TRANSCRIPT: The Great Meteor Procession of 1913

On February 9, 1913 an extraordinary and unique phenomenon was observed by multiple witnesses across Canada, the US and the island of Bermuda. Known as the Great Meteor Procession, this event seems to suggest that Earth once had, at least for a time, a second, small natural satellite. Think about that, that would mean that up until 1913 Earth technically had two natural moons.

Over a hundred reports exist of this phenomenon and what they indicate is that between 40 and 60 very slow moving fireballs arranged in groups moving in what appeared to be an identical path crossed the sky over the course of several minutes. This would be unusual for a normal meteorite, those tend to be lone wolves. It would be less unusual for a meteor shower, though those tend to involve dust grains and the apparent size of these fireballs would be more consistent with sizeable meteorites.

Meteor showers also tend to be fairly predictable events. They happen at the same time each year as earth passes through debris field left in the trail of comets that have crossed our orbit at some point in the past. Meteor showers also exhibit something called a radiant, this is a point in the sky where meteors, if you trace them backwards, appear to originate.

Astronomer Clarence Chant determined from the reports that The Great Meteor Procession did not have a radiant, and instead seems to have followed a great circle trajectory. There are thought to be two possible reasons for this. The parent object might have encountered earth before, grazed the atmosphere at a shallow angle and skipped back out into space. This is not unheard of, a rather large fireball was witnessed doing just that over western North America in 1972. Once back in space it might have broken up into pieces setting up for the multiple fire balls observed when it encountered earth again and was drawn in.

The second possibility is that whatever was the source for the meteors was formerly in orbit of earth. Now, bodies in the solar system, including earth, can capture other objects such as asteroids. Quite a few of the smaller moons in the outer solar system are believed to be just that, captured asteroids. They can eventually end up in stable orbits if the conditions are right, or they can orbit for a time in a decaying orbit. The latter may have been what happened here.

But there's another possibility and while it's sort of one of those old, dusty theories within space science that not a lot of people remember it was at least intriguing at the time. Astronomer John O'Keefe proposed that instead the material that made up the fireballs was instead a remnant of a ring system Earth might have had at one time, similar to Saturn.

This ring system would have been produced by the action of lunar volcanos long ago when they were still active, which relates to another theory of O'Keefe's that tektites, a group of natural glasses that show clear evidence of once having flown aerodynamically through the atmosphere, originated on the moon. His main evidence for this was a curious lack of water in tektites, internally they are very dry for something that originated on earth.

The theory was given serious consideration by science at one time. However subsequent studies of tektites have shown that they are most likely generated from earth rock melted during crater-forming asteroid impacts. The evidence for this has accumulated and is now pretty convincing but it doesn't really answer O'Keefe's ring theory.

Might the moon early in its history have sprayed materials far enough out into space to form a planetary ring system around earth? There really isn't much evidence for it unfortunately, other than potentially the Great Meteor Procession. And with that, no associated meteorites were ever found so we may never know the origins of this event. But it's at least fun to imagine planet earth with a second tiny moon, or even a ring long ago in the past. 

Thanks for listening! I am futurist and science fiction author John Michael Godier currently plugging my second channel. It's dedicated to science fiction and the science behind it and in a not-so-creative frenzy one night I named it John Michael Godier II, link in the description below and be sure to check out my books at your favorite online book retailer and subscribe to my channel for regular, in-depth explorations into the interesting, weird and unknown aspects of this amazing universe in which we live. 

TRANSCRIPT: Detecting Alien Stellar Engines

The universe can be a chaotic place where galaxies collide and stars get ejected to wander the intergalactic universe unassociated with their parent galaxy. If this situation were to happen to an inhabited star system, it might not be desirable to be ejected, or likewise if alien astronomers calculated a high likelihood that their star might be eaten by a black hole in a few million years, they might choose to construct a monumental, but hypothetically possible, megastructure that can actually move their star.

