Sciency Words: The Silurian Hypothesis

Sciency Words: (proper noun) a special series here on Planet Pailly focusing on the definitions and etymologies of science or science-related terms.  Today on Sciency Words, we’re talking about:


I’ve heard several variations on this joke.  Why did the dinosaurs go extinct?  Because they didn’t put enough money into their space program.

But what if that isn’t a joke?  What if the dinosaurs (or some other prehistoric creatures) did establish an advanced civilization right here on Earth millions of years before we came along?  Could such a civilization come and go without leaving any trace for us modern humans to find?  Or could the traces be there for us to see, and we just haven’t recognized them yet?

In 2018, NASA astrobiologists Gavin Schmidt and Adam Frank presented this idea in a formal scientific paper titled “The Silurian Hypothesis: Would it be possible to detect an industrial civilization in the geological record?”  As Schmidt and Frank explain in a footnote:

We name the hypothesis after a 1970 episode of the British science fiction TV series Doctor Who where a long buried race of intelligent reptiles “Silurians” are awakened by an experimental nuclear reactor.  We are not however suggesting that intelligent reptiles actually existed in the Silurian age, nor that experimental nuclear physics is liable to wake them from hibernation.

Schmidt and Frank go on to examine some of the ways human industrial activities have changed this planet, and how those changes are being recorded geologically.  They also examine a few of the oddities and anomalies in the geological record as we currently know it.

To be clear, there is absolutely no definitive evidence that another advanced civilization existed on Earth before our own.  Schmidt and Frank go to great pains to emphasize that they don’t actually believe their own hypothesis to be true.

The Silurian Hypothesis is intended to be more of a thought experiment than anything else.  It’s meant to help us better understand how human civilization is changing this planet, and also (remember Schmidt and Frank are NASA astrobiologists) how alien civilizations might be changing their own worlds.

P.S.: The Silurian Hypothesis is also a wonderful example of how science fiction can inspire real life science.

Meet Umbriel, a Moon of Uranus

Lately, I’ve been trying to learn as much as I can about the planet Uranus and its moons.  It’s been a real challenge.  Only one spacecraft has ever visited the Uranian System, and that was back in 1986.

When I do research on most other objects in the Solar System, I usually find plenty of good, highly detailed information to work with.  Geology, chemistry, meteorology (sometimes), seismology (sometimes), astrobiology (more often than you’d think)….  But when it comes to the moons of Uranus… well, we know what color they are!

Today, I’d like to introduce you to Umbriel.  She’s sort of dark grey.  All the moons of Uranus are grey, but Umbriel is the darkest shade of grey out of them all.  In fact, that’s basically what the name Umbriel means: darkness.

According to this paper, Umbriel’s dark grey color might be caused by carbon compounds.  Imagine there’s coal or charcoal dust sprinkled all over Umbriel’s surface.  That’s basically what we think we’re looking at, except unlike coal or charcoal, Umbriel’s carbon compounds probably formed due to the photolysis and/or radiolysis of carbon dioxide, not because of biological activity.

But that dark coloration appears to be only skin-deep. Near the equator, Umbriel has a lighter, icier-looking surface feature.  It’s believed to be the result of a relatively recent asteroid or comet impact.  The color change probably means we’re seeing subsurface material that hasn’t undergone photolysis yet.  Officially, that surface feature is known as Wunda Crater.  Unofficially, it’s called the fluorescent Cheerio. Seriously, I’m not making that up.

Sending a spacecraft to Uranus is a costly and technologically challenging endeavor.  That’s why we’ve only done it once.  But if/when another Uranus mission does get off the ground, investigating that fluorescent Cheerio should be a top priority.  Anything that can tell us what lies beneath the surface of an icy moon like Umbriel is worth a closer look.

Wisdom of Star Trek: The Motion Picture

Star Trek: The Motion Picture is not exactly the most beloved film in the Star Trek franchise.  It’s slow-paced.  It feels kind of sterile.  The uniforms look just awful.  But I recently found out about the director’s cut, and I have to say it’s a huge improvement.

Granted, the movie still has its problems.  Among other things, those uniforms still look awful.  But at least I felt like I was watching Star Trek and not a bad rip-off of 2001: A Space Odyssey.  And the movie was thought-provoking in the way that Star Trek—and in fact all of science fiction—ought to be.

