10 Worlds Where Light Barely Exists

Added: 2026-06-02

[00:00:00]All right, let's go. Number 10, TrES-2b, the planet darker than coal. In the vast catalog of exoplanets discovered by our space telescopes, scientists expect to find worlds of dazzling variety. We have found planets covered in glittering oceans, worlds wrapped in swirling colorful storms of gas, and even planets that might be encrusted in diamond. But in 2011, astronomers analyzing data from NASA's Kepler space telescope identified something that defied all expectations.

[00:00:29]Located roughly 750 light-years away in the constellation of Draco, the gas giant designated TrES-2b is the darkest planet ever discovered in the known universe. To understand just how dark this world is, we have to look at a measurement called geometric albedo, which represents how much light a celestial body reflects. Earth reflects about 30% of the sunlight that hits it, making it a brilliant blue marble against the void. Jupiter, with its highly reflective ammonia clouds, reflects more than 50%. TrES-2b reflects less than 1% of the light from its host star. It is literally darker than black acrylic paint, darker than soot, and darker than a lump of coal. If you could somehow stand on a spacecraft approaching this world, you would not see a majestic sphere. You would see a massive, terrifying hole in the star field, a silhouette that actively devours the light around it. The mystery of why TrES-2b is so incredibly dark continues to puzzle astrophysicists. The planet orbits its star at an exceptionally close distance, completing a year in just 2 and 1/2 Earth days.

[00:01:35]Because it is so close, its atmosphere is heated to a staggering 980° C. At these extreme temperatures, the planet lacks the reflective clouds of ammonia or water ice that brighten our own solar system's gas giants. Instead, researchers hypothesize that its atmosphere contains highly light-absorbing chemicals, such as vaporized sodium, potassium, and gaseous titanium oxide. However, even these chemical models cannot fully explain the absolute void-like darkness of the planet. There is something else in the atmosphere of TrES-2b, an unknown chemical component or atmospheric dynamic that consumes light with almost perfect efficiency. What makes this world truly unsettling is a haunting visual detail. Because the planet is heated to nearly a thousand degrees, it is not perfectly invisibly black. Much like an electric heating coil on a stove that glows in the dark, TrES-2b emits a faint deep red glow from its own extreme thermal energy. It is a world wrapped in an atmosphere of suffocating darkness, radiating an eerie blood-red light into the vacuum of space, serving as a grim reminder that the universe can create environments that are fundamentally hostile to the very concept of illumination. Number nine, PSO J318.522, the wandering rogue. When we think of planets, we naturally picture them in orbit around a star, bathed in the life-giving warmth and light of a central sun.

[00:03:03]But the universe is a chaotic and violent place, and not all planets get to stay home.

[00:03:08]In 2013, astronomers using the Pan-STARRS telescope facility in Hawaii discovered an object designated PSO J318-522.

[00:03:19]Located about 80 light-years away from Earth, this is a rogue planet, a massive free-floating world that belongs to no star system. It drifts completely alone through the freezing, lightless void of the interstellar medium.

[00:03:33]With a mass roughly six times that of Jupiter, this solitary giant was likely born in a normal solar system, forming from a protoplanetary disk alongside sibling planets. But early in its system's history, a catastrophic gravitational interaction, perhaps a close encounter with a massive sibling or a passing star acted as a cosmic slingshot, violently ejecting it from its gravitational family and casting it out into the deep cosmic ocean.

[00:04:01]The reality of existing on a rogue planet is a master class in absolute darkness and isolation.

[00:04:07]On Earth, our entire concept of time, biology, and civilization is governed by the rising and setting of the sun.

[00:04:15]On PSO J318-5-22, there is no morning, no noon, and no dusk. There are no seasons, no years, and no climate cycles driven by solar radiation.

[00:04:29]If you were floating in the upper atmosphere of this world, the sky would be completely black punctuated only by the distant cold pinpricks of background stars.

[00:04:38]Because there is no host star to scatter light through its atmosphere, the sky would never turn blue, red, or purple.