Moving a star requires a variant of the Dyson shell concept called a Shkadov drive, or class A stellar engine. It's a surprisingly straightforward idea originally put forth in 1987 by Dr. Leonid Shkadov. The idea is to build an enormous spherical mirror to reflect the radiation pressure of a star in a different direction. This would have the effect of creating thrust and would propel the star in whatever direction the alien race wished it to go. As the star moved, it would carry its planets with it just as the sun does now with our planets as it travels through the galaxy.

The problem with this idea is that the thrust would be very slight and moving a sun-like star any large distance would take millions of years so it's difficult to envision that too many of these things get built out there in the universe. But it is possible, and there is room for other scenarios where a civilization might build such a thing to move a star just a small distance if that's what they happened to need. Or, if you have a civilization that's billions of years old and very forward thinking, they might not blink an eye at projects that take millions of years to complete.

So the question is, if there are civilizations building Shkadov drives, would we be able to detect them? Just such a method was put forth in a paper, link in the description below, by Dr. Duncan Forgan of the University of Edinburgh in 2013. It's worth noting that one of the main ways we detect exoplanets is by looking at the light curves of their stars as they pass in front of it and block light.

In other words, the data needed to detect a Shkadov drive is being taken anyway in the course of finding exoplanets and studying stars. It's more a matter of someone noticing something odd in those light curves, which is how Boyajian's star was identified. Now there are issues that Forgan points out, determining if a light curve indeed indicates the presence of a Shkadov drive could be complicated by other things in the light curve, such as the presence sun spots, so much observation would be needed to confirm such a thing.

Forgan also points out that while the chances of finding a star with a Shkadov thruster are exceedingly low but with all the data that's available scientists looking for other things should be aware of strange signatures in light curves that could indicate the presence of a Shkadov drive and anyone wishing to specifically look for them could do so at low cost from already available data.

So add one more way that we might detect an alien civilization independently of radio astronomy. I think this is one of the more unlikely scenarios, I can't imagine this type of megastructure would be very common, but astronomers see all sorts of interesting things in light curves so some day in the future who knows?

Thanks for listening! I am futurist and science fiction author John Michael Godier and if you'd like to help support the channel check out my Patreon page, link in the description below, or check out my books at your favorite online book retailer and subscribe to my channel for regular, in-depth explorations into the interesting, weird and unknown aspects of this amazing universe in which we live.

TRANSCRIPT: The Zoo Hypothesis

The human race has looked out into the night sky for decades with our radio telescopes hoping to find signs of life. And while that search is ongoing, we have yet to see anything. For all intents and purposes, our universe appears quiet and uninhabited by other technologically advanced civilizations.

This could change at any moment, all we need to do is discover evidence of one other sentient species to answer many of our questions about life in the universe, but until that happens we must entertain other possibilities to explain this apparent lack of intelligent life.

One of the possibilities that we face is that intelligent alien races do not advertise themselves, and indeed may hide their existence from us. Known as the zoo hypothesis, it is one of the plethora of hypotheses that offer answers to the Fermi Paradox. It also happens to be among the spookiest.

The Fermi Paradox, formulated by physicists Enrico Fermi and Michael Hart, is very simple. There are billions of stable stars in our universe, and many of them are far older than our own. There is also a high probability that some of these stars host earth-like planets, a notion that has only been strengthened in recent years by the discovery of numerous exoplanets. Likewise, many of those are going to be far older than earth.

Some of those planets would, presumably, develop life like ours that eventually achieves intelligence. Here I have a sticking point, in my opinion I think that ultimately we may well find that microbial life is common in the universe, complex life like our plants and animals scarce, and intelligent life very rare. But I digress. Assuming that civilizations are relatively common then some of those will develop interstellar travel.

Here I have another sticking point. I'm not sure that an advanced civilization would care about interstellar travel. This relates to Simulation Theory, the notion that our universe is a computer simulation of some sort. I cover that theory in my video "Is the Universe real? Or is it a Computer Simulation?" and whether it's actually the case is anyone's guess, though it does appear to be scientifically testable.

