growth thousand helped
Speaker 1: change that. He helped establish the technologies that allowed the
Speaker 1: uh these fields to evolve and for people to uh
Speaker 1: to to engage in the treatment of of of various
Speaker 1: stones without without facing down death quite as often. So
Speaker 1: so real physician, not a dummy, Yeah, not a dummy.
Speaker 1: He was highly influential in his field. During his life.
Speaker 1: He went on to write hundreds of scientific articles and
Speaker 1: a number of books that covered various topics in the
Speaker 1: field of natural sciences. So he was, you know, he
Speaker 1: was something of a renaissance man in that regard, and
Speaker 1: he was he was a legit astronomer. Yeah. He became
Speaker 1: professor of astronomy at the University of Munich in eighteen
Speaker 1: twenty six. So again, very bright guy. Uh, No mere amateur.
Speaker 1: He didn't just pick up a telescope and say, hey,
Speaker 1: I see the ash and light. I'm going to write
Speaker 1: a book about it. Uh. He knew what he was
Speaker 1: talking about. But at the same time, I think it
Speaker 1: could definitely be argued that he he engaged with uh,
Speaker 1: with astronomy, with a certain imagination. Uh, nothing wrong with imagination,
Speaker 1: but you should remember the difference between imagination and good theory. Yeah.
Speaker 1: So for starters, he believed Earth's moon was habitable, which
Speaker 1: is not a crazy thing to to think. There are
Speaker 1: people today who think that that, yes, given appropriate technology,
Speaker 1: we could live on the moon. And and it certainly
Speaker 1: wasn't all that unusual back then a lot of people
Speaker 1: thought stuff like this. But what's more, he also identified
Speaker 1: what he took to be structures on the moon. He
Speaker 1: thought he observed a vast city. And even when it
Speaker 1: had called it Volver, wasn't that a craft ferk album?
Speaker 1: It could be. It could also be a great name
Speaker 1: for a metal bands. There you go, We've already had
Speaker 1: another possible suggestion there. So again he's he's he's not
Speaker 1: a nobody. He's making this this uh, this this claim.
Speaker 1: So if he says there are cities on the moon,
Speaker 1: even one called Velver, people people take the sea, they took,
Speaker 1: they took notice that there's a certain amount of sensation ensued. Uh,
Speaker 1: I mean cities on the moon. Right, So the notion
Speaker 1: resonated through the media of the day, through the culture
Speaker 1: of the day, influencing the literary world, and and not
Speaker 1: just early sci fi. It laid the seeds for the
Speaker 1: nineteenth and twentieth century telescope sightings of canals on Mars,
Speaker 1: which will discuss more in a bit, which you know
Speaker 1: greatly influenced our perception of the red planet and continues
Speaker 1: to sort of color our our perception and expectations of
Speaker 1: the planet Mars. Yeah. It also, uh again, influenced literature.
Speaker 1: Alfred Lord Tennyson wrote of of these lunar cities in
Speaker 1: his poem tim Buck two. He wrote, I saw the
Speaker 1: smallest grain that dappled the dark Earth, the indistinctist atom
Speaker 1: in deep air, the Moon's white cities, and the opal
Speaker 1: width of her small glowing lakes, her silver heights unvisited
Speaker 1: with dew of vagrant cloud, and the unsounded, undescended depth
Speaker 1: of her black hollows. That's good stuff, man. Yeah. Tennyson
Speaker 1: is not usually one of my favorite poets, but I
Speaker 1: like that. Well, yeah, you you inject a little sci
Speaker 1: fi and uh it's a it's a whole different kettle
Speaker 1: of fish, right. I should also point out the growth
Speaker 1: thousand Uh you know, it wasn't all just cities on
Speaker 1: the Moon. Uh In terms of his astronomical contributions, he
Speaker 1: also suggested that lunar craters were caused by meteorite strikes,
Speaker 1: which is reasonable, right, uh So, but we should get
Speaker 1: to his explanation for the ashen light, which is fantastic.
Speaker 1: So this is quoted and discussed in the book Atlas
Speaker 1: of Venus by Peter Cattermole and Patrick Moore from Cambridge
Speaker 1: University Press. And so they're writing about growth thousand. I'm
Speaker 1: sure I'm saying his name wrong, but that that's the
Speaker 1: closest I can do growth thausand his opinions on the
Speaker 1: action light of Venus. And so apparently Growthausand noticed that
Speaker 1: astronomers had claimed to see the light in seventeen fifty
Speaker 1: nine and then again in eighteen o six, which means
Speaker 1: that the main previous sightings in his lifetime were separated
Speaker 1: by forty seven Earth years, which is seventy six Venus years.
