A to Z Challenge Theme Reveal

Hello, friends!

Do you have a favorite planet?  Each planet of the Solar System is beautiful in its own way, and weird in its own way, and dangerous in its own way.  It’s almost like each planet has its own distinct personality.  When you start learning about the planets, it’s hard to not pick a favorite.  My own favorite is Venus, but that’s not what I want to talk about today.  Today, I’m announcing my theme for this year’s A to Z Challenge, and that theme will be:


For those of you who don’t know, the A to Z Challenge is a month long blogging event.  Throughout the month of April, participants write twenty-six blog posts (starting with A, ending with Z) on a topic of their choice.  In previous years, I’ve used the A to Z Challenge as a platform to talk about scientific terminology, the search for alien life, and humanity’s future as a spacefaring species.  If you want to learn more about the A to Z Challenge, and if you’re interested in signing up yourself, please click here.

Now you may be wondering about the theme I picked this year.  Out of all space/science topics I could cover for an A to Z series, why the heck would I pick Mercury?  Mercury is not Mars, or Saturn, or Pluto.  Mercury is not a super exciting place.  There’s virtually no atmosphere.  There are absolutely no signs of life.  And if you’re thinking about future human habitats in space, Mercury may be the least appealing piece of real estate in the entire Solar System.

Observing Mercury with a telescope is inconvenient, due to Mercury’s proximity to the Sun.  Reaching Mercury with a spacecraft is also inconvenient, again due to the planet’s proximity to the Sun.  And what does all the inconvenience of observing Mercury or traveling to Mercury get you?  A grey rock.  There are a bunch of craters.  It gets really hot during the day, due (yet again) to the proximity of the Sun.  And there’s not a whole lot else worth saying about Mercury, right?

Wrong.  By the end of this year’s A to Z Challenge, I do not expect to change your mind about whatever your favorite planet happens to be.  My favorite planet will still be Venus.  But I do hope you’ll come to appreciate Mercury for what he truly is: a humble grey rock, with a few weird quirks, and a surprisingly big heart (by which I mean a surprisingly big planetary core–for such a small planet, Mercury has an enormous core!).

P.S.: I will be taking the rest of March off from regular blogging.  I’m still picking up the pieces after a recent family emergency, and I’ve decided that whatever free time I do have for blogging should go to preparing for this A to Z series.  So I’ll see you all on April 1st, when “A” will be for “amorphous ice.”

#IWSG: Write vs. Wrong

Hello, friends!  Welcome to this month’s meeting of the Insecure Writer’s Support Group, a monthly blog hop created by Alex J. Cavanaugh and co-hosted this month by Diedre Knight, Tonya Drecker, Bish Denham, Olga Godim, and JQ Rose.  If you’re a writer and if you feel insecure about your writing life, click here to learn more about this awesomely supportive group!

A family emergency happened last week, and I’m still a little bent out of shape because of that.  Getting back into writing after dealing with all that stress has been a struggle, so today I’m going to turn the floor over to my muse.  She has something she wants to say, and maybe it’s something your muse would like to hear.

* * *

Greetings to all my fellow muses, inner critics, and motivational demons.  I am James Pailly’s muse.  It’s my job to give James guidance and inspiration in his writing life, but I am not the only source of guidance and inspiration he turns to (nor should I be).  He reads and does research.  He talks to people.  He talks to other writers.  Sometimes he finds good, sensible advice in this way; other times, the advice he gets is not so sensible.

What works for one writer will not necessarily work for others.  Each writer is unique.  Each writer is special.  They have their own strengths and their own struggles.  But writers are human, and humans can be tempted by broad generalizations and oversimplified explanations—especially when their own unique struggles start to feel overwhelming.

My writer is often told that he should not edit while he writes, as if editing and writing are two separate and distinct activities.  First there’s a writing phase, then there’s an editing phase, and there’s supposed to be a hard line between the two.  Perhaps some writers really do work this way.  Perhaps a majority of them are able to operate this way.  But that is not the way my writer works, and it never will be.

My writer will write a sentence or two—a paragraph—an exchange of dialogue—then he’ll go back and rewrite it all before moving on to the next part.  He’ll finish a page, then go back and fix the page that came before it.  He’ll finish a chapter, then tweak an earlier scene.  Every word my writer writes is subject to change, at any time, for any reason, until the story is finished.  If that means we have to go back and rewrite half of the whole book, that’s fine.  The sooner we get started on those rewrites, the better.  And every time some writing guru tells my writer he’s doing it wrong, I am there to remind my writer what he should already know about himself.  