But let's say the universe is a computer simulation as a thought experiment. If a civilization concluded that it is a simulation, then they may also conclude that there is no point to messing around with the universe. In such a nihilistic scenario, why not center your society on pleasure and descend into virtual reality utopias that are better than our universe? Think about The Matrix, only as a utopia, though I suppose Agent Smith had a point when he said in the films that they actually did initially try to create a utopia but no one was happy.

But, it's worth noting that we ourselves are striving for interplanetary exploration and eventually interstellar travel. Our behavior is all we can study for now, and that does count for something. Given that habitable planets exist, and they eventually become inhabited and may have done so long before earth did, and those inhabitants eventually spread out into the universe, then the Fermi Paradox notes that the entire galaxy can be explored at sub-light speeds in only a few million years. So why don't we see evidence of alien civilizations everywhere?

This brings us to the Zoo Hypothesis. The idea here is that alien civilizations hide themselves from us, either permanently or will some day reveal themselves and make contact when we've reached a sufficient level of technological and social development.

This may make sense. If the universe is a hostile place full of aggressive species, and your basic nature would be aggressive in some way if you're out boldly exploring the galaxy, then perhaps it's safer to hide and not contact anyone. In this scenario, advanced civilizations simply play it safe and do not interact with one another other than perhaps clandestine interstellar spy missions.

Or a civilization may find value in galactic diversity and not contact anyone so that they may simply study young civilizations and their natural development. This is something we ourselves do, there are still to this day uncontacted stone age tribes on our world and we take care to preserve that both for their own safety and ethical concerns about first contact, which has seldom gone well in the past.

But, you also have to ask a question here. If advanced civilizations are common and hiding their existence from lesser civilizations, then surely at least one of those advanced species would break the trend and show themselves. If they are common, then they must all be hiding and that would imply that somehow everybody out there is in agreement to hide. How does that work?

Now, this is pure speculation, but say a single civilization developed in the Milky Way long before any others. Even a billion years or longer before anyone else is possible. Say they colonized the entire galaxy, but hide their existence until a civilization they're watching matures. As other civilizations mature and meet this ancient civilization, the old ones may impart their wisdom of hiding to all civilizations in the galaxy. As a result, developing civilizations think they are alone, until one day they find out that they are not.

While an interesting idea and I make this video as merely food for thought, I still suspect that intelligence is simply rare, and when it does develop it takes time and a lot of chance. Finding evidence of such a rare civilization is like searching for a needle in a haystack for SETI and that some day, perhaps sooner rather than later, we will wake up to a changed world where we know unequivocally that we are not alone.

Thanks for listening! I am futurist and science fiction author John Michael Godier currently issuing a rebuttal to those that think I'm a robotic voice simulator. Not quite, but close. It's more like The Matrix, Mr. Anderson.

Just kidding, I'm really just a vulcan and be sure to check out my books at your favorite online book retailer and subscribe to my channel for regular, in-depth explorations into the interesting, weird and unknown aspects of this amazing universe in which we live. 

TRANSCRIPT: Water Worlds, Desert Planets and ... Titan

One of the many questions that I wonder about is how rare Earth actually is.  Over the years, the consensus on that question has evolved somewhat from earth not being particularly special in the universe, perhaps even outright pedestrian, to earth looking increasingly special and rare with many factors playing into its habitability and ability to support the evolution of a technological species.

A new paper, link in the description below, authored by Fergus Simpson of the University of Barcelona may help shed some light on this question. This paper details an interesting prediction made by S. F. Dermott and Carl Sagan in 1995. At the time, it was thought that Saturn's moon Titan was likely to harbor hydrocarbons in liquid form. Just how much liquid would be present was open for debate and it ranged from vast oceans to Dermott and Sagan's idea that it wouldn't be anywhere near that extensive.