Speaker 1: And Growthausand wrote, quote, we can assume that some Venusian
Speaker 1: Alexander or Napoleon then attained universal power if we estimate
Speaker 1: that the ordinary life of an inhabitant of Venus lasts
Speaker 1: a hundred and thirty Venusian years, which amounts to eighty
Speaker 1: Earth years. The reign of an emperor of Venus might
Speaker 1: well last for seventy six Venusian years. The observed appearance
Speaker 1: is evidently the result of a general festival illumination in
Speaker 1: honor of the ascension of a new emperor to the
Speaker 1: throne of the planet. What do you think, Thumbs up?
Speaker 1: Thumbs down. I'm gonna have to give a thumbs down
Speaker 1: to that. Why, I mean, assuming he wasn't just joking around,
Speaker 1: if if he's presenting this is uh, is anything close
Speaker 1: to a possible explanation that it is a bit ridiculous.
Speaker 1: It's there's so many, so many leaps of faith one
Speaker 1: has to take there. I think that's that's a terrible explanation,
Speaker 1: even if you think there's life on the surface of Venus,
Speaker 1: because how would you be timing out the coronation process later. Yeah,
Speaker 1: you're making so many assumptions about about life on Venus. Uh.
Speaker 1: He also later suggested that the ashen light might be
Speaker 1: due to Venutian slash and burn agriculture, in which farmers
Speaker 1: of Venus would burn down these huge stretches of jungle
Speaker 1: in order to clear the land for tilling and planting. Quote,
Speaker 1: large migrations of people would be prevented so that possible
Speaker 1: wars would be avoided by abolishing the reason for them.
Speaker 1: Thus the race would be kept united. Well, I don't
Speaker 1: know that feels a little more reasonable. I mean, really,
Speaker 1: I guess in both cases what he's essentially doing is reasonable.
Speaker 1: He's saying, how would I explain this light on venus?
Speaker 1: And on both cases he's assuming that there is some
Speaker 1: sort of intelligent life form. What do we do on
Speaker 1: our planet? And then how might I model behavior on
Speaker 1: the other side. Yeah, if if the dark side of
Speaker 1: Earth is shining, what causes that? Well, it's probably some
Speaker 1: huge illumination for some festival or its agricultural burning. Right,
Speaker 1: it can't be just the light of cities, because then
Speaker 1: it would be more stationary, wouldn't be this, wouldn't have
Speaker 1: this this frequency to it, right, Uh, And so all
Speaker 1: this stuff it's it sounds cookie to us, but it's
Speaker 1: not in principle as cookie as it sounds. Because Robert,
Speaker 1: as you mentioned a minute ago, lots of people used
Speaker 1: to believe that there were visible civilizations on the surfaces
Speaker 1: of other rocky planets in the Solar System. We've talked
Speaker 1: before about the American author and astronomer Percival Lowell. You know,
Speaker 1: he comes to mind who Around the turn of the
Speaker 1: twentieth century he was writing about the supposed canals of Mars,
Speaker 1: which we talked about. I thought that the canals of
Speaker 1: Mars were evidence of the handiwork of Martian civilization. Now,
Speaker 1: of course, later it was discovered that the observations that
Speaker 1: people thought were canals on the surface of Mars were illusions,
Speaker 1: and Mars does not have canals. Yeah, they were actually
Speaker 1: first observed in eighteen seventy seven and then confirmed, uh
Speaker 1: if you will, by various dedicated astronomers around the world.
Speaker 1: So this is something that Carl Sagan actually wrote a
Speaker 1: little bit about in The Demon Haunted World, his his
Speaker 1: book that essentially about science communication and the struggle between uh,
Speaker 1: you know, scientific literacy and uh uh and our susceptibility
Speaker 1: to everything from conspiracy theory to pseudoscience. He wrote A
Speaker 1: network of single and double straight lines was reported criss
Speaker 1: crossing the Martian surface, and with such uncanny geometrical regularity
Speaker 1: that they could only be of intelligent origin. Evocative conclusions
Speaker 1: were drawn about a parched and dying planet populated by
Speaker 1: an older and wiser technical civilization dedicated to conservation of
Speaker 1: water resources. So hundreds of canals were actually mapped and
Speaker 1: named um. But but just as with the action light,
Speaker 1: there were no photos. This was all based on observation
Speaker 1: through telescopes. Most astronomers did not see them, but some did,
Speaker 1: and says Sagan suggests that, you know, it might have
Speaker 1: even been more of a you know, perceptual delusion. But
Speaker 1: but one of the key differences here is that canals
Speaker 1: on Mars, that's something that you can keep looking for.