[00:04:45]It is a state of perpetual unbroken midnight that will last for billions of years. Yet, paradoxically, this world is not completely frozen.

[00:04:55]The planet was discovered precisely because it emits a faint infrared glow.

[00:05:00]It is a relatively young object estimated to be only 12 million years old, and it still retains a massive amount of residual heat from its violent formation. Deep within its crushing interior, temperatures are hot enough to melt iron, and its atmosphere is a swirling storm of molten dust and liquid clouds.

[00:05:19]This presents a fascinating and deeply unsettling scenario for the search for life.

[00:05:24]Theoretical astrophysicists have proposed that some rocky rogue planets could maintain vast global oceans of liquid water trapped beneath miles of thick surface ice, kept warm entirely by the planet's internal geothermal heat.

[00:05:39]If life ever evolved in such an environment, it would exist in an ecosystem utterly divorced from starlight, a biological community thriving in the pitch black depths of a wandering world, completely unaware that the rest of the universe even exists as it drifts silently through the cosmic dark. Number eight, Sedna, the edge of our abyss.

[00:06:01]We do not need to travel to distant star systems to find worlds where light struggles to exist. We simply need to look at the extreme edges of our own solar system. Beyond the orbit of Neptune, beyond the familiar icy realm of the Kuiper Belt, lies a region of space so distant and so cold that the sun itself loses its status as a life-giving celestial body and becomes little more than a brilliant mocking star.

[00:06:26]Here, in the scattered disc, astronomers discovered Sedna in 2003.

[00:06:31]Sedna is a dwarf planet roughly the size of the asteroid Ceres, but what makes it profoundly disturbing is its orbit.

[00:06:38]While Earth completes an orbit around the sun in 1 year, Sedna takes a staggering 11,400 years to complete a single journey.

[00:06:46]Sedna's orbit is highly elliptical, carrying it away from the sun into the true darkness of deep space. At its closest point, or perihelion, Sedna is 76 astronomical units away, which is more than twice the distance from the sun to Neptune. But at its farthest point, its aphelion, Sedna travels an incomprehensible 937 astronomical units away from the sun.

[00:07:09]At this extreme distance, the environment is defined by sensory deprivation. If you were standing on the surface of Sedna at aphelion, the sun would not look like a disc in the sky.

[00:07:19]It would be reduced to a single intensely bright point of light, indistinguishable in size from the other stars, offering absolutely no perceptible heat and casting shadows so faint they would be almost impossible to see with the human eye.

[00:07:33]The surface temperature drops to nearly minus 240° C, a cold so absolute that the atmosphere itself freezes solid, falling to the ground as a layer of nitrogen and methane snow.

[00:07:45]What makes Sedna even more eerie is its appearance. Despite the almost total lack of sunlight, Sedna is one of the reddest objects in the entire solar system, rivaling the color of Mars. This deep blood-red coloration is the result of tholins, complex organic molecules that form when the scant ultraviolet light from distant stars and the sun interacts with simple organic compounds like methane over millions of years.

[00:08:12]This world is a frozen red tomb locked in a state of near absolute darkness.

[00:08:18]Its discovery forced astronomers to ask a chilling question. Sedna should not be there.

[00:08:24]The current architecture of the solar system cannot easily explain how a planetoid was pulled into such a massive detached orbit. Many astrophysicists believe Sedna's orbit is the gravitational scar left behind by an unseen ghost, perhaps a passing star from the sun's birth cluster billions of years ago, or the hypothetical planet nine, a massive unseen world lurking even deeper in the dark, pulling strings in the absolute blackness at the edge of our home system. Number seven, Upsilon Andromedae b, the eternal night.

[00:08:57]When we search for lightless environments, we often think of places incredibly distant from any star.

[00:09:02]But one of the darkest, most terrifying environments in the cosmos exists directly adjacent to a raging inferno.

[00:09:09]In 1996, astronomers discovered Upsilon Andromedae b, a massive gas giant orbiting a star about 44 light-years away from Earth.

