Science Fiction and the Death of the Sun

Science Fiction and the Death of the Sun

By Gwen C. Katz

Why is early speculative fiction so grim?

From potions that turn people into psychopathic murderers to alien invasions only defeated by coincidental quirks of biology, turn-of-the-20th-century sci-fi carries a distinct tone that the arc of history bends towards catastrophe. Most commentators have looked to social and political factors to explain this tone. There are plenty to choose from—runaway income inequality, rampant corruption, crushing working-class living conditions. These issues were certainly present in the minds of early sci-fi authors, many of whom—such as H.G. Wells, who drafted a precursor to the UN Declaration of Human Rights—were progressive reformists. 

But there’s another factor that isn’t often mentioned: They thought the sun was on the brink of death.

Contextualizing stories to their moment in the history of science is more difficult than placing them within political and social history. We don’t all take mandatory science history classes in school. Yet important scientific discoveries have a major impact on culture, from Cold War nuclear anxiety to the neon-drenched cyberpunk of the early computer era. And in the 19th and early 20th centuries, one of the biggest unanswered scientific questions was: How does the sun work?

During the Age of Enlightenment (yes, we really are starting that far back), as the scientific method replaced religion as the explanation for physical phenomena, the predominant scientific belief was that the universe and the bodies within it were endless. If God didn’t create the universe 6000 years ago, maybe it had simply always existed. Observationally, the sun has always been there throughout human history and it’s just as bright today as it was yesterday, so it’s logical to conclude that it will always be there. This basic belief in the static nature of the universe proved to be a hurdle for many scientific discoveries—for instance, one of the reasons the theory of evolution took time to be accepted was that extinction was not a widely-accepted phenomenon.

Science fiction was not yet a codified genre in this era, and few other than theologians were pondering the eventual fate of the earth. Yet there were premonitions. In 1815, Mount Tambora exploded in the most powerful volcanic eruption in recorded history. The resultant ash darkened skies around the world and plunged the planet into a cold spell dubbed The Year Without a Summer.

In the midst of this, Lord Byron wrote his 1816 poem Darkness, envisioning a world where the sun never returned:

The bright sun was extinguish’d, and the stars

Did wander darkling in the eternal space,

Rayless, and pathless, and the icy earth

Swung blind and blackening in the moonless air…

The waves were dead; the tides were in their grave,

The moon, their mistress, had expir’d before;

The winds were wither’d in the stagnant air,

And the clouds perish’d; Darkness had no need

Of aid from them—She was the Universe.

Byron’s primary focus was the human drama of these final days, and he drew primarily from imagination, not scientific theory. Yet his vision of a frozen, sunless earth foreshadowed later discoveries with remarkable prescience.

The codifying of the laws of thermodynamics in the mid-19th century prompted a major reevaluation of scientists’ assumptions about the universe. The first law of thermodynamics stated that energy had to come from somewhere. The second stated that it had to eventually run out.

Outside of fundamentalist Christian circles, most natural laws don’t inspire strong emotional reactions beyond interest and curiosity. But there’s a certain ennui to the second law of thermodynamics. While the billiard-hall laws of Newtonian mechanics run just as happily in reverse, entropy does not. It leaks out from every system, every interaction, always larger than before. What is broken can never be truly mended, it reminds us. What is lost can never be truly regained. Your every action, however mindful, is one more step on the inevitable journey to the heat-death of the universe.

The sun could no longer simply be an infinite energy source in the sky. The  magnificent beacon’s energy had to be finite, and it had to be caused by something. But what? Such a vast amount of power was a major challenge to the 19th-century model of physics.

The first explanation was offered by Robert Mayer in 1848, and again by Lord Kelvin a few years later: The sun is glowing because meteors are constantly crashing into it. This theory raised immediate and obvious problems. Where are all these meteors coming from? Why can’t we see them? How are we not all dead, since the meteors would presumably be raining their fiery fury on the earth at the same rate? “No doubt meteors fall into the sun, as assumed by Mayer and Thomson [Kelvin],” wrote Florian Cajori for Scientific American in 1908, “but the Mayer-Thomson theory made demands upon these meteors that bordered on extravagance.”