They predicted that if such oceans were present on Titan, its orbit would have been circularized by the action of tidal forces. That seemingly turned out to be correct, we know now that Titan's surface liquids are confined to a relatively sparse group of lakes. On the other end of the scale, we have Enceladus and Europa where there are strong indicators of deep subsurface liquid oceans, meaning that these two bodies are water worlds coated with a layer of ice with no known land.

The paper details that, statistically speaking, the division between land and ocean on a planet should be asymmetric. This implies that habitable exoplanets are either likely to either be water worlds where the surface is mostly, or entirely, covered in ocean or desert worlds where liquid water is present but scarce. Earth is the odd planet out given that we have a good amount of ocean but also lots of land.

Examples from science fiction of worlds like these would be dry, arid Tatooine from Star Wars or Thalassa from Arthur Clarke's novel "Songs of Distant Earth" which was a water world with a few human-inhabited islands, which may be the more common of the two in the universe.

While this does not preclude life arising on either water worlds or desert worlds, it does affect whether a technological civilization can arise. I've said in past videos that it would be exceedingly difficult for dolphins to master fire and smelt metal, regardless of their level of intelligence. On a water world, there may well be intelligence, but it might be locked in by its physiology perhaps awaiting direct contact with an alien species to liberate them from their world.

Now, much study of exoplanets will be needed to confirm or refute this paper, as Paul Gilster on his blog Centauri Dreams notes, we don't really yet have a complete picture of water delivery in the early solar system and that could affect the abundance of earth-like distributions of water within habitable zones.

Which brings me back to thoughts of strange Titan. It too is thought to have a subsurface very salty liquid water and ammonia ocean making it a sort of hybrid between a dry world and an ocean world. It may even harbor life, potentially several flavors of it in fact, one type on the surface, and another in the ocean. And it has another odd distinction, there will be a period 5 billion years from now where the sun will expand into a red giant. For a time during this period, its thought that Titan will be warm and become habitable and earth-like for a few hundred million years.

Will we some day retreat there to avoid the fury of the reddening sun and Earth's armageddon? Or will we be long gone and someone or something else arises on that little world? I find that future fun to ponder.

Thanks for listening! I am futurist and science fiction author John Michael Godier do check out my patreon page, link in the description below and be sure to check out my books at your favorite online book retailer and subscribe to my channel for regular, in-depth explorations into the interesting, weird and unknown aspects of this amazing universe in which we live.   

TRANSCRIPT: Are We the First Technological Civilization in the Solar System?

Digging through scientific papers as I do to research the content featured on this channel is something very much like hunting for Easter eggs. I would never call any scientific work mundane, any work done by scientists helps to advance our understanding of our world around us, but I might say that most subjects one sees in scientific papers just would not make for good YouTube videos unless done by a creator far better than I.

But several times a week I find papers, or easter eggs if you will, that excite me and then I go make videos on them. Occasionally, however, I will read a paper that absolutely blows my mind. That definitely happened this morning.

This paper is entitled "Prior Indigenous Technological Species" and was authored by Dr. Jason T. Wright of the Department of Astronomy and Astrophysics and Center for Exoplanets and Habitable Worlds at Pennsylvania State University, link to the paper in the description below. It's a good read folks.

But first some back story. It might surprise you, but it is fully scientific to consider the possibility of alien life having visited our solar system in the past. Carl Sagan and I.F. Schklovskii pointed this out in their book "Intelligent Life in the Universe" in 1966. This is independent of the question of whether the human race has ever interacted with an alien race. I have no problems with those that have concluded otherwise, but I have personally seen no compelling evidence that would lead me to conclude that we have. I have only seen material that leads me to more questions.

But the universe is a very old place, certainly old enough for other technological civilizations to have arisen long before ours did. It's also sufficiently old enough for an ancient civilization to have explored the galaxy end to end without exceeding the speed of light. Earth too, is sufficiently old enough to have been explored at some point in the distant past.

And, it's also fully within the realm of solid science to look for evidence of that as part of SETI operations, and indeed I've made several videos on this channel on the possibility of Bracewell or von Neumann probes hidden somewhere in the solar system. The tough question though is how likely is it that such a thing might exist?