For my writer, writing and editing are thoroughly intermingled activities.  It’s a messy process.  It’s a labor-intensive process.  My writer does get frustrated, sometimes, and wish there were an easier way.  But this is what’s best for him, and deep down he knows it.

Should your writer write (and edit) the way mine does?  I can’t tell you that.  Ultimately, you will have to determine what is right and what is wrong for your own writer.

Sciency Words: The Gartner Hype Cycle

Hello, friends!  Welcome back to Sciency Words, a special series here on Planet Pailly where we talk about the definitions and etymologies of science or science related terms.  Today, we’re talking about:


In my last blog post, I shared my thoughts about A.I. generated art.  It’s a new technology.  There’s a lot of hype about this new technology right now, and my suspicion is that A.I. art is getting a little more hype than it really deserves.  I feel that way, in part, because of something called the Gartner hype cycle.

Definition of the Gartner hype cycle: The Gartner hype cycle is a curvy line on a graph that purportedly models how the hype for a newly introduced technology changes over time.  First, the hype will go up—way up.  Then the hype will plummet down.  In the final phases of the cycle, hype will go slightly up again, before leveling off.

Etymology of the Gartner hype cycle: The idea that new technologies experience a “hype cycle” was first introduced in 1995 by tech analyst Jackie Fenn.  She worked for a tech consulting firm called Gartner Inc., which continues to use hype cycle charts in presentations about new and emerging technologies.

As Gartner Inc. describes it on their website, the Gartner hype cycle has five distinct phases:

Innovation Trigger: A new technology is introduced.  Hype starts to grow (and grow and grow).

Peak of Inflated Expectations: The hype surrounding this new technology gets blown way out of proportion.  Media reports make it sound like almost all the world’s problems could be solved by this new technology.  Investors on Wall Street start screaming “Buy! Buy! Buy!”

Trough of Disillusionment: The hype bubble bursts.  It becomes clear that this new technology cannot solve all the world’s problems, and those Wall Street people start screaming “Sell! Sell! Sell!” 

Slope of Enlightenment: While the new technology can’t solve all of the world’s problems, it turns out that it can solve some problems.  Interest and investment in the new technology starts to build again, based on more realistic expectations.

Plateau of Productivity: The new technology becomes normalized after finding its proper niche in society.

There are at least three major criticisms of this concept.  First, the word “cycle” is misleading.  It implies that this process is cyclical when it clearly isn’t.  Second, this concept is not good science.  How do you measure something like hype, scientifically speaking?  And third, the Gartner cycle would have you believe that every new technology will eventually find its niche.  There’s no guarantee of that.  Sometimes a new technology simply fails.  It falls into that “trough of disillusionment” and never comes back.

Despite those valid criticisms, I do think the Gartner cycle can be a helpful first approximation of what might (might!) happen with a newly introduced technology.  The cycle may not be good science.  It may not make exact predictions, and it can’t guarantee anything.  But the general idea that the hype for a new technology will go way up, then go way down, and then settle somewhere in the middle… that does seem to happen, more often than not.  There’s enough truthiness to the Gartner cycle that it’s influenced my own thinking about A.I. art, as well as my thinking on topics like cryptocurrency, commercial space flight, self-driving cars, and a bunch of other things.

And the Gartner cycle is something I’m starting to think about in my Sci-Fi writing as well.  What might happen when we invent antigravity technology?  Faster-than-light travel?  Time machines?  Would those technologies experience something like the Gartner hype cycle?  Maybe.  Or maybe not.

Again, there are no guarantees with this one. In my mind, the Gartner cycle is a useful first approximation of what might happen. Nothing more.


I first heard about the Gartner cycle in a video by Wendover Productions, which uses drone delivery services as an example of the Gartner hype cycle in action.  Click here to watch.

I, For One, Welcome Our New A.I. Overlords

Hello, friends!

I was originally planning to post this last week, but then I got nervous.  I’m about to say something controversial.  I’m going to take a stance on an issue, fully aware of the fact that some of you will disagree with me—some of you may vigorously disagree.  That makes me a little bit nervous, but what makes me even more nervous is that I’m not 100% sure I agree with myself.  Even after taking an extra week to think things over, I still have doubts about what I’m about to say.  Okay, here goes: I am not super worried about A.I. generated art.