[00:09:19]This planet is a hot Jupiter, meaning it is a massive world located incredibly close to its host star.

[00:09:25]It orbits at a distance of just 0.05 astronomical units, whipping around its star in just 4.6 Earth days.

[00:09:34]Because it is so close, the gravitational interaction between the planet and the star has forced the planet into a state of tidal locking.

[00:09:42]Tidal locking means the planet's rotation has perfectly synchronized with its orbit, resulting in a world with two distinct permanent hemispheres.

[00:09:50]One side of the planet constantly faces the star, enduring perpetual blinding daylight and temperatures that can melt rock. But the other side of the planet never sees the sun. It faces outward, staring eternally into the cold, empty expanse of the cosmos.

[00:10:07]This is the eternal night side, a realm where starlight never reaches and true morning will never come.

[00:10:13]The contrast between these two hemispheres creates an atmospheric nightmare.

[00:10:17]Data from the Spitzer Space Telescope revealed an astonishing temperature difference of roughly 1,400° C between the day side and the night side.

[00:10:28]This extreme thermal gradient drives winds of incomprehensible power.

[00:10:32]Supersonic storms roar across the twilight zone, carrying superheated gas from the day side into the freezing darkness of the night side.

[00:10:41]As this vaporized material crosses the terminator line and plunges into the dark, it rapidly cools and condenses.

[00:10:49]Scientists theorize that on the night side of Upsilon Andromedae b, the pitch-black sky is filled with clouds made of silicates, essentially vaporized rock, and it rains molten iron or liquid glass in the absolute darkness.

[00:11:03]The horror of this world is one of duality. If you were somehow suspended in the atmosphere of the night side, you would be surrounded by freezing darkness and violently howling winds, completely cut off from the light of the star just thousands of miles beneath your feet.

[00:11:19]It is an environment of supreme sensory deprivation, existing right next door to absolute sensory overload. A dark, churning abyss forever tethered to a blinding sun it can never look at.

[00:11:31]Number six, WISE 0855-0714, the freezing sub-brown dwarf.

[00:11:39]In 2014, astronomer Kevin Luhman was examining data from NASA's Wide-field Infrared Survey Explorer when he found something lurking incredibly close to our solar system.

[00:11:51]Just 7.2 light-years away, making it the fourth closest star system to our sun, sits an object designated WISE 0855-0714.

[00:12:02]The reason it took us so long to find something literally in our cosmic backyard is because this object emits absolutely no visible light. It is not a star, and it is barely even a brown dwarf. It falls into a highly exotic category known as a sub-brown dwarf or a free-floating planetary mass object. It is a failed star so small and so incredibly cold that it blurs the line between a planet and a star.

[00:12:28]To understand the darkness of this system, we have to look at its temperature. Traditional brown dwarfs are cool, but they still retain enough heat to glow a dull magenta or deep red.

[00:12:38]WISE 0855, however, has a temperature ranging from -48°C to -13°C. It is colder than a winter day at the North Pole.

[00:12:48]At these freezing temperatures, the object is completely dark in the visible spectrum. The only way we can detect it is through its incredibly faint thermal emissions in the infrared.

[00:12:58]When astronomers studied the spectrum of this object, they found evidence of water ice clouds in its atmosphere, making it the first object outside our solar system to have confirmed water clouds.

[00:13:08]Now, consider the terrifying implications if this sub-brown dwarf hosts its own system of moons, which is entirely possible given its mass of three to 10 times that of Jupiter.

[00:13:18]If you were standing on a rocky moon orbiting WISE 0855, the sky would be a canvas of absolute unfiltered black.

[00:13:26]Your primary celestial body, the massive gas giant dominating the sky, would be entirely invisible to the naked eye.

[00:13:33]You would only know it was there because it would block out the background stars as it passed in front of them. An enormous creeping void moving across the heavens.

[00:13:42]The only light would be the faint glow of distant stars. There would be no solar energy to drive photosynthesis, no warmth to melt surface ice, and no light to see your own hands in front of your face.