The movie’s antagonist is a vast, near-unknowable alien intelligence, an intelligence which has come in search of its Creator, and which is threatening to wipe out all life on Earth if the Creator’s identity is not revealed.  Speaking of this vast, alien intelligence, Mr. Spock explains:

It only knows that it needs, Commander.  But like so many of us, it does not know what.

If I may get a little personal for a moment, I’ve been feeling a bit discouraged lately.  Discouraged about what?  My writing journey?  My career?  My personal relationships?  Take your pick!  I just feel like something is missing.  I need something, and frustratingly I don’t even know what that something is.

But after watching the director’s cut of Star Trek: The Motion Picture, I’ve decided that’s okay.  That’s part of life.  We all go through this at some point or another.  This need for something—and the frustration of not even knowing what it is we need—is such a universal experience that even the most alien of alien intelligences may feel the same way sometimes.  I don’t know about you, but I find that to be a comforting thought.

P.S.: Well, it’s a comforting thought until some alien intelligence decides to take out its frustration on us Earthlings.

Sciency Words: Stagnant Lid

Sciency Words: (proper noun) a special series here on Planet Pailly focusing on the definitions and etymologies of science or science-related terms.  Today on Sciency Words, we’re talking about:


Here on Earth, we have earthquakes.  Lots and lots of earthquakes.  And that’s very odd.

Maybe we should be thankful for all those earthquakes.  Our planet’s system of plate tectonics is unique in the Solar System.  Frequent earthquakes are a sign that Earth’s tectonic plates are still moving, that our planet is still geologically healthy.  The alternative would be stagnant lid tectonics, and that’s something we Earthlings probably don’t want.

In this 1996 paper, planetary scientists V.S. Solomatov and L.N. Moresi coined the term “stagnant lid” to describe what was happening on Venus—or rather what was not happening.  Venus doesn’t have active plate tectonics.  Maybe she did once, long ago.  If so, Venus’s plates somehow got stuck together, forming a rigid, inflexible shell.

The term stagnant lid has since been applied to almost every other planetary body in the Solar System, with the obvious exceptions of the four gas giants, and the possible exceptions of two of Jupiter’s moons: Europa and Ganymede.

According to this paper from Geoscience Frontiers, neither Europa nor Ganymede have truly Earth-like plate tectonics, but something similar may be happening.  The authors of that paper refer to the situation on Europa and Ganymede as “fragmented lid tectonics” or “ice floe tectonics.”  The upcoming Europa Clipper and JUICE missions should tell us more about how similar or different this is to Earth’s plate tectonics.

A stagnant lid does not necessarily mean that a planet or moon is geologically dead.  Venus and Io both have active volcanoes, for example, and it was recently confirmed that Mars has marsquakes.  But none of these stagnant lid worlds seem to be as lively as Earth—and I mean that in more ways than one.

If you buy into the Rare Earth Hypothesis, plate tectonics is one of those features that makes Earth so rare. Plate tectonics is something Earth has that other planets don’t, and thus it may be an important factor in why Earth can support life when so many other worlds can’t.

Meet Ariel, a Moon of Uranus

I have a friend who’s obsessed with The Little Mermaid.  So if I’m going to write a post about Ariel, one of the moons of Uranus, it would be a real shame if I couldn’t make some sort of Little Mermaid reference.

Unfortunately, we know precious little about Ariel, or any of Uranus’s moons, for that matter.  Only one spacecraft has ever visited: NASA’s Voyager 2, way back in 1986. And the data Voyager 2 sent back gives us a frustratingly incomplete picture.

What I can tell you is that Ariel’s surface is made of ice, specifically water ice and carbon dioxide ice.  One hemisphere appears to have more carbon dioxide than the other, according to this paper from Icarus.  And according to this profile piece from NASA, Ariel is the shiniest of Uranus’s moons–it reflects more sunlight than the others.  Oh, and Ariel’s surface appears to be younger than the surfaces of those other moons as well.  That might be important!

In fact, according to this article from Scientific American:

[The Voyagers 2] flyby revealed Ariel to be relatively smooth, as if its surface was being continually renewed by activity deep within.  It is currently believed to be the only ocean world in the Uranian system.

A word of caution: that Scientific American article says a lot of highly speculative, highly conjectural stuff. Take it with a grain of sodium chloride.