There’s a long history of people freaking out over new technologies.  I grew up in the 90’s.  I only vaguely remember the first time I heard about the Internet.  What I remember is that the Internet sounded scary.  No one seemed to fully understand what this Internet thing was or how it worked, but whenever adults started talking about it, they all had strong opinions.  Strongly negative opinions, it seemed.  Things were going to be different because of the Internet.  Things were going to change.  And if there’s one constant in life, it’s that change scares people.

And I’m not immune to that fear.  A few weeks ago, I saw a news article about a newly discovered exoplanet.  Photographing exoplanets is still, in most cases, beyond our current technology, so NASA sometimes publishes “artist conceptions” of what newly discovered exoplanets might look like.  Not this time, though.  This time, they used an A.I. generated image.  The image was beautiful.  I’m sure it was scientifically accurate, too.  And it left me feeling like I’d just been punched in the gut.  Drawing or painting what exoplanets might look like?  That’s a job, and it’s a job that will probably go away soon, because it’s a job an A.I. can easily do.

So I am worried about what A.I. means for creative folks like me.  However, I’ve also seen a little too much hyperbolic fear-mongering about A.I. generated art, writing, and music.  Despite what a lot of people are saying right now, I am not worried about A.I. replacing human artists entirely.  For the purposes of this blog post, I’d like to draw a distinction between creating art and producing content.  In theory, I could have an A.I. write blog posts for me, and I could have an A.I. generate silly cartoons for my blog, too.  Would you, dear reader, find those blog posts interesting and informative?  Would those A.I. generated cartoons make you smile?  Maybe.  But I suspect the novelty of that would only last so long.

I write and draw because I have things I want to say, and I don’t know any other way to say them.  Art exists to express feelings and ideas that would otherwise be inexpressible.  At its core, art is a form of communication.  An A.I. can produce content.  It may even produce informative or entertaining content.  But if I filled this blog with A.I. generated blog posts and A.I. generated cartoons, all the the thoughts and feelings I wanted to express would remain unexpressed, and the kind of human-to-human connection that art facilities would not occur.

So for that reason, I’m not super worried about A.I. generated art.  I am a little worried, because things are going to change, and certain niches in the art world (like artist conceptions of exoplanets) may disappear.  But this isn’t the end of art anymore than the Internet was the end of… whatever grownups in the 90’s thought the Internet would be the end of.  There will always be a need for and a desire for human-made art, because art is fundamentally a form of self expression.  It’s a form of communication.  A.I. can produce content, but it can never replace the human-to-human connection of genuinely human-made art.


My deepest concerns about A.I. art have little to do with the technology itself and more to do with the law.  Fortunately, the YouTube Channel Legal Eagle just did an episode about what the law has to say about A.I. generated art. Click here to watch!

And YouTuber Tom Scott recently did an episode about sigmoid curves and what they have to do artificial intelligence.  Click here for that.

Sciency Words: Coronium

Hello, friends!  Welcome to Sciency Words, a special series here on Planet Pailly where we take a closer look at the definitions and etymologies of scientific terms.  Today on Sciency Words, we’re talking about the word:


Here on Sciency Words, we usually talk about scientific terms that are relevant and useful in modern science, but sometimes I like to draw attention to scientific terms that didn’t make it.  I think it can be helpful to learn about how and why words drop out of the scientific lexicon.  So today, we’re going to talk about coronium, a chemical element that we now know does not exist.

Definition of coronium: A chemical element that scientists in the late 19th and early 20th Centuries thought existed based on a mysterious green emission line detected in the Sun’s corona.  At least one very prominent scientist (Dmitri Mendeleev) believed coronium to be an element lighter than hydrogen, with chemical properties similar to helium and argon.

Etymology of coronium: In 1869, American astronomers Charles Augustus Young and William Harkness independently detected a green emission line in the Sun’s corona during a solar eclipse.  In 1887, Professor A. Grünwald proposed the name “coronium” for whatever chemical substance caused that green emission line.  Since this unknown substance was first detected in the Sun’s corona, coronium seemed like an obvious name.

The “discovery” of coronium came right on the heels of the discovery of helium, and the story of these discoveries was eerily similar.  Scientists observe a solar eclipse.  A strange, new emission line appears in Sun’s spectrum, as measured using a spectroscope.  This emission line is (or seems to be) the first evidence of a newly discovered chemical element.