[00:13:53]It is a complete functioning celestial system existing entirely in the dark. A silent ghost system drifting through the interstellar neighborhood right next to our own. Reminding us that the majority of the universe's mass might be hiding in pure unilluminated darkness.

[00:14:09]Number five, Europa's hidden oceans, the lightless deep.

[00:14:14]When we search for life beyond Earth, we often look for the light. We look for the habitable zone where sunlight can keep water liquid on a planetary surface. But one of the most promising places for alien life in our solar system is a realm where sunlight has not penetrated for over 4 billion years.

[00:14:31]Europa, the fourth largest moon of Jupiter, presents a smooth icy surface to the cosmos, cracked and scarred by the immense gravitational tidal forces exerted by the gas giant.

[00:14:42]The surface of Europa is bathed in the dim light of the distant sun and subjected to lethal doses of Jupiter's radiation.

[00:14:49]However, beneath that frozen crust, which is estimated to be 15 to 25 km thick, lies ocean of liquid salt water.

[00:14:58]This subsurface ocean contains more than twice the amount of liquid water found in all of Earth's oceans combined.

[00:15:05]Because of the massive impenetrable ceiling of solid ice, the ocean of Europa exists in a state of absolute eternal pitch black. No photon from the sun has ever touched these waters. The environment is defined by crushing pressure and freezing temperatures near the ice boundary. Yet the water remains liquid because Jupiter's gravity constantly stretches and squeezes the moon's interior, generating immense internal friction and heat. This tidal heating is the heartbeat of Europa, and it drives what scientists believe is an active seafloor thousands of meters below the ice.

[00:15:38]If we look at Earth's own deep oceans, we find hydrothermal vents, massive chimneys on the seafloor spewing superheated mineral-rich water into the freezing depths.

[00:15:47]Around these vents, life thrives in the absolute darkness, relying not on photosynthesis from the sun, but on chemosynthesis, drawing energy directly from the chemical reactions of the Earth itself.

[00:15:59]It is highly probable that Europa's dark ocean floor hosts similar hydrothermal vent systems.

[00:16:04]If life exists in this alien ocean, it has evolved in a state of complete sensory deprivation regarding the outside universe.

[00:16:12]Any organism swimming through these lightless waters would have no concept of stars, planets, or the vast cosmos above their icy sky.

[00:16:20]Their entire reality would be a dark pressurized void, perhaps illuminated only by the faint ghostly glow of bioluminescence as organisms hunt and communicate in the deep, or the dull red glow of magma welling up from the fractured core.

[00:16:34]It is a staggering thought, an entire ancient biosphere existing in our own solar system, thriving in an environment of absolute darkness where the concept of light is practically nonexistent.

[00:16:46]Number four, PSR B1257+12, the Pulsar Shadow.

[00:16:52]The story of how humanity discovered the very first planets outside our solar system is not a tale of finding an Earth-like paradise orbiting a warm yellow sun.

[00:17:01]It is a story of discovering a nightmare system of zombie worlds orbiting the violent corpse of a dead star.

[00:17:07]In 1992, astronomers Alexander Wolszczan and Dale Frail announced the discovery of two, and later three, planets orbiting a pulsar designated PSRB 1257 + 12, located 2,300 light-years away in the constellation of Virgo.

[00:17:24]A pulsar is a rapidly rotating neutron star, the crushed hyper-dense core left behind after a massive star ends its life in a cataclysmic supernova explosion.

[00:17:35]This particular pulsar spins 161 times every single second, sweeping beams of intense, deadly electromagnetic radiation across the cosmos like a maddened, invisible lighthouse.

[00:17:47]The planets orbiting this dead star, named Draugr, Poltergeist, and Phobetor, are truly worlds where light, as we understand it, barely exists.

[00:17:57]The supernova explosion that created the pulsar would have utterly destroyed any original planets in the system.

[00:18:03]The worlds we see today are second-generation planets, formed from the heavy, irradiated debris and ash of the destroyed star system slowly coalescing over millions of years.