The first tenable explanation arrived in 1854 by Herman von Helmholtz: Gravitational contraction. As the heavy sun collapses under its own weight, the immense heat and pressure cause it to incandesce. Mathematically, this works. Stars are blackbodies, a type of material that’s black when cool and glows different colors when heated in a predictable sequence: Red, orange, yellow, white, and at its hottest, blue (iron being forged is a familiar example, though it never gets hot enough to glow blue). This suggested a very simple stellar life cycle: Hot, blue-white stars must be the youngest, gradually cooling to yellow, then red, before ceasing to glow altogether.

Moreover, unlike the mystery meteors, this theory is finite and quantifiable. Eventually, the sun would finish collapsing, the heat would dissipate, and it would slowly cool and darken into an inert lump of…stuff. (They were still hazy on that point; as late as the 1920s Arthur Eddington would be using models that assumed stars were almost entirely iron.) Knowing its mass, they could calculate how fast this would happen. So for the first time, it was possible to estimate the lifetime of the sun.

And the number was not large.

Initial estimates put the sun’s lifespan at around 20 million years. It could hardly be much younger than that, so its lifetime appeared to be mostly over. Soon it would burn out. What about the earth? It would freeze over, its orbit would decay, and it would draw closer to the husk of the sun, becoming tidally locked. Ultimately, it would fall into the remains of the sun and be destroyed, but not until long after all life went extinct. Humanity had, perhaps, a couple million years left before the sky darkened and the earth succumbed to eternal winter. Not a cheery thought.

Of course, a million years is hardly an imminent deadline on a human timescale—it’s still a hundred times the duration of all human civilization to date—but nevertheless, the idea that our world’s time was mostly up cast a bit of a pall.

Smack in the middle of these discussions, the natural world provided a most vivid illustration. In 1883, Krakatoa erupted nearly as violently as Tambora, ushering in another volcanic winter. (The 1800s were not a good century for volcanoes. Unless you were a geologist.) For the scientifically-minded, it must have felt like a premonition of earth’s eventual fate.

And yet the gravitation theory didn’t add up. For one thing, there was geology. While astrophysicists examined the sun, geologists were estimating the age of the earth based on its internal temperature, and their research dated the earth to some hundreds of millions or billions of years old. Biologists studying fossils estimated a similar age. Everyone agreed that the sun had to be older than the earth, so where did the discrepancy lie? “Lord Kelvin,” quoth Eddington in 1920, “…made strenuous efforts to induce geologists and biologists to accommodate their demands to this time-scale. I do not think they proved altogether tractable.”

For another thing, if the light came from incandescence, what on earth was a variable star? Surely a star couldn’t be alternately collapsing and un-collapsing.

Still, gravitation was the best anyone had, and this theory was taught to students for a solid seventy years. Among these students were the early luminaries of science fiction. The image of the earth’s long, slow descent into an endless ice age lodged itself firmly into their voracious minds, to percolate out in their works. Sometimes this was subconscious, in the form of the melancholic speculative fiction that dominated the genre’s early years. Other times, the sun’s imminent demise and its effect on humanity are the subject of the story itself: The dying-earth genre, which peaked in the first decades of the 20th century.

The most well-known example is The Time Machine by H.G. Wells (1895). In one of the book’s most memorable scenes, in a frenzied struggle to escape the Morlocks, the Time Traveler accidentally sends his machine forward in time instead of back and briefly journeys to the end of the Earth. The scene that greets him is a dismal one:

The sky was no longer blue. North-eastward it was inky black, and out of the blackness shone brightly and steadily the pale white stars. Overhead it was a deep Indian red and starless, and south-eastward it grew brighter to a glowing scarlet where, cut by the horizon, lay the huge hull of the sun, red and motionless…There were no breakers and no waves, for not a breath of wind was stirring. Only a slight oily swell rose and fell like a gentle breathing, and showed that the eternal sea was still moving and living…

I cannot convey the sense of abominable desolation that hung over the world. The red eastern sky, the northward blackness, the salt Dead Sea, the stony beach crawling with these foul, slow-stirring monsters, the uniform poisonous-looking green of the lichenous plants, the thin air that hurts one’s lungs: all contributed to an appalling effect…

All the sounds of man, the bleating of sheep, the cries of birds, the hum of insects, the stir that makes the background of our lives—all that was over.