Dmitri Mendeleev was initially skeptical about both helium and coronium, because he couldn’t find places for them in his periodic table of the elements.  Toward the end of his life, however, Mendeleev tried to shoehorn these elements, along with several others, into his theories by adding a “group zero” to the periodic table.  Each group zero element is lighter than the group one element it sits next to—for example, argon is lighter than potassium, neon is lighter than sodium, helium is lighter than lithium… and coronium ended up sitting next to hydrogen, indicating that coronium is an element lighter than hydrogen.

Mendeleev was a smart man, but he was wrong about group zero.  After some reshuffling of the periodic table, most of the group zero elements were moved to group eighteen (a.k.a. “the noble gases”), and in the end, it turned out there really was no place for coronium.  No element lighter than hydrogen exists.

So what caused that anomalous green emission line in the Sun’s spectrum?  Turned out it was iron.  In the 1930’s, German and Swedish astronomers Walter Grotian and Bengt Edlén discovered that a form of super-hot, super-ionized iron gives off an emission line at 530.3 nm—an exact match with the 530.3 nm green emission line found in the solar corona.  Without the power of the Sun (or the power of modern laboratory equipment), iron doesn’t get hot enough or ionized enough to reveal that part of its spectrum.  As a result, scientists in the late 1800’s couldn’t have known what that strange, green emission line was.

Coronium is a Sciency Word of the past, from a time when the spectroscope was a relatively new scientific instrument and the periodic table was still a work in progress.  We no longer need to imagine there’s an exotic chemical element found only in the Sun’s corona, not when super-ionized iron explains that green emission line in the Sun’s spectrum just as well.


Here’s an interesting article about Dmitri Mendeleev and his mistakes, including his mistakes about coronium and the “group zero” elements.  For anyone involved in science education, this article makes a compelling case about why teaching the history of science is so important, with an emphasis on showing how scientists don’t always get it right on the first try.

I also want to recommend this book, simply titled The Sun.  It is full of cool and useful space facts that I had never read about before anywhere else (including the false discovery of coronium).  The Sun is part of a series called Kosmos, and I highly, highly, highly recommend this series to anyone who loves space.

And lastly, here’s a link to A. Grünwald’s 1887 paper where he first proposed the name “coronium” for a “hitherto unknown corona-substance.”

Sciency Words: Antitail

Hello, friends!  Welcome to Sciency Words, a special series here on Planet Pailly where we talk about the definitions and etymologies of scientific terms.  In today’s Sciency Words post, we’re talking about the word:


Did you see the comet?  Pretty much everyone I know has been asking me that question lately.  Comet C/2022 E3 (ZTF) had a wild ride these last few weeks.  First, she started glowing a lot brighter and a lot greener than expected, leading to some people calling her “the green comet.”  Then, due to some intense solar activity, a gap formed in one of the green comet’s two tails.  Shortly thereafter, almost as if the comet were trying to compensate for the damage to one tail, an apparent third tail became visible to observers here on Earth.  This apparent third tail is what astronomers call an antitail.

Definition of antitail: Comets typically have two tails: a dust tail and an ion tail.  These tails are supposed to point away from the Sun.  They’re caused by the solar wind sweeping gas, dust, and other lightweight material away from the comet and off into space.  An antitail is an apparent third tail pointing toward the Sun.  At least antitails look like they’re pointing toward the Sun, but this is actually an optical illusion.

Etymology of antitail: The prefix “anti-” can mean several things.  In this context, it means “opposite,” because antitails point (or look like they point) in a direction opposite to the direction cometary tails are supposed to point.  Based on my research, I believe this term was first introduced in the late 1950’s, following the appearance of comet Arend-Roland.

Okay, I’m going out on a bit of a limb claiming that the term was introduced in the 1950’s.  I cannot find any sources explicitly stating that, but almost every source I looked at seems to agree that Comet Arend-Roland had the most famous and noteworthy antitail in the history of antitails.  In 1957, Arend-Roland developed a large and protruding “sunward spike.”  In photos (like this one or this one), the comet reminds me a little of a narwhal.