[00:18:14]Because the central star is dead, it does not emit the comforting visible light of a normal sun. It emits x-rays, gamma rays, and high-energy particles.

[00:18:24]If you were standing on the surface of Poltergeist, you would be standing on a barren landscape of heavy metals and radioactive rock.

[00:18:32]The sky above would be fundamentally dark, deprived of the warming glow of a host star.

[00:18:38]The only illumination would be the horrifying, silent auroras stretching across the thin, dead atmosphere triggered by the relentless bombardment of high-energy radiation from the spinning pulsar.

[00:18:50]The radiation environment is so intensely lethal that it would instantly sterilize any complex molecules, stripping away atmospheric gases and irradiating the ground.

[00:19:01]This is a system that exists in the literal shadow of death, a collection of planetary ghosts circling a stellar corpse in the dark. It challenges our understanding of planetary formation, proving that planets can form even in the most hostile, light-deprived, and violent environments imaginable, enduring an eternity of darkness punctuated only by the invisible, deadly pulses of a dead star's heartbeat.

[00:19:27]Number three, the Coalsack Nebula.

[00:19:30]Planets, the dust-choked worlds.

[00:19:33]When we look up at the night sky, we are accustomed to seeing the black void of space punctured by the brilliant light of countless stars. But, there are regions of the galaxy where the sky is broken not by light, but by absolute suffocating darkness. These are dark nebulas or Bok globules, immense interstellar clouds of cosmic dust and dense molecular gas that are so thick they completely absorb and block the visible light from the stars behind them.

[00:20:01]One of the most famous examples is the Coalsack Nebula, an enormous dark silhouette against the Milky Way, located about 600 light-years away from Earth.

[00:20:11]To the naked eye, it looks like a tear in the fabric of the galaxy, a void where stars seemingly refuse to exist.

[00:20:18]But, these dark nebulas are not empty voids. They are stellar nurseries. The dense concentration of dust and gas makes these regions incredibly massive and gravitationally unstable, leading to the collapse of material and the birth of new stars and planetary systems within the dark cloud.

[00:20:37]Now, consider the terrifying reality of a planet forming around a young star deep inside the core of the Coalsack Nebula.

[00:20:45]For billions of years, the environment of this planetary system would be uniquely isolated from the rest of the cosmos.

[00:20:52]The thick, localized concentration of interstellar dust would act as a cosmic curtain, absorbing practically all the light from the outside galaxy.

[00:21:02]If a civilization were to evolve on a planet deep within such a nebula, their perception of the universe would be fundamentally flawed. They would have a sun, but when night fell, their sky would not be filled with constellations, galaxies, or the glowing band of the Milky Way.

[00:21:18]Their night sky would be a ceiling of pure impenetrable blackness.

[00:21:23]The dust would choke out the light of the universe, plunging the night into absolute darkness.

[00:21:28]Without stars to guide them, early navigation across oceans would be nearly impossible.

[00:21:33]Without the light of distant galaxies, their astronomers might reasonably conclude that their solar system is the only thing that exists in the entire universe.

[00:21:42]They would be trapped in a cosmic isolation tank, a world where the concept of a vast, star-filled universe is an impossible fantasy. Their existence confined entirely within the suffocating, light-devouring walls of a nebula.

[00:21:55]It is an environment where the absence of background light fundamentally reshapes the reality and potential worldview of any life that might emerge there. Number two, blanets, the event horizon worlds.

[00:22:07]When we push the boundaries of theoretical astrophysics, we encounter concepts that sound like they belong in a horror novel rather than a scientific journal.

[00:22:16]In 2020, a team of researchers from Kagoshima University in Japan published a paper proposing the existence of a new class of celestial bodies, blanets or black hole planets.

[00:22:27]We know that supermassive black holes at the centers of galaxies are surrounded by massive accretion disks, swirling vortexes of superheated gas and dust spiraling toward the event horizon.