The bright red sky evokes the dramatic volcanic sunsets following Krakatoa, which, twelve years later, must have still been a vivid memory. The still, lifeless sea recalls Byron.

But of particular note is the large, motionless red sun. The description resembles a red giant, and other than the cold temperature it would be easy to mistake this for modern astrophysics, where growing into a red giant marks the end of the sun’s life. In fact, Wells is depicting something completely different: The earth growing much closer to the sun due to orbital decay. Tidally locked, it no longer has day and night, but exists in a perpetual twilight with the sun fixed in a single place. The sun is larger because it’s closer; it’s red because it’s a cooling blackbody. The image of the large, red, cold, stationary sun would appear over and over in melancholic science fiction.

But horror author/sailor/bodybuilder William Hope Hodgson proved to be the champion of the dying-earth genre. Hodgson (who was an impressionable six-year-old at the time of Krakatoa) returned to this well twice at length. The first was his slightly brilliant, entirely delirious 1908 novel The House on the Borderland. In its extended flash-forward sequence, he flexes his understanding of the scientific theory of the day, describing the sun as:

…a tremendous globe of a glowing copper-bronze hue; in parts ringed with blood-red bands; in others, with the dusky ones, that I have already mentioned…these markings were due, probably, to differences in temperature of the various areas; the red representing those parts where the heat was still fervent, and the black those portions which were already comparatively cool.

In a moment of drama, the sun devours Mercury:

All at once, during one of these periods of life, a sudden flame cut across the night—a quick glare that lit up the dead earth, shortly; giving me a glimpse of its flat lonesomeness. The light appeared to come from the sun—shooting out from somewhere near its center, diagonally. A moment, I gazed, startled. Then the leaping flame sank, and the gloom fell again. But now it was not so dark; and the sun was belted by a thin line of vivid, white light. I stared, intently. Had a volcano broken out on the sun? Yet, I negatived the thought, as soon as formed. I felt that the light had been far too intensely white, and large, for such a cause.

Another idea there was, that suggested itself to me. It was, that one of the inner planets had fallen into the sun—becoming incandescent, under that impact…

After that one burst of flame, the light had shown, only as an encircling band of bright fire. Now, however, as I watched, it began slowly to sink into a ruddy tint, and, later, to a dark, copper-red color; much as the sun had done. Presently, it sank to a deeper hue; and, in a still further space of time, it began to fluctuate; having periods of glowing, and anon, dying. Thus, after a great while, it disappeared.

Long before this, the smoldering edge of the sun had deadened into blackness. And so, in that supremely future time, the world, dark and intensely silent, rode on its gloomy orbit around the ponderous mass of the dead sun.

Hodgson’s second foray into the death of the earth comes from his magnum opus, The Night Land (1912), a 600-page slog so notoriously impenetrable that even H.P. Lovecraft criticized its “painful verboseness.” The novel is set millions of years in the future, when the sun has long since burned out and the earth is a frozen wasteland inhabited by monsters. The last few million humans all live in one giant, technologically advanced pyramid, remembering the death of the sun only as a legendary creation story.

Hodgson’s depictions contain fanciful embellishments, but they are also peppered with meticulous scientific detail. In The House on the Borderland, carbon dioxide precipitates out of the atmosphere and falls as snow, and in the absence of an atmosphere, all sound becomes inaudible. In The Night Land, the earth’s crust has cracked as it cooled, creating fissures hundreds of miles deep. In one of the book’s most melancholic moments, the protagonist finds a book predicting that humanity’s remnants might relocate from the frozen surface to the bottom of these fissures, where it was still warm—only to realize that the icy wasteland he inhabits is the bottom of the fissure, that humanity made the journey thousands of years ago, and that there is no deeper refuge to flee to.