Arend-Roland cannot possibly be the first comet ever observed to have an antitail, but it does seem to be the most spectacular and most widely studied antitail in recorded history.  Crucially, I was unable to find any sources mentioning cometary antitails prior to 1957.  Ergo, I think I’m right that the term was first introduced around that time, in reference to that particular comet.  But I could be wrong, and if anyone knows more about this topic than I do, please do share in the comments below.

Regardless of how much of a first Arend-Roland’s antitail really was to the scientific community at the time, it was not much of a mystery.  Within a matter of months, scientists were able to offer explanations, like this explanation published in Nature:

No extraordinary physical theory appears necessary to account for the growth of the sunward tail […]  The sunward tail must almost certainly have resulted from the concentration of cometary debris over an area in the orbital plane.  Seen at moderate angels to the plane, the material possessed too low a surface brightness to be easily observed, but seen edge-on it presented a concentrated line of considerable intensity.

So several things have to happen in order for us Earth-based observers to see an antitail.  First, a comet needs to shed some debris that’s too big and heavy to be swept off by the solar wind.  This extra debris will accumulate along the comet’s orbital path, rather than billowing off in a direction pointing away from the Sun.  Second, Earth has to be in just the right place at just the right time to see this debris field “edge-on.”  Otherwise, the light reflecting off the debris will be too diffuse for us to see.  And third, this has to happen at a time when the comet’s tails don’t overlap with the debris field (i.e., the debris and the tails have to be pointing in opposite directions, as seen from Earth).  Otherwise, the glow of the tails will obscure the light reflecting off the debris.

Last week, I was lucky enough to see the comet, but I didn’t see her bright green color (she was a hazy grey in my telescope), and I certainly didn’t get a chance to see the antitail.  I’m pretty sure I was a few days too late for that, and besides, there’s too much light pollution where I live to see faint details like that.

Still, I consider it a great joy and privilege that I got to see as much of the comet as I did.  And for all the cool sciency stuff I couldn’t see for myself, I can always turn to my research if I want to learn more.


Here’s the 1957 report from Nature that I quoted above, explaining what “must almost certainly” have caused Arend-Roland’s “sunward tail.”

And here’s a more recent article about Arend-Roland, reviewing the comet’s discovery, observation history, and the appearance of his antitail.

Lastly, here’s an article from Live Science about the recent “green comet” and her antitail.

#IWSG: The Patience of a Muse

Hello, friends!  Welcome to this month’s meeting of the Insecure Writer’s Support Group, a blog hop created by Alex J. Cavanaugh and cohosted this month by Jacqui Murray, Ronel Janse van Vuuren, Pat Garcia, and Gwen Gardner.  If you’re a writer and if you feel insecure about your writing life, then click here to learn more about this wonderfully supportive group!

I like to write, but I don’t like to talk about writing.  Whenever I talk about writing, I end up reminding myself just how tedious and frustrating the writing process can be.  Fortunately, my muse is always eager to talk about writing, even when I’m not in the mood, so today I’m going to turn the floor over to her.  My muse has something to say, and perhaps it’s something you and your muse would like to hear.

* * *

They don’t tell you this in muse school, but we muses need to play the long game with our writers.  Writers are born to write, but that does not mean they’re born with all the skills and abilities necessary for writing.  The day I first met my writer—the human I was assigned to guide and inspire throughout his creative life—I found him utterly unprepared and woefully ill-suited for writing.

We had to start with the basics.  I began by encouraging my writer to take an interest in the alphabet.  He had these wooden blocks with letters on them.  Those helped.  Then I got him interested in words.  Spelling was a challenge for many, many years, but we worked through that.  Then came grammar, syntax, rhymes and rhythm—allegory, metaphor, irony, parallelism—comedy and tragedy—classic literature and genre fiction…  We made progress.  My writer has learned much since I first met him; he also still has much to learn.

But writers are human, of course, and they can be stupid in the way all humans are stupid.  They like instant gratification.  They want quick, easy solutions to their problems, including their writing-related problems.  But writing is a skill that improves slowly.  Gradually.  The growth of a writer happens so slowly and so gradually that it may be almost imperceptible, even to writers themselves. Some writers may fool themselves into believing that they’re not improving at all, or they may start to fear that improvement is not possible.  They forget how far they’ve come, and they worry themselves sick over how much further they still has to go.

Needless to say, as a muse, you must never give up on your writer.  More importantly, though, never let your writer give up on him or herself.  Make your writer keep writing.  Make your writer keep practicing, keep trying.  Do that, and the writing will get better.  I promise.