[00:22:39]The researchers proposed that at a specific distance from the black hole, outside the corona but within the disk, the environment cools down enough for dust to coalesce.

[00:22:49]In this snowline, thousands of light-years from the black hole's center, planets could form not around a star, but directly in orbit around a supermassive black hole.

[00:22:59]The environment of a blanet represents the ultimate extreme of cosmic darkness and terror.

[00:23:05]If the black hole is actively feeding, the accretion disk would bathe the planet in intense lethal radiation and highly distorted, heavily blue-shifted light.

[00:23:14]But if the black hole is dormant, lacking an active accretion disk, the reality becomes far more unsettling.

[00:23:21]The primary celestial body governing this world is not a radiant star, but an immense void, a tear in the fabric of space-time.

[00:23:30]If you were standing on a planet orbiting a dormant supermassive black hole, you would be looking up at a sky dominated by a massive sphere of absolute, perfect nothingness.

[00:23:40]Because black holes consume light, the sky would not just be dark, it would be physically warped. The extreme gravity of the black hole would act as a gravitational lens, bending and distorting the light of the background stars around its edges, creating a terrifying halo of smeared, warped starlight encircling a massive central shadow.

[00:24:00]There would be no warmth, no day or night cycle, only the eternal, silent orbit around an object that represents the literal end of physics.

[00:24:09]The mass of these theoretical planets could be up to 3,000 times that of Earth, making them gargantuan worlds of rock and ice, crushed under their own immense gravity, existing in the coldest, darkest, and most gravitationally violent environments in the known universe.

[00:24:26]It is a scenario that forces us to confront the reality that a planetary formation is not a gentle process tied only to stars, but a relentless consequence of gravity that can create worlds in the darkest, most hostile abysses of space-time.

[00:24:42]Number one, rogue planets in the Boötes void, absolute isolation.

[00:24:47]To find the ultimate world of darkness, we must combine the isolation of a rogue planet with the most terrifying geographical feature of the large-scale universe.

[00:24:57]In 1981, astronomers discovered the Boötes void, an almost perfectly spherical region of space roughly 330 million light-years in diameter.

[00:25:07]It is a cosmic desert of staggering proportions. While a region of space this massive should contain approximately 10,000 galaxies, astronomers have found fewer than 60. It is a pocket of emptiness so vast that if the Milky Way were placed in its center, humanity would not have known other galaxies existed until the invention of powerful telescopes in the 1960s.

[00:25:30]Now, imagine a rogue planet, a world ejected from its home star system, drifting not within a galaxy, but cast entirely out of its host galaxy into the intergalactic medium, and specifically, drifting into the dead center of the Boötes void.

[00:25:47]This theoretical world represents the absolute zenith of darkness and cosmic isolation.

[00:25:53]It is unbound from any star, so it has no sun. It is unbound from any galaxy, so it has no galactic plane of stars to illuminate its sky. It is drifting through a region of space where even other galaxies are separated by tens of millions of light-years of absolute nothingness.

[00:26:10]If you stood on the surface of this ultimate rogue planet, the sensory deprivation would be absolute and unrelenting. The sky would be perfect, mathematical black.

[00:26:21]The nearest photons of light from the scattered distant galaxies within the void would be so unimaginably faint that the human eye could not detect a single one.

[00:26:30]It is an environment of total, flawless darkness extending for hundreds of millions of light-years in every possible direction.

[00:26:38]The temperature would be fractions of a degree above absolute zero, just slightly warmer than the cosmic microwave background radiation itself.

[00:26:47]There would be no sound, no light, no stellar wind, and no gravitational influence from any neighboring star.

[00:26:54]It is a world suspended in an ocean of pure emptiness, a silent rock moving through a darkness so profound that it borders on nonexistence.

[00:27:04]It forces us to realize that the universe is not just filled with light and matter, but dominated by an incomprehensible void. And somewhere in that absolute dark, lost worlds are silently drifting through eternity.

[00:27:17]I'll be sharing more similar videos in the future, so subscribe to stay tuned.