Speaker 1: Unless you're rolling out some elaborate explanation about canals disappearing
Speaker 1: or being hidden by secretive Martians, They're going to remain
Speaker 1: there and you can look for them. Yeah, it should
Speaker 1: be a fixed feature of the surface. Right, So as
Speaker 1: our observation abilities improved, we found that they did not exist.
Speaker 1: When Marin or nine orbited the planet in nine UM
Speaker 1: and Sagan was an experiment er for that mission, he said,
Speaker 1: there were, of course no canals at all, and nobody
Speaker 1: was surprised by this by that point. But but again,
Speaker 1: this was a perfectly testable situation in the science corrected
Speaker 1: our expectations and understanding of the surface of Mars. And
Speaker 1: now we understand, as we've discussed in the past, we
Speaker 1: understand more about the surface of Mars than we do
Speaker 1: about the the bottom of earth oceans. Yeah, uh yeah,
Speaker 1: And so that's a fortunate situation where this misconception could
Speaker 1: be cleared up. Like you say, but as you implied,
Speaker 1: the problem with the light on Venus is that it
Speaker 1: is observed to be infrequent and difficult to detect, very faint,
Speaker 1: and it's not always there. So this makes it harder
Speaker 1: to verify or disconfirm through experimentation. Right now, as far
Speaker 1: as as the idea of life on Venus, we actually
Speaker 1: just did a recent episode on the possible existence of
Speaker 1: life on Venus. But of course, as we know, if
Speaker 1: it were to exist, it would not take the form
Speaker 1: of a surface dwelling agricultural civilization. The surface of Venus
Speaker 1: has an average temperature of over four hundred and fifty
Speaker 1: degrees celsius or over eight hundred and fifty degrees fahrenheit.
Speaker 1: Then that makes complex life totty much impossible. If if
Speaker 1: life were to exist on Venus, astrobiologists generally think that
Speaker 1: it would consist of micro organisms living dispersed in vapor
Speaker 1: droplets in the clouds of the upper Venusian atmosphere, higher
Speaker 1: up where it's cooler. So I guess we should get
Speaker 1: back to the question of the action light. It is
Speaker 1: the action light like the canals of Mars. Is it
Speaker 1: just an observer illusion? And if not, what is the
Speaker 1: real cause? What could really make the nighttime side of
Speaker 1: Venus glow? All right, We're gonna take a quick break
Speaker 1: and then when we come back we will continue. Thank you,
Speaker 1: thank you. All right, we're back. So I think it's
Speaker 1: time to turn to a paper by William Sheehan, Klaus brosch,
Speaker 1: Dale Crookshank, and Richard Baum from the Journal of the
Speaker 1: British Astronomical Association, and the papers called the Ashen Light
Speaker 1: of Venus the oldest unsolved solar system Mystery, and this
Speaker 1: paper tried to take a look at the action light
Speaker 1: to determine if it's real, and if it is real,
Speaker 1: what could explain it. So they point out that many
Speaker 1: of the observations of the action light are very likely illusory,
Speaker 1: based on optical illusions or inadequate equipment, poor telescopes, all
Speaker 1: that stuff. But really the question is not are some
Speaker 1: of the observations of the action light illusory obviously some
Speaker 1: of them are, but are all of them illusory? Or
Speaker 1: is there there's something real to it? And there's a problem.
Speaker 1: The identify in the term action light apparently appears to
Speaker 1: refer to at least three different kinds of observation scenarios.
Speaker 1: So one of them is you've got the dark side
Speaker 1: of Venus and it appears paler or the same brightness
Speaker 1: but a different color or darker against a bright twilight
Speaker 1: or daylight background. And then another type of observation is
Speaker 1: the planet is observed near inferior conjunction. Remember that's when Venus,
Speaker 1: Earth and the Sun line up, with Venus and Earth
Speaker 1: on the same side of the sun, so we're near that,
Speaker 1: and they see the planet against a bright sky or
Speaker 1: in daylight, and the extent shin of the horns of
Speaker 1: the crescent planet seemed to go all the way around
Speaker 1: the planet and form a bright ring, and they say
Speaker 1: this is probably due to scattering of sunlight from the
Speaker 1: planet's atmosphere. And then third, finally there's the true ashen light,
Speaker 1: in which the dark side of the planet appears as
Speaker 1: a brighter glow against a darker background sky, and it's
Speaker 1: that third category we're going to be most interested in here, right,
Speaker 1: because that is that is the true action light. Yes,
Speaker 1: though all three categories are met by various observations around
Speaker 1: the years, so so they take a look at all
Speaker 1: of them, but that the third one is considered the
Speaker 1: true ash and light. And given the different uses for
Speaker 1: the term, obviously it can be hard to nail down
Speaker 1: an explanation that fits them all perfectly. I mean this
Speaker 1: goes back to our Will of the Wisp episode. Like
Speaker 1: if you're trying to say, Okay, if people really did
Speaker 1: see something, what's the best material explanation for it? You've
Speaker 1: got a problem in that the sightings are so different
Speaker 1: in the way they're described. Yeah, they range from the
Speaker 1: original ashtion lie to these descriptions of something that's more
Speaker 1: rusty and uh and sort of like the color of
Speaker 1: dried blood. But there have been plenty of explanations proposed
Speaker 1: over the years. So for example, how about the idea
Speaker 1: of earth shine, Like is light reflecting off of Earth
Speaker 1: and then bouncing to Venus so that we can occasionally
Speaker 1: occasionally see the light bouncing off of Earth reflected from
Speaker 1: the surface of Venus at night. Uh, The authors say no.