But while Wells and Hodgson were writing, science was progressing. In 1898, an upstart named Marie Curie showed up with some glowing rocks and upended everything.

Radium gave off impossibly vast amounts of energy seemingly out of nowhere, in defiance of all known physical laws. Atomic theory, mechanics, astrophysics—all had to rethink their fundamental assumptions in a true scientific revolution. There had to be another source of energy, enormous in magnitude, locked within the atoms themselves.

Nuclear energy.

Nuclear science opened up intriguing new possibilities to explain the sun. What if it was radiating energy from radioactive isotopes? No more was the sun on the brink of death—radium could fuel the sun for billions of years. And the problem of the sun’s age suddenly dissipated like polonium in a test tube.

“The sun is full of radium” may sound like an outlandish theory, but it was more sensible than it seems: scientists knew the sun contained helium (that is, in fact, where helium gets its name), and at the time, the only known source of helium was the radioactive decay of radium.

Gravitation did not go down without a fight. Lord Kelvin adamantly defended it against a battalion of younger scientists, including George Darwin (son of That Other Darwin), who Cajori quotes saying, “I think we have no right to assume that the sun is incapable of liberating atomic energy to a degree at least comparable with that which it would do if made of radium.” Despite the evidence against it, the gravitation theory would shamble on for another couple of decades, says Eddington, “not alive, but an unburied corpse.”

As it happens, the radium theory wasn’t correct either. It took another couple of decades before Arthur Eddington, in the same 1920 article quoted above, spitballed the theory which ultimately turned out to be correct: “The atoms of all elements are built of hydrogen atoms bound together…wherever it did occur a great amount of energy must have been set free; in a star a vast quantity of energy is being set free which is hitherto unaccounted for. You may draw a conclusion if you like.” In other words, nuclear fusion.

Like the radium theory, fusion allowed for a sun that might be billions of years old. These theories offered only a reprieve, but did not alter the ultimate sentence. Regardless of its power source, the sun would eventually run out of fuel, cool off, and go dark. All life on earth would die.

These new theories took the “we’re-all-about-to-die” urgency out of the death of the sun, and the dying-earth genre began to lose popularity. Yet the image of the dying sun was still a poignant one. Several sci-fi authors were drawn to the topic in this era, armed with the new scientific knowledge.

Now-disgraced sci-fi patriarch John W. Campbell tackled the dying earth in his short story “Night” (1935, published under the pseudonym Don A. Stuart). An experimental device accidentally transports a pilot to the end of the universe. He is met with an earth long since frozen, its automated machinery broken down long after all humans had perished:

There were frozen, huddled heaps that might once have been men. Little fellows with fear forever frozen on their faces huddled helplessly over something that must once have been a heating device. Dead perhaps, since the last storm old Earth had known, tens of billions of years ago…

Again I saw that agonizing struggle of the eternally faithful machines trying to repair themselves once more to serve their masters who were dead a million million years. I could see it again in the frozen, exhausted postures of the repair machines, stilled forever in their hopeless endeavors, the last poor dregs of energy spilled in fruitless conflict with time.

Campbell was well-versed in the latest science. “From hydrogen,” he says, “the heaviest of elements can be built up, and energy released,” but the stars “had burned their hydrogen until it was a remnant so small the action could not go on.” And this future is not a few millions of years off, but “billions on billions of years,” when not only the sun, but all the stars have burned out. 

And yet the imagery of the sun remains familiar:

It was four times—six times—the size of the Sun I knew. And it wasn’t setting. It was forty-five degrees from the horizon. It was red. Blood-red. And there wasn’t the slightest bit of radiant heat reaching my face from it. That Sun was cold.