This subject was tackled in a 2011 paper by Jacob Haqq-Misra and Ravi Kumar Kopparapu entitled "On the Likelihood of Non-Terrestrial Artifacts in the Solar System", link to the paper in the description below. They concluded that we simply have not explored our solar system thoroughly enough yet to detect such probes, if they exist, and that we should probably keep our eyes open for them just in case.

Dr. Wright in his new paper takes an interesting approach to the question of artifacts of other civilizations present in our solar system. He points out that while astrobiologists focus on searching for present or past evidence of simple life in our solar system, it may well be the case that artifacts of advanced civilizations are easier to find. And, going further, he suggests that the origin of such an artifact does not necessarily need to be another star system, but could be the solar system itself.

It is possible that advanced civilizations may have developed in the past on Earth, or even Mars or Venus which are thought to have once been earth-like. But Earth and Venus are geologically active worlds that renew their surfaces, so any evidence of an ancient civilizations is likely to be long gone on these planets. But you might find evidence of them on less active worlds like Mars or the Moon. Another possibility is that we might find an asteroid that was clearly mined at some point, perhaps by a von Neumann probe passing through.

Dr. Wright points out though that if we do find evidence, which we currently have absolutely none that stands up to scrutiny, then you must consider that the origin might not be another star system, but instead may be more likely to have originated from our own star system, especially considering that Earth would be a sort of elephant in the room since life has clearly arisen here.

While I consider it unlikely that there were ever precursor civilizations in our solar system, it is possible. And it's also possible that some day in the distant future others, perhaps from some formerly frozen moon made habitable by the brightening sun, might find evidence of us.

Thanks for listening! I am futurist and science fiction author John Michael Godier currently with a new book in the works, it's called Supermind and a 5000 word excerpt is up at Amazon Kindle Scout, link in the description below, check it out and if you like it give it a nomination! And be sure to check out my other books at your favorite online book retailer and subscribe to my channel for regular, in-depth explorations into the interesting, weird and unknown aspects of this amazing universe in which we live. 

TRANSCRIPT: Life on Jupiter?

Jupiter, at first glance, is perhaps the last place you would expect to find life. It's after all a roiling, hot gas giant. But it might surprise you that the gas giant itself has, at least in the past, been considered a possible home for life. And not just microbial life, but complex life. And while it's a long shot, it's not ruled out that something could inhabit the upper reaches of its atmosphere.

Jupiter is a generally misunderstood world. It's usually thought of as a huge ball of gas. But in reality, it's much more complicated than that. If you descend into Jupiter's atmosphere, you will first find a turbulent upper layer made up of a mix of gases, mostly hydrogen and helium. The further you go down, the hotter it will get due to the high pressures of the interior. At about 1000 kilometers below the top of the cloud deck you transition to one of the stranger natural substances thought to exist in our solar system. You would find metallic hydrogen.

Under the extremely high pressures of Jupiter's atmosphere hydrogen would be compressed into a soup of nuclei and electrons that exist in an ambiguous state that wouldn't have a clear boundary between a gas and a liquid. While metallic hydrogen is described as a liquid, it's a bit different than any other. It's better to think of the hydrogen as simply getting denser the deeper you go rather than use labels. Beyond that thick layer at the heart of the planet, it's thought you would find a core.

Not a lot is known about this core, but it's probably made of rock and metal just like the inner planets. It's not yet known if it's solid or completely molten or some mix of the two. Planetary cores are generally hard to study, and Jupiter's is among the hardest. But how could such an alien and strange environment such as Jupiter support any kind of life? The answer is in the conditions of the upper atmosphere.

In 1976, Carl Sagan and Edwin Salpeter released a paper, citation in the description below, in which they suggested that ammonia-based life of some kind might exist in the atmosphere of Jupiter. They envisioned three hypothetical kinds of animal that might live there which they termed sinkers, floaters and hunters. In particular, the floaters were envisioned as enormous gas bags, perhaps kilometers across and visible from orbit that suspended themselves in the atmosphere using helium.