Speaker 1: Many calculations have been done and found earth shine to
Speaker 1: be much much too weak to explain the observations, but
Speaker 1: people have tried to reason this way. One explanation along
Speaker 1: these lines was offered by a guy named god Free Sykes,
Speaker 1: who apparently worked for Personal Lowell, uh you know Personal
Speaker 1: Lowell of the Canals of Mars fame and god Free
Speaker 1: Sykes thought that Venus was tidally locked with the Sun,
Speaker 1: which would mean that one the same side of it
Speaker 1: was always facing inward towards the Sun, and that it's
Speaker 1: dark side, which always faced away from the Sun, would
Speaker 1: be completely covered in a hemisphere year of ice. And
Speaker 1: this ice, being highly reflective, would reflect light from the
Speaker 1: Earth and other planets and stars and all all that
Speaker 1: all that light coming into the dark side of Venus
Speaker 1: would reflect off of the ice, the ice sheet on
Speaker 1: that side of the planet back out into space, and
Speaker 1: thus we would see that kind of shine. Obviously this
Speaker 1: is wrong for you know, clear reasons, because we now
Speaker 1: know that Venus is too hot for liquid water, let
Speaker 1: alone ice. Alright, what else do we have? People have
Speaker 1: proposed lightning? How about lightning? Well, that makes sense, So
Speaker 1: we have lightning in our world, and it certainly can
Speaker 1: light up the sky. Yeah, there's actually long been a
Speaker 1: question of whether there's lightning in the clouds of Venus
Speaker 1: and if so, how much. And there does appear to
Speaker 1: be some evidence for lightning on Venus, including these what
Speaker 1: are called low frequency quote whistler waves that are detected
Speaker 1: in the Venusian atmosphere, like for example, they were detected
Speaker 1: by the Venus Express vehicle. But astronomers have also largely
Speaker 1: ruled out the lightning explanation because the lightning would just
Speaker 1: be too faint to be seen on Earth. So the
Speaker 1: authors of this paper right quote, the auroral and lightning
Speaker 1: theories have both been eliminated because though visible spectrum night
Speaker 1: side air glow on Venus was discovered by the veneera
Speaker 1: nine intent spacecraft, and lightning has also been confirmed from
Speaker 1: spacecraft observations, the illumination they produce is orders of magnitude
Speaker 1: too faint to be detectable with the eye from Earth.
Speaker 1: So it's not just a little bit too faint, it
Speaker 1: would be way too faint. And it likewise that means
Speaker 1: that whatever is occurring, if it's occurring, is uh is
Speaker 1: substantial enough that it is it is orders of magnitude
Speaker 1: beyond what near lightning activity or rural activity would consist
Speaker 1: of right for us to be seeing it with the
Speaker 1: eye and telescopes from Earth. Now, you've got a couple
Speaker 1: of remaining hypotheses. One of them is infrared thermal emission
Speaker 1: from the night side. We know that the surface and
Speaker 1: lower atmosphere of Venus are red hot, and she had
Speaker 1: at all right quote. Since the absorption and light scattering
Speaker 1: by sulfuric acid aerosols in venous atmosphere are weak at
Speaker 1: visible and near infrared wavelengths, a number of authors have
Speaker 1: proposed that at least in principle, the lower atmosphere from
Speaker 1: fifty kilometers down to the surface might produce a glow
Speaker 1: that for a suitably dark adapted observer under the right
Speaker 1: atmospheric conditions both on Venus and the Earth, may be
Speaker 1: dimly perceived at visual wavelengths. So maybe the planet is
Speaker 1: so hot it's glowing in a way that the atmosphere
Speaker 1: does not appropriately scatter the light, and the light comes
Speaker 1: through to us. And in their article Able and Lawrence
Speaker 1: right about this idea, uh they write that apparently the
Speaker 1: thick atmosphere occasionally thins in places, allowing the hot surface
Speaker 1: to be seen. Quote. The problem is that this would
Speaker 1: only be visible in the infrared part of the spectrum,
Speaker 1: well beyond the threshold of the human eye, So infrared
Speaker 1: heat is below the frequency of the visual band of
Speaker 1: the the electromagnetic spectra. And she Han and co authors
Speaker 1: right quote. Thermal emission of a body at venus temperature
Speaker 1: reaches its peak value at about three point nine five
Speaker 1: micrometers wavelength, which is invisible to the eye, and decreases
Speaker 1: very rapidly towards shorter wavelengths that the eye can detect.