Science Can’t Explain Everything

Hello, friends!

As you know, I love science.  I’m a little obsessed.  But there are people who get annoyed or even offended by my obsession with science, and every once in a while one of these people will remind me, sternly, that science can’t explain everything.  And you know what?  I generally agree with that sentiment.  But then people start declaring that science will never know this specific thing or that specific thing, and I immediately think of a certain 19th Century French philosopher named Auguste Comte.

Comte was not some scientifically illiterate buffoon.  He wasn’t one of those 19th Century evolution deniers, or one of those latter-day opponents to the heliocentric model of the Solar System.  In fact, Comte is regarded today as the very first philosopher of science, in the modern sense of that term, and he gets credit for coining the word “sociology” and for laying the philosophical foundation for that entire branch of science.  There’s also a wonderful quote from Comte about the mutual dependence of scientific theory and scientific observation.  Basically, you can’t formulate a theory without observation, but you also can’t make an observation without the guidance of a theory.

But that is not the Comte quote I think of whenever somebody starts lecturing me about the things science will never know.  It’s this quote about the stars: “[…] we shall never be able by any means to study their chemical composition or their mineralogical structure…”  Comte also declared that: “I regard any notion concerning the true mean temperature of the various stars as forever denied to us.”

Comte wrote this in 1835, and if you can put yourself into an 1835 mindset you can see where he was coming from.  There’s no such thing as rocketry.  We don’t even have airplanes yet.  And even if you could fly up to a star (or the Sun), how would you measure its temperature?  What kind of thermometer would you use?  And how would you go about collecting stellar material, in order to determine the star’s chemical composition?

According to Comte—a highly intelligent and very pro-science person—this sort of knowledge was utterly impossible to obtain.  And yet only a few decades later, thanks to the invention of the spectroscope, scientists started obtaining some of this unobtainable knowledge.  For those of you who don’t know, spectroscopes separate light into a spectrum.  Some parts of the spectrum may appear brighter or darker than you might otherwise expect, depending on which chemical substances emitted or absorbed the light before it reached the spectroscope.  And so by comparing the spectral lines of chemicals we have here on Earth to the spectrum obtained from the light of a star, you can determine the chemical composition of that star.

You can also measure a star’s temperature thanks to a concept known as black body radiation.  Basically, black body radiation refers to the fact that things glow as they got hotter.  If no other light sources are involved, then the color of a glowing object will be directly related to that object’s temperature.  Ergo, if you know what color a star is, then you can work out a pretty accurate estimate of what temperature that star must be.

Auguste Comte didn’t foresee any of this.  It is certainly true that science does not know everything, and there are surely things that science will never know.  But if you think you know, specifically, what science can never know, I question that.  Someday, some new invention (like the spectroscope) or some breakthrough discovery (like black body radiation) may turn an utterly unknowable thing into a matter of trivial measurements and calculations.

Maybe the one thing science truly can never know is what science’s own limitations are.


Here’s a very brief post about Auguste Comte, what he said about stars, and how epically wrong he was with that one prediction.

Also, here’s a short article about some genuine limitations that science has, like aesthetics, moral judgements, etc.

Sciency Words: P-P Chain

Hello, friends!  Welcome to Sciency Words, a special series here on Planet Pailly where we discuss the definitions and etymologies of scientific terminology.  In today’s post, we’ll be discussing the scientific term:


I have, in the past, been accused of covering scientific terms on the basis of how silly they sound, rather than on the basis of pure scientific merit.  But I would never do such a thing.  I have far too much respect for both science and linguistics.  Now with that unambiguously established, let’s talk about the p-p chain.

Definition of the p-p chain: In the field of nuclear physics, the p-p chain refers to a series of nuclear fusion reactions, starting with the fusion of two protons and leading, ultimately, to the creation of a helium-4 nucleus.  The p-p chain is by far the most common fusion process occurring in the core of the Sun, as well as other stars of similar or smaller sizes.

Etymology of the p-p chain: The p’s in p-p chain refer to the two individual protons that fuse together in the very first step of the process.  English astronomer Sir Arthur Eddington first proposed that proton-proton fusion might be occurring inside stars, writing about it in a 1926 article titled “The Internal Constitution of the Stars.”  German-American theoretical physicist Hans Bethe worked out the step by step details of the process in a 1939 paper called “Energy Production in Stars.”  Sadly, I cannot give credit to either Eddington or Bethe for coining this term.  They came up with the idea and worked out the details, but I have not been able to determine who, exactly, first introduced the term “p-p chain” into the scientific literature.