However, in the absence of better, more detailed information about Uranus and its moons, it sounds like Ariel could maybe possibly be Uranus’s version of Europa or Enceladus.  It could possibly be a moon with an icy crust floating atop an ocean of liquid water.  It might even be the kind of environment that could support life.  There might even be….

But no, I shouldn’t make a claim like that.  It would be irresponsible of me as a science blogger.  Voyager 2’s data was too limited, and subsequent observations by Hubble or other Earth-based telescopes can only tell us so much.  Until our next mission to Uranus (whenever that might be), we really can’t say what might be hiding beneath the icy crust of Ariel.

Sciency Words: Dreadnought

Sciency Words: (proper noun) a special series here on Planet Pailly focusing on the definitions and etymologies of science or science-related terms.  Today on Sciency Words, we’re talking about:


Okay, this isn’t really a scientific term.  It’s more of a science fiction thing.  This week, I ended up watching a video on YouTube about how science fiction borrows and sometimes misuses terminology from the navy.  If you’re a Sci-Fi fan, and especially if you’re a Sci-Fi creator, I think this video is worth your time.

For me, the most interesting of these terms was dreadnought, a word that literally means “I fear nothing.”  In Sci-Fi, dreadnoughts tend to be the biggest, scariest, most overpowered spaceships out there.  If you’re going into battle against a dreadnought, well… I guess it was nice knowing you.

In real life, the term dreadnought comes from the H.M.S. Dreadnought, a massively oversized, massively over-armed battleship that first went out to sea in 1906.  The idea for this ship was championed by Admiral Sir John Fisher, later known as Baron Fisher.

I couldn’t resist showing you Baron Fisher’s coat of arms. Note the family motto on the bottom. Image courtesy of Burke’s Peerage.

Admiral Fisher wanted an all-big-guns ship. No small guns.  No middling-sized guns.  Only the largest guns available at the time would be large enough for the H.M.S. Dreadnaught.  According to this article, the Dreadnought triggered something of an arms race between Britain and Germany, with each country trying to out-dreadnought the Dreadnought, so to speak.

Thus we have a case of what linguists call semantic generalization.  The specific name of one vessel became a generalized term for all the ships that followed a similar design philosophy.  And now the term has been adopted by the Star Trek and Star Wars universes, and many other Sci-Fi universes besides.

Personally, I think dreadnoughts in science fiction have become a bit cliché.  They’re the biggest, baddest ships in the galaxy, and yet somehow the good guys always find a way to blow them up.  But now that I know the history of the term, I kind of want to fit some dreadnoughts into my own Sci-Fi universe—probably in some clever, punny way that honors Admiral Fisher and the original H.M.S. Dreadnought.

#IWSG: An Open Letter to Anyone Who Ever Talks to a Writer

Welcome to the Insecure Writer’s Support Group!  If you’re a writer, and if you feel in anyway insecure about your writing life, click here to learn more about this awesome group!

Since last month’s meeting of the Insecure Writer’s Support Group, I’ve been getting out more, doing new things, meeting new people.  It’s not like I took the “your life is soooo boring” thing seriously.  I didn’t plan this or anything.  It just sort of happened.

Anyway, if I’m going to be meeting new people, having more of a social life, and all that stuff, then I think it’s time to revisit one of my older IWSG posts.  So here, once again, is an open letter to anyone who’s had a conversation with me.

* * *

This is an open letter to anyone who’s ever had a conversation with me.  You may or may not have been aware of this at the time, but I’m a writer. That means there’s something you should know: while we were talking, I was taking mental notes about you.

Okay, there’s no need to panic.  I’m not in the habit of taking people I know or people I’ve met and just dropping them into my stories.  Yes, some writers do that, but that’s not how my process works.

So I promise I will not create a character just like you; however, the things you said—especially the way you said them—may inform my character development process at some point in the future.  Well, maybe not in the future.  To be honest, I’m probably already using you as a source of inspiration.

If you used some particularly interesting turn of phrase of displayed some unique or striking mannerism while we were interacting, I may have actually written that down to ensure I wouldn’t forget.  I wouldn’t have done this in front of you. That would’ve been rude. But be aware that I probably did this behind your back, and I probably added you to a file folder when I got home.

I hope this doesn’t make you feel self-conscious or uncomfortable. It’s important to me that you behave naturally.  Or rather, I want you and need you to behave authentically, because authentic speech and behavior are precisely that I’m trying to replicate in my storytelling.