Speaker 1: The longest wavelength visible to the human eyes about zero
Speaker 1: point seven micrometers. Using Planks law, we calculate that wind
Speaker 1: venus is very near inferior conjunction when it just a
Speaker 1: few degrees of separation from the sun. The intensity of
Speaker 1: the heat emission at zero point seven micrometers is some
Speaker 1: thirty thousand times weaker than the brightness of the sunlit sky,
Speaker 1: So the lowest possible frequency of light that could feasibly
Speaker 1: be seen by the human eye, that the lowest frequency
Speaker 1: that's visible to us is produced at far too weak
Speaker 1: an intensity. On an object of the temperature of venus,
Speaker 1: compared to the sky around it. So, yes, Venus is
Speaker 1: very hot, but not hot enough to glow in a
Speaker 1: way that we could see from Earth with the naked
Speaker 1: eye through a telescope lens. Alright, so it has to
Speaker 1: be something else, right, Yeah, So it can't be the
Speaker 1: planet glowing from heat. So what's left pretty much just
Speaker 1: one hypothesis, and that's the hypothesis of oxygen emission. So
Speaker 1: in nineteen sixty seven, the Mirrorner five spacecraft did an
Speaker 1: early fly by Venus and detected what was believed to
Speaker 1: be an ultra violet quote night air glow on the
Speaker 1: dark lamb of the planet. So there was a nighttime
Speaker 1: on the night side of the planet. The atmosphere was
Speaker 1: glowing slightly and scientists at the time thought that this
Speaker 1: night glow on the dark side of the Venus might
Speaker 1: be due to chemical reactions in the atmosphere or possibly
Speaker 1: due to the atmosphere being bombarded by charged particles from
Speaker 1: the Sun. And then later the Mirrorner ten vehicle did
Speaker 1: another Venus fly by in nineteen seventy four and it
Speaker 1: also found both a daytime and nighttime air glow around Venus,
Speaker 1: and it was found to be ten times brighter than
Speaker 1: had been predicted. So this sounds really promising, right, Yeah,
Speaker 1: and this is this is a perfectly reasonable scientific explanation
Speaker 1: for what could be occurring. Yeah, exactly. So at the
Speaker 1: time people thought that the problem of the ashen light
Speaker 1: maybe was solved. So one version of the chemistry explanation
Speaker 1: from oxygen emission goes like this, You've got UV radiation
Speaker 1: from the Sun also ions charge particles flying out from
Speaker 1: the Sun, and this UV radiation and other stuff hits
Speaker 1: particles in the upper atmosphere of Venus. And the atmosphere
Speaker 1: of Venus is made made up mostly of carbon dioxide,
Speaker 1: which contains one carbon atom and two oxygen atoms. And
Speaker 1: when the solar bombardment hits these carbon dioxide molecules, it
Speaker 1: splits them into and what it leaves in their wake
Speaker 1: when when they get split up is you get a
Speaker 1: carbon monoxide molecule which has one oxygen atom one carbon atom,
Speaker 1: and then you get a single isolated oxygen atom. And
Speaker 1: single isolated oxygen atoms are not happy. They're lonely, they
Speaker 1: don't want to be out on their own, and they
Speaker 1: tend to recombine into other molecules. In this case, combining
Speaker 1: with other free oxygen atoms to orm O two, two
Speaker 1: oxygen atoms together in a molecule, and when this combination happens,
Speaker 1: the atoms emit photons of light in the visible spectrum,
Speaker 1: and it's often described as a green light. And apparently
Speaker 1: this has been observed with instruments like apparently the Keeck
Speaker 1: one telescope in Hawaii has previously spotted green light in
Speaker 1: the atmosphere of Venus, which is consistent with the light
Speaker 1: that would be emitted by free oxygen atoms combining to
Speaker 1: form O two in the in the Venusian atmosphere. And
Speaker 1: that light was apparently also observed by the Soviet spacecraft
Speaker 1: Vanera nine and Vanera tin. And what's more, this theory
Speaker 1: could help explain why there are some years when so
Speaker 1: many observers claim to see the light and other years
Speaker 1: in which nobody can find it, because this would depend
Speaker 1: on the atmosphere of Venus being bombarded by the Sun.