(Note, however, that Wells’s vivid red sunset is not present. Campbell, born in 1910, did not experience Krakatoa.)

Astrophysics can show up in the smallest of traces. Did I mention Lovecraft? In The Shadow out of Time (1936), he briefly mentions the Yith’s future fate:

Later, as the earth’s span closed, the transferred minds would again migrate through time and space—to another stopping-place in the bodies of the bulbous vegetable entities of Mercury. But there would be races after them, clinging pathetically to the cold planet and burrowing to its horror-filled core, before the utter end.

The Yith moving inward in the solar system, not outward, indicates that Lovecraft, like his contemporaries, believed the sun would cool.

The modern stellar life cycle took several more years to work out. Red giants were the sticking point. Discovered at the turn of the century, they simply didn’t fit into any of the models. A first guess, during the era of the gravitation theory, suggested that they were young stars. Instead of hottest to coldest, the stellar life cycle moved from largest to smallest. A star began life as a red giant, and then gravitational contraction shrank it into a sunlike star, then a red dwarf. When that didn’t hold up, most astronomers concluded that red giants were their own thing.

The idea that red giants were in fact very old stars was first tenuously proposed in 1933, but only seriously considered in 1939. In the years that followed, a series of increasingly sophisticated models made it clear that red giants were a late stage of stellar evolution. Instead of gradually burning out, the sun would inflate into a flaming behemoth. The earth would not “go gently into that good night,” but would be devoured by this ball of fire.

The idea of being incinerated by the sun is not exactly a delightful one, but it’s significantly less angsty than the image of the lifeless, cold earth floating for eternity in the black void. Perhaps it’s simply that it’s a quicker end. Or perhaps it’s the part where the red giant collapses, spewing its gasses out across the galaxy to become the next generation of stars. Star stuff we are, and to star stuff we shall return.

The image of the earth being devoured by the sun is not without a certain drama of its own, and it makes an occasional appearance in sci-fi to this day. “The Dream with no Dreamer” by Evan Forman (2023) eloquently envisions this end:

After the cities had been put down and the planet flayed of life, the pyramids and pharaoh’s tombs were melted down to slag beneath the light of an expanding star. Then the buried dead were cremated in liquifying soil, the mountains tucked away into its volcanic folds.

Overall, though, this end just doesn’t have the same narrative potential, and certainly nowhere near the same urgency. Thus, the discovery of the modern stellar life cycle heralded the end of the melancholic depictions of the dying earth. Meanwhile, science fiction at large had evolved from Victorian pessimism to the techno-optimism of the pulp era. The dying-earth genre didn’t vanish on the spot, but it transformed into a stock setting for sword-and-sorcery stories set in the far future where modern civilization’s technology has long since been lost, beginning with Clark Ashton Smith’s Zothique stories, and the scientific underpinnings gradually dwindled away. You can see the modern descendants of these stories in the likes of Horizon Zero Dawn.

Yet the dying-earth imagery would linger in the minds of a generation of writers who had grown up with it, occasionally percolating to the surface outside of science fiction, in genres that had no reason to be bound by scientific accuracy. In The Magician’s Nephew (1955), C.S. Lewis references the image of the burned-out sun to depict the dying world of Charn:

“Was it the Deplorable Word that made your sun like that?” asked Digory.

“Like what?” said Jadis.

“So big, so red, and so cold.”

“It has always been so,” said Jadis. “At least, for hundreds of thousands of years. Have you a different sort of sun in your world?”

It wasn’t only sci-fi authors who found literary inspiration in the image of the dying sun. In fact, one of the genres most profoundly affected was poetry. Many prominent poets were deeply interested in the natural world and studied astronomy, and they too were influenced by the melancholia of the dying-earth era.