Now, we have never seen floaters with any of our probes to Jupiter and this was a very speculative paper based on thinking deriving from what we know about our own oceans and life there. No such indications have ever surfaced that such a thing could really exist on Jupiter. But what does exist at Jupiter is the possibility of some interesting life related chemistry. The chemicals in the upper atmosphere of Jupiter do include water, ammonia and methane along with plenty of hydrogen in gas form.

These just happen to be the gases used in an interesting experiment done in 1952 by Stanley Miller and Harold Urey. They wanted to recreate the conditions of early earth and see if they could produce the initial prebiotic chemical reactions that are believed to have ultimately led to the dawn of life on earth.

What they did was pass water vapor through a mix of hydrogen, ammonia and methane gas. They then subjected that mix to periodic electrical discharges intended to simulate lightning. Then they looked at what came out the other side and it was, to say the least, interesting.

They found lots of organic compounds coming out of the mix. Most importantly, they initially found a number of the amino acids that are used by life. In 2007, however, the original sealed samples from the experiment were reexamined and as it turns out all 20 amino acids were present that are used by life on earth.

Since then, numerous revisions have been made to the model of what our planet's early atmosphere was like. As a result, a number of subsequent experiments have been done based on the Miller-Urey work ranging from changing the energy source to a volcano rather than lightning, adding in new chemical mixes that more accurately resemble what the early atmosphere is thought to have been like and so on. The results of many of these experiments has been the creation of even more types of organic molecules than Miller and Urey's experiment produced.

These experiments make it seem likely that at least the basic the chemistry for life first arose on some volcanic island on Earth billions of years ago. For Jupiter, this would be a more difficult process though it does have extremely powerful lightning and no shortage of heat. The problem is in its atmosphere, which is extremely violent. Gases circulate on that world by rising in certain areas and falling in others and any kind of life, microbial included, would have to deal with impossibly high temperatures and pressures when circulating deep below.

As Sagan noted in a segment on this topic in his television series Cosmos, such organisms would have to reproduce very rapidly. And while the prospect of life living in the atmosphere of Jupiter is somewhat of a stretch due to that roiling atmosphere, there may be gas giants and even brown dwarves in the universe calm enough to harbor at least some form of microbial life in their upper atmosphere, or possibly even more.

In a paper by Jack Yates and his colleagues at the University of Edinburgh from late 2016, link in the description below, they detail a hypothetical way for brown dwarves to harbor some form of life. They note that the upper atmospheres of some brown dwarves might harbor clement conditions with pressures and temperatures similar to earth. Relying on updrafts, life might exist in this zone within the brown dwarves.

This opens up vast new territory in the search for life in the universe. In 2013, a brown dwarf known as WISE 0855-0714 was discovered and seemingly has water-based clouds floating in its upper atmosphere. Using Sagan and Salpeter's research, they applied that thinking to the brown dwarf and concluded that yes, life might exist there.

The James Webb Space Telescope is slated to take an in-depth look at close brown dwarves, such as WISE 0855-0714 which is only 7 light years away. And while it's hard to envision native life having a way to evolve in the first place in a place like Jupiter or a brown dwarf, it's been suggested that dust floating in the atmosphere might do the trick for a solid place to do it or even microbial life being delivered by an asteroid through panspermia.

One can imagine that this kind of inhabited gas planet might be quite rare, but it does seem to at least be hypothetically possible and that in the future, when we do detect evidence of life, perhaps it might come from the spectra of a brown dwarf's atmosphere. But I'm left with one lingering, highly speculative thought after making this video. If Jupiter, then why not Saturn?

Thanks for listening! I am futurist and science fiction author John Michael Godier currently probably sounding a bit scratchy because it's spring and my allergies are working overtime and be sure to check out my books at your favorite online book retailer and subscribe to my channel for regular, in-depth explorations into the interesting, weird and unknown aspects of this amazing universe in which we live. 