Thank you for your time.  I just thought you ought to know what you’re getting yourself into when you talk to a writer like me.


J.S. Pailly.

More Sci-Fi Wisdom from The Light Brigade

Last week, I shared some Sci-Fi wisdom from The Light Brigade by Kameron Hurley.  I’m madly in love with this book, in case anyone hasn’t noticed. Today, I’d like to share another quote from Light Brigade, something that I found particularly enlightening.

There’s a theory that consciousness itself begins with story.  Stories are how we make sense of the world.  All of us have an internal story that we have told ourselves from the time we were very young.  We constantly revise this story as we get older, honing and sharpening it to a fine point.  Sometimes, when we encounter something in our lives, or do something that does not match up with that story, we may experience a great sense of dissonance. It can feel as if you’ve lost a piece of yourself.  It can feel like an attack on who you are, when the real world doesn’t match your story.

This idea of stories—both the stories that society wants us to believe about ourselves and the stories about ourselves that we make up on our own—this becomes a recurring theme throughout The Light Brigade.  It’s also been a recurring theme in my personal life these last few years.

It strikes me as a very writerly way of looking at the world. But it’s also, I think, a scientist’s way of seeing things.  Much of The Light Brigade, and especially the section quoted above, reminded me of Isaac Asimov’s classic essay “The Relativity of Wrong.”

[…] when people thought the earth was flat, they were wrong.  When people thought the earth was spherical, they were wrong. But if you think that thinking the earth is spherical is just as wrong as thinking the earth is flat, then your view is wronger than both of them put together.

In a similar way, the stories we tell ourselves about who we are, what we stand for, and what our purpose is in this world—these stories are imperfect descriptions of reality.  And that’s okay.  It doesn’t mean these stories are entirely false or that they have no value.  It just means some stories are more accurate then others.

All we can hope for is that our stories are as close to the truth as possible.

Sciency Words: The Torino Scale

Sciency Words: (proper noun) a special series here on Planet Pailly focusing on the definitions and etymologies of science or science-related terms.  Today on Sciency Words, we’re talking about:


Are you worried about an asteroid or comet smashing into Earth and annihilating human civilization?  Well, you should be worried about that a little bit.  But only a little bit.  Let me tell you about the Torino Scale, and while that won’t put all your fears to rest, it may help put things in perspective.

In the late 1990’s, M.I.T. Professor Richard Binzel came up with a system which he initially called the Near Earth Object Hazard Index.  In 1999, Binzel presented his system to a conference on Near Earth Objects (N.E.O.s) in Torino, Italy.

People at that conference loved Binzel’s idea and voted that the system should be adopted by the scientific community at large. They also voted to rename Binzel’s system the Torino Scale.

The Torino Scale asks two questions about any given N.E.O.: how likely is it to hit us, and how much destructive energy would be released if it did?  Taking those two factors into consideration, the Torino Scale then produces a score between zero and ten.  Zero means we have nothing to worry about.  Ten means “WE’RE ALL GONNA DIE!!!  AAAHHHHHH!!!” as the experts would say.

According to Wikipedia, the comet that caused the Tunguska Event would have probably scored an eight, and the asteroid that caused the K-T Event (the event widely believed to have killed off the dinosaurs) would have scored a ten.  Wikipedia also tells me that the 2013 Chelyabinsk meteor would have scored a zero, because while that particular N.E.O. was definitely on a collision course with Earth, it’s destructive energy was relatively low (I wonder if the residents of Chelyabinsk, Russia, agree with that assessment).

As of this writing, there are no known N.E.O.s that score higher than zero on the Torino Scale, as least not according to this website from NASA’s Jet Propulsion Laboratory.  It is possible for an N.E.O.’s threat level to change as we learn more about it.  As explained in this article from NASA:

The change will result from improved measurements of the object’s orbit showing, most likely in all cases, that the object will indeed miss the Earth. Thus, the most likely outcome for a newly discovered object is that it will ultimately be re-assigned to category zero.

Sooner or later, another eight, nine, or ten on the Torino Scale will come along.  Fives, sixes, and sevens could also be bad news for us.  But for now, at least within the next one hundred years, it sounds like we probably don’t have too much to worry about.


The Turning Test

A friend and I were playing with the auto-complete functions on our phones.  This comic is inspired by one of our auto-completed text messages.