Speaker 1: So variations in solar activity could explain variations in the
Speaker 1: emissions due to atmospheric chemistry on Venus, like when the
Speaker 1: Sun is hitting the planet hardest, the oxygen mission becomes
Speaker 1: the strongest, well it sounds like a pretty strong theory. Yeah,
Speaker 1: it does. It's so far at least so, but is
Speaker 1: it is it accepted? Is this is anywhere you're accepted?
Speaker 1: Unfortunately not. The authors conclude that while this this theory
Speaker 1: probably has the best chance of being correct, ultimately they
Speaker 1: decided probably is not the correct explanation. So they decided
Speaker 1: to investigate the validity of the oxygen emission hypothesis in
Speaker 1: the spring of two thousand twelve, and they used visual
Speaker 1: observation and cc D or charge couple device recorded imagery
Speaker 1: of with different telescopes and different filters and observing visually.
Speaker 1: There were occasions where they thought maybe they saw the
Speaker 1: ashen light when they looked at Venus in two thousand twelve.
Speaker 1: The authors actually quote Johann Shredder saying it had the
Speaker 1: texture of thought, Oh well, that's that's a that sounds
Speaker 1: a lot like I'm making it up. Yeah, well no,
Speaker 1: I mean I think that's what they're saying. It's like
Speaker 1: they're sitting there looking at it and they think maybe
Speaker 1: they can see it, but they get the sensation that
Speaker 1: maybe they're seeing with with their minds as much as
Speaker 1: seeing with their eye. This is this is staring at
Speaker 1: the magic eye image. This is staring into the woods
Speaker 1: and trying to convince yourself you see something. Yeah. But
Speaker 1: of course the authors here aren't aren't just trying to
Speaker 1: go by their own perceptions. They want to use neutral
Speaker 1: imagery to see if they can capture this somehow. So
Speaker 1: they used a special filter for green light, and with
Speaker 1: that special filter they were able to detect a glow
Speaker 1: that could be imaged. I've actually got an image here
Speaker 1: with a very creepy looking crescent and and some green light.
Speaker 1: I don't know if you can see that, Robert, it's
Speaker 1: yeah on here. Yeah, that that that is. That is
Speaker 1: creepy looking. But the authors also used some planet simulation
Speaker 1: comparisons to establish that the red and green ashen light
Speaker 1: perceptions that they thought they saw and that were imaged,
Speaker 1: we're probably due two scattered light from the illuminated to
Speaker 1: the unilluminated side, and there was no actual ashen light detected.
Speaker 1: Another big problem I'm thinking about here. Most of the
Speaker 1: astronomers who have reported seeing the ash and light over
Speaker 1: the past three centuries have not had this kind of equipment,
Speaker 1: you know, with with the equipment available in the past,
Speaker 1: it seems highly possible that observers would not likely have
Speaker 1: been able to see this emission for moto formation. So
Speaker 1: it's not that there is no light coming off of
Speaker 1: venus from from the chemistry of the atmosphere, that it
Speaker 1: does appear to be coming off of venus. The question
Speaker 1: is would it have ever been bright enough for people
Speaker 1: with telescopes hundreds of years ago to see And the
Speaker 1: answer looks like probably not. It's kind of like staring
Speaker 1: across a great lake, right, and maybe you can distantly
Speaker 1: see the distantly see the other side. And then if
Speaker 1: you if you're trying to figure out if you can
Speaker 1: see people or not, you know, and then if you
Speaker 1: if you investigate, you can later find out, oh, yeah,
Speaker 1: there are people on the other side, but it's it's
Speaker 1: a far different thing than being able to actually see
Speaker 1: them from your shore. Yeah. So ultimately the authors conclude
Speaker 1: that they don't know for sure. The most sensible explanation
Speaker 1: at this point is, unfortunately, the illusion hypothesis that despite
Speaker 1: the many reports over the years by by very respected astronomers,
Speaker 1: the phenomenon is most likely due to observer error and
Speaker 1: sort of optical artifacts from imperfect telescopes. And there's an
Speaker 1: example they give and in their paper. In the early es,
Speaker 1: there's a there was a German astronomy writer named Daniel
Speaker 1: Fisher who produced an example of what he thought at
Speaker 1: the time was a directly captured digital image of the
Speaker 1: action light with a charge coupled device, you know, like
Speaker 1: a digital camera. Unfortunately, it now seems clear that the
Speaker 1: image is actually just a case of what's known as
Speaker 1: filter leakage, and Fisher himself has accepted the fact that
Speaker 1: the image is is not a real image of the
Speaker 1: action light and has actually come to strongly doubt the
Speaker 1: existence of the action light. So the reasons he gives
Speaker 1: are there are no good direct images of it captured
Speaker 1: by a neutral device. And then he he says, quote
Speaker 1: just as amateur planetary imagers have started getting really good
Speaker 1: reports have dwindled. This is what we talked about earlier.