TRANSCRIPT: Life on Io?

One of great unknowns of our solar system is whether it hosts other life, particularly microbial. I say the words other life carefully because there are two types of potential life in our solar system for us to consider. The first of these is life that evolved independently of earth life without any influence from here. This would be truly alien life and would give us an indicator that microbial life in the universe at large is probably common.

The other potential for life in the solar system is life transported from earth via panspermia getting deposited somewhere else and gaining a foothold. Our planet is teeming with microbial life, some of it extreme and possibly able to survive the rigors of space. It's entirely possible that we, the human race, will not claim the title of being the first life from earth to colonize other worlds.

This has led me to research just where either of those forms of off-earth life might exist in our solar system. There are obvious candidates such as Mars or Europa, but there were other candidates that surprised me when I went searching for the science on the subject. This video is the first in a series on this channel exploring those places, and this candidate is one that if it does harbor life, it's probably going to be centuries before we know about it.

That's because it would be exceedingly hard to verify its existence. It's Jupiter's moon Io and the reason for why it's going to be a while is that there is just no compelling reason to try to land on this moon. Studies from spacecraft passing by from afar are feasible, but expensive and with life there only just being within the realm of possibility it seems that Io will not be a priority for exobiological study for some time.

First there's just not much on the surface, it's basically just a big ball of mostly sulfur compounds. And a lander might well melt as it's the most volcanically active body in the solar system kept so by intense gravitational flexing it as it orbits. But volcanism is a dual-edged sword. While it can easily kill life, it can also provide an energy source for its genesis and indeed some models for how life arose on earth depend on the presence of volcanoes.

A possible way for life to survive on Io was presented by Dr. Dirk Schulze-Makuch in a 2010 paper in the Journal of Cosmology, link in the description below. The key to the possibility of microbial life on Io is linked to its history. Io is old, having formed about 4.5 billion years ago and today it has the least water out of any object in the solar system.

But that may not have always been so.

Objects in the outer solar system are typically rich in water ice anyway, and the models suggest that Io formed in an area where water ice was particularly plentiful in the Jupiter system. Given geothermal heating, some of that water might have been liquid opening up the possibility for the chemistry of life to get going, at least for a while, this would have had to happen within the first ten million years of that moon's existence. And, as we learn more about the early conditions present in the Jupiter system, it may be the case that it was  always impossible for life to arise on Io. But, at least right now, there is a chance.

Now, life on Io's surface is improbable and not just because of the volcanic activity. Jupiter blasts its surface with very high levels of radiation, and that likely precludes any possibility of panspermia or at least makes the chances low unless it happened very early on and native life could not arise there now. But beneath the surface of Io the conditions might be just  right for microbes originating from Io's early history to hold out.

Jupiter's radiation long ago deprived Io of its surface water, but below the surface there may be carbon dioxide and water in liquid form. And Io could well have several other potential liquid solvents for life including hydrogen sulfide, sulfur dioxide and even sulfuric acid.

Another important factor to consider would be the presence of lava tubes. Lava tubes are rich abodes of life here on earth and may also be so on Io. They provide protection from radiation and can be moist environments and also temperatures within the tubes could be both constant and warm.

But that's not the only way. The paper advances another model where the microbes might exist as dormant spores underground for very long periods only to be activated when lava is flowing on the surface above warming any fluids below to liquid temperatures and allowing a blossoming of life for a time before it once again goes dormant.

So while life on Io is a long shot, and there are far better candidates in our solar system that we must look at first, Io may one day prove to be more interesting than we might have imagined.

Thanks for listening! I am futurist and science fiction author John Michael Godier currently with a new book in the works, it's called Supermind and a 5000 word excerpt is up at Amazon Kindle Scout, link in the description below, check it out and if you like it give it a nomination! And be sure to check out my other books at your favorite online book retailer and subscribe to my channel for regular, in-depth explorations into the interesting, weird and unknown aspects of this amazing universe in which we live.