There are at least three versions of the p-p chain, each with different intermediate steps between the individual protons at the start and the helium-4 nuclei at the end (a fourth version is possible in theory, but has yet to be verified in reality).

Recently, scientists at the National Ignition Facility (NIF) in California made significant progress in nuclear fusion research.  That recent experiment has been described as recreating the power of the Sun here on Earth, which is true enough.  But NIF did not recreate the entire p-p chain from start to finish; they did something loosely equivalent to the very last step only.  It seems that reproducing the whole chain is still beyond our current scientific abilities.

So the next time you notice the Sun, shining yellow-gold in the sky, just remember that she can still do p-p chains in ways we humans cannot.


If you’re looking for a more detailed and technical explanation of the p-p chain (and the three or four variations thereof), check out this article from encyclopedia.pub.  That article was my main source of information while writing this post.

You can also find Arthur Eddington’s “The Internal Constitution of the Stars” by clicking here and Hans Bethe’s “Energy Production in Stars” by clicking here.

And if you’re looking for a fun way to try nuclear fusion for yourself, check out the game Fe[26].  You slide around tiles marked with the names of different atomic nuclei, trying to combine them to make bigger and bigger elements.  Which nuclear combinations work and which ones don’t?  Play and find out for yourself!

Are We Alone in the Universe?

Hello, friends!

I have only recently returned to regular blogging, and in several recent posts I’ve alluded to the fact that I’m planning to take my Sci-Fi writing in a new creative direction.  A lot of things are changing for me right now.  A lot of the things I’m doing (or trying to do) are new.  With that in mind, I feel like this is a good time to restate some of my views and beliefs about science and the universe, starting with my views and beliefs about extraterrestrial life.

When people ask “Do you think we’re alone in the universe?” I get slightly annoyed by that question.  It’s too big a topic to reduce to a simple yes or no question.  In Humanity’s search for extraterrestrial life, there are really three kinds of life we might find out there:

Microbial Life: Almost as soon as Earth existed, terrestrial microorganisms existed, too.  Microbes developed so swiftly and so easily on this planet that the same thing must have happened elsewhere.  For this reason, I believe extraterrestrial microorganisms are plentiful across the cosmos.

Multicellular Life: Complex multicellular organisms—fish, plants, bugs, etc—exist on Earth due to a happy accident.  About 2.4 billion years ago, some of Earth’s microbes started burping up oxygen.  To those microbes, oxygen was a waste product, but that waste product could also be used in biochemical reactions to create energy.  Lots of energy.  Enough energy to make complex multicellular life possible.  If multicellular life requires this sort of happy accident in order to exist, then I suspect multicellular life must be rare across the universe.

Intelligent Life: I’m going to define intelligence as the ability of a species to make and use tools, to communicate complex ideas, and to generally improve upon its knowledge and technology over time.  As far as we can tell, life like that only evolved one time on our planet.  Given the vastness of the entire universe, I think intelligent life must exist elsewhere, but I also think it must be extremely rare.

Some time around 1950, nuclear physicist Enrico Fermi famously asked “Where is everybody?” in reference to alien life.  As Fermi saw it, advanced alien civilizations should be out there, and their activities in space should be obvious to us.  And yet when we look out into the universe, we see nothing.  This apparent contradiction—aliens should be everywhere, and yet they seem to be nowhere—is today known as the Fermi Paradox.

So I guess my answer to questions like “Where is everybody?” or “Are we alone in the universe?” depends on what kind of alien life we’re talking about.  If we’re talking about alien microorganisms, I think they’re plentiful, and I think it’s only a matter of time before we find evidence of alien microbes on Mars or on one of the icy moons of the outer Solar System.  If we’re talking about multicellular life, that sort of life is rare.  And intelligent life must be rarer still—so rare, in fact, that our nearest intelligent neighbors may be hundreds, thousands, or even millions of lightyears away.

But these are just my opinions.  My opinions about this topic have changed over time, and as I keep learning, my opinions and expectations will, no doubt, change again.

So, friends, what are your opinions and expectations concerning extraterrestrial life?  Do you think I’m on the right track, or is there something I’ve missed that you think I should learn more about?