Speaker 1: It's kind of like, you notice how as soon as
Speaker 1: cell phone cameras are everywhere, suddenly bigfoot sightings and UFO
Speaker 1: sightings drastically drop off. It seems like, just as people
Speaker 1: should be really having the ability to capture this image
Speaker 1: but on a neutral recording device, suddenly people aren't seeing
Speaker 1: it nearly as much as they used to uh, and
Speaker 1: so Fisher actually now thinks that the phenomenon is fringe
Speaker 1: science and calls it quote the locknest monster of astronomy. Now,
Speaker 1: I don't think it's that bad because it's it's not
Speaker 1: a monster. There's no reason that you you shouldn't expect
Speaker 1: to find some kind of strange, chemically produced light on
Speaker 1: the dark side of a planet, right, that's perfectly plausible.
Speaker 1: The question is just we're people really seeing it or
Speaker 1: was it all tricks of the eye and tricks of
Speaker 1: the mind. And certainly the more it became a mystery
Speaker 1: to write it has this appeal, Like you the near
Speaker 1: fact that we're talking about it is is evidence of this,
Speaker 1: you know, and the action light of Venus. Who who
Speaker 1: doesn't want that to be real? Who doesn't want to
Speaker 1: to glimpse that and partake of the mystery as well? Yeah?
Speaker 1: Exactly so. Ultimately, the authors of the paper conclude quote
Speaker 1: none of the putative images of the actual action light
Speaker 1: can be regarded as convincing. They appear to be due
Speaker 1: to filter leakage, crescent glare, and excessive image processing used
Speaker 1: to bring out dark side detail. And yet despite their doubts,
Speaker 1: they say it's still possible that the action light does
Speaker 1: exist despite their inability to detect it. One possible explanation
Speaker 1: could be that maybe it's only during extraordinary solar events,
Speaker 1: such as like coronal mass ejections, because that would provide
Speaker 1: extra bombardment of the planet Venus enough that its atmosphere
Speaker 1: really has a lot of oxygen emission going on, and
Speaker 1: that oxygen emission spectrum can be seen from Earth only
Speaker 1: during those times when the planet is hit with really
Speaker 1: strong solar radiation. Well, that that makes sense, and it's
Speaker 1: in as in a sense, it would be the echo
Speaker 1: of a may your solar anomaly. Yeah, exactly. They don't
Speaker 1: mention whether what because we know about we know about
Speaker 1: solar activity in the past, so they don't mention trying
Speaker 1: to line up observations of it in the past with
Speaker 1: what the Sun was doing at the time. I wonder
Speaker 1: if somebody tried to do a correlation analysis there if
Speaker 1: they would find anything that seems like the logical next step,
Speaker 1: doesn't it, But they right at the end quote for
Speaker 1: the time being, we can say no more. The action
Speaker 1: light cannot yet be laid to rest, though inevitably it
Speaker 1: becomes a little harder to believe in. With each passing elongation,
Speaker 1: it might finally transpire that the longest standing mystery and
Speaker 1: Solar System astronomy is nothing more than a stubborn illusion.
Speaker 1: But in the meantime, the observer who enjoys a challenge
Speaker 1: is encouraged to remain on the key viv or on
Speaker 1: the alert. So here's my By the way, I had
Speaker 1: a crazy idea float here's my crazy question linking our
Speaker 1: two venous episodes. So, first of all, I do want
Speaker 1: to say I accept their their conclusion that by far
Speaker 1: the most reasonable explanation of the point seems to be
Speaker 1: observer error. But if it is real, what if there
Speaker 1: is microbial life in the clouds of Venus, And if
Speaker 1: there is, what if it's bioluminescent. How do you like that? Yeah?