T.S. Eliot was an admirer of Arthur Eddington and kept up on his discoveries. Sometimes this knowledge of astronomy surfaces in his works with great clarity. “The Hollow Men” (1925) is one of Eliot’s darkest works. Written (by his own admission) during a severe bout of depression, the scarecrow-like titular hollow men whisper meaninglessly to each other in a “valley of dying stars” that bears striking resemblance to the dying-earth stories:

This is the dead land

This is cactus land

Here the stone images

Are raised, here they receive

The supplication of a dead man’s hand

Under the twinkle of a fading star.

Cosmic death saturates the poem. The wind is described as “More distant and more solemn/Than a fading star.” “Death’s twilight kingdom” makes several appearances—but is it the underworld or is it a description of earth in its final days, “This last meeting place” where the hollow men hopelessly gather, awaiting an inevitable death like the frozen men from “Night”?

The poem ends with the most famous lines of T.S. Eliot’s oeuvre:

This is the way the world ends

This is the way the world ends

This is the way the world ends

Not with a bang but a whimper.

The “bang” here is the Apocalypse that marks the end of the earth in traditional Christian theology (not, as one might guess, a supernova). In the depths of depression, Eliot rejects the church’s image of a fiery doomsday, finding more to relate to in the painfully slow, cold death offered by science.

Nor was he the only poet to observe the dichotomy between the cold death presented by science and the hot death presented by religion. But first, a story. There is an oft-repeated anecdote that, in 1920, Robert Frost asked astronomer Harlow Shapley how the world would end, and Shapley told him that it would either be incinerated by the sun, or somehow escape and slowly freeze—and was blindsided a few months later when a reference to this conversation appeared in a poem.

You should find this story immediately suspect. Neither Shapley nor anyone else in 1920 had any reason to think the sun would destroy the earth. And the provenance of the story doesn’t inspire confidence: Frost commentator Tom Hansen claimed in 2000 that Shapley had related the story in a talk in 1960. The meteor theory had more compelling evidence than this. So, unfortunately, we’ve got to mark this one as an urban legend.

But Frost did enjoy astronomy, and it makes an appearance in many of his poems. In “The Star-Splitter” (1923), a farmer buys a telescope “To satisfy a lifelong curiosity/About our place among the infinities.” And he kept up with the latest discoveries. “Skeptic” (1947), for instance, references Edwin Hubble’s discovery of redshift (while simultaneously expressing doubt about it:

I don’t believe what makes you red in the face

Is after explosion going away so fast.

So while Shapley may never have spoken to frost, we have every reason to believe that Frost had theories of the death of the sun in mind when he wrote his 1920 poem “Fire and Ice”. You already know the poem—some of you, no doubt, by heart—but I’m including it here anyways:

Some say the world will end in fire,

Some say in ice.

From what I’ve tasted of desire

I hold with those who favor fire.

But if it had to perish twice,

I think I know enough of hate

To say that for destruction ice

Is also great

And would suffice.

The poem’s metaphorical message is so resonant that it’s easy to overlook its literal meaning. Scientists at the time really did believe the world would end in ice, disagreeing with theologians, who claimed it would end in fire. For Frost, this disagreement about the physical world created an analogy for the different forms of human cruelty.

And so our journey takes us from the roots of science fiction to perhaps the most famous poem of the 20th century. It’s a cosmic microcosm of the creative arts’ relationship to all science: Curiosity and inspiration mingled with doubt and pessimism, the love of discovery colliding with the fear that we might wish we had never found out.

For while the dying-earth genre came to an end in the 1940s, physics was not done inspiring nihilistic visions of the future. I leave you with one final prescient quote from Arthur Eddington: “If, indeed, the sub-atomic energy in the stars is being freely used to maintain their great furnaces, it seems to bring a little nearer to fulfilment our dream of controlling this latent power for the well-being of the human race—or for its suicide.” 

Gwen C. Katz is the lead developer and wolfmaster of Nightwell Games, as well as an author, artist, and former mad scientist. She lives in Pasadena, California with her husband and a revolving door of transient animals. Her upcoming game, Surradia, is a deduction game that unravels the disappearance of three magical artists in interbellum France. You can visit her game studio at


Photo by Chris Barbalis.