Speaker 1: So like if the ashen light is real and it's
Speaker 1: the glowing equivalent of periodic algal blooms and the clouds
Speaker 1: on the hot house planet, So uh yeah, I wonder
Speaker 1: about that. Astrobiologists, astronomers, planetary scientists tell me why this
Speaker 1: is wrong? Well, I mean, the the one idea that
Speaker 1: comes to mind here is that it would have to
Speaker 1: be pretty intense during these flare apps. They would have
Speaker 1: to be again an order of orders of magnitude above
Speaker 1: what mere lightning or a rural activity would consist of. Correct,
Speaker 1: And it's I mean it's difficult to I mean, we've
Speaker 1: all seen terrific lightning storms. We've seen uh, you know,
Speaker 1: the Aurora borealis at least in you know, images of it,
Speaker 1: and it's uh, it's it's on inspiring and also challenging
Speaker 1: to imagine some sort of biological phenomena occurring of the
Speaker 1: same caliber, you know. But but then again, I mean
Speaker 1: it's a long shot, but maybe yeah, somebody at least
Speaker 1: if you if you know what kind of spectra that
Speaker 1: a big luminescent organism in a cloud could produce, Uh,
Speaker 1: do the math? What does that? Is it possible? I
Speaker 1: mean it kind of matches up really with the ideas
Speaker 1: of like coronations and wars and slash and burn agriculture,
Speaker 1: because what are these but um, but the infrequent bursts
Speaker 1: of activity that line up with biological activity on our planet.
Speaker 1: So this could be, yeah, the case of an intense
Speaker 1: season of mating or even some sort of essentially a war.
Speaker 1: You know, I'm thinking about the way that that different
Speaker 1: varieties of coral wage wars against each other for dominance,
Speaker 1: and it's just um the and the you know, the
Speaker 1: death that takes place at the borders between the two. Uh.
Speaker 1: Maybe the action light is that sort of phenomenon, the
Speaker 1: you know, two different rival species of bioluminescent organisms clashing,
Speaker 1: you know, micro microbial war in the venus and clouds.
Speaker 1: That's a good that's a good story. I like that one. Well,
Speaker 1: here's another thing I want to know. Do we have
Speaker 1: any astronomers out there among you all in the audience
Speaker 1: who have seen the action Light? Do you think you've
Speaker 1: seen it? If you've seen it, Uh, do you think
Speaker 1: it's likely you could have been mistaken or there are
Speaker 1: reasons you have for thinking you were not mistaken? We
Speaker 1: would like to hear about this. Yeah, anybody else who
Speaker 1: has any stories about attempting to see something and that
Speaker 1: that curious mindset that we're talking about, where you're you're
Speaker 1: sort of screening to see something you don't see or
Speaker 1: hear something you can't hear, and what it's like to
Speaker 1: sort of creep your way up towards that line. Yeah,
Speaker 1: it's always shocking what our brands are capable of can't
Speaker 1: trust them. You can't, you can't. But it's all we have.
Speaker 1: I mean, it's not all we have. We have science.
Speaker 1: That's the one of the the key r D mints
Speaker 1: here is that we do have scientific inquiry. We have uh,
Speaker 1: the ability to observe and record data. That should be it.
Speaker 1: That's a great pro science slogan. Science better than your brain,
Speaker 1: that's right, I mean created by our brain. But uh,
Speaker 1: but but so much better at tackling problems like this. Agreed. Well, uh,
Speaker 1: I think that does it for today. But this has
Speaker 1: been fun, Robert, Yeah. Yeah. Perhaps we'll return to Venus
Speaker 1: in the future. For the time being, head on over
Speaker 1: to stuff to Blow your Mind dot com. That's where
Speaker 1: we'll find all the episodes of the podcast, including those
Speaker 1: past episodes on Venus, including that Will of the Whisp episode,
Speaker 1: and social media links. If you want to find out
Speaker 1: what we're doing on Facebook, Twitter, Tumblo, you want to
Speaker 1: see if we have some sort of revide live tour
Speaker 1: in the works, there will be a tab up there
Speaker 1: for that. Huge thank you as always to our excellent
Speaker 1: audio producers Alex Williams and Tarry Harrison. If you would
Speaker 1: like to get in touch with us directly, to let
Speaker 1: us know feedback on this episode during the other to
Speaker 1: let us know if you've seen the ashen light or
Speaker 1: looked forward and not seen it. To let us know
Speaker 1: uh topic you think maybe we should cover in the future,
Speaker 1: or just to say hi, let us know where you
Speaker 1: listen from, tell us who you are. You can email
Speaker 1: us at blow the Mind at how stuff works dot
Speaker 1: com for more on this and thousands of other topics.
Speaker 1: Does it how stuff works dot com. B