Is 3I/ATLAS the Next ʻOumuamua? Here's What Scientists Know

[00:00:00]On July 1st, 2025, a telescope camera in the Atakama desert of Chile detected something moving through the constellation of Libra that did not belong to our solar system. The Atlas Survey Telescope, which is part of NASA's planetary defense network and spends its nights scanning the sky for objects that might pose a risk to Earth, captured a small faint point of light moving at a speed so high that the only explanation was that it had arrived from somewhere beyond the solar system entirely. Within 24 hours, astronomers at the Minor Planet Center had confirmed what the data was showing. The speed, the trajectory, the angle of approach.

[00:00:33]All of it pointed to the same conclusion. This visitor had not formed an orbit around our sun. It had not come from the Orort cloud, the distant reservoir of icy objects at the edge of our solar system. It had traveled from another star system entirely, moving at approximately 137,000 mph. and it was now falling inward toward the sun on a path that would take it through the heart of our solar system and out the other side before disappearing forever into the darkness between the stars.

[00:01:00]Scientists named it ThreeI Atlas, the third interstellar object ever detected by human civilization, named after the telescope that found it. And over the months that followed, as the most sophisticated array of space telescopes and groundbased observatories ever pointed at a single comet tracked its journey through our solar system, what the data revealed was something that made astronomers describe it as one of the most scientifically significant objects in the history of astronomy. I am your name and this is your channel.

[00:01:28]Subscribe right now if real science is what you come here for. We go this deep every week. Now, let us get into it. To understand why ThreeI atlas matters so much, you need to understand the full context of what it means to detect an object that came from outside our solar system. Our solar system is surrounded by an enormous and essentially empty gulf. The nearest star to our sun, Proxima Centuri, sits about 4.2 lighty years away. That is approximately 25 trillion miles of open space. For an object to cross that gulf and enter our solar system, it has to have been traveling through interstellar space for an enormous amount of time. And when it arrives here, the sun's gravity accelerates it to speeds that no object formed in our own solar system could naturally achieve. This is how astronomers first recognized each of the three interstellar visitors humanity has detected. Their speeds, when calculated against their positions and trajectories, were simply too high to be consistent with any object that originated here. They were not bound by the sun's gravity. They were passing through. The first time this happened in recorded history was in October 2017 when the Pan Stars telescope in Hawaii detected an object hurtling through the solar system at about 26 km/s relative to the sun. The object was named one eye umam Mua, a Hawaiian phrase meaning something like a messenger from afar arriving first. And from the moment it was identified as an interstellar visitor, it made almost no sense. It had no coma. When a comet approaches the sun, the heat causes ice on its surface to sublimate directly into gas. And that gas carries dust with it, forming the glowing halo called a coma, and the tail that makes comets one of the most beautiful and recognizable sites in the night sky. Mua showed none of this. No coma, no tail, no outgassing detected by any instrument. It looked more like a rocky asteroid than a comet. Its shape was bizarre, either extremely elongated like a cigar or unusually flat like a pancake, depending on which analysis of its brightness variations you trusted.

[00:03:23]And then it did something that nobody could immediately explain. It accelerated as it left the solar system.

[00:03:29]Not just from the sun's gravitational pull, which would produce a predictable, calculable trajectory. Something else was pushing it, adding velocity in a way that matched no known natural mechanism perfectly. The object was already on its way out of the solar system by the time it was discovered, and the observation window lasted only weeks before it disappeared from telescope range forever. The questions it left behind have never been definitively answered.

[00:03:52]The second interstellar visitor was less mysterious, but no less scientifically valuable. Two I Borisov was discovered on August 30th, 2019 by an amateur astronomer named Gennady Borisov in Crimea. And unlike Umwamua, it was unmistakably, beautifully, straightforwardly a comet. It had a coma. It had a tail. It produced the outgassing you would expect from an icy body heated by the sun. It behaved in all the ways a comet should behave. Its composition when analyzed by spectroscopy turned out to be remarkably similar to comets from our own solar system. Rich in water ice and carbon monoxide and the kinds of organic molecules that appear in comets from every direction we have looked. 2i Borisoft told us something reassuring that the basic chemistry of planet formation, the kinds of icy building blocks that come together to make a comet, appears to be similar across at least some part of the galaxy. It was an interstellar visitor that turned out to be in composition, if not in origin, quite familiar. And then three Atlas arrived and it was neither familiar nor simple. The Atlas telescope in Chile captured it on July 1st, 2025 at a distance of roughly 4.5 astronomical units from the sun, approximately the distance of Jupiter's orbit. That discovery data was immediately reported to the Minor Planet Center, and within days, pre-discovery images were found in archival data going back to May 7th, 2025, captured by the test satellite, which is normally used to search for planets orbiting other stars. Those archival images showed something remarkable. As early as May 7th, the object already had a coma. It was already active, already releasing gas and dust at a distance of more than 6.4 astronomical units from the sun. That is further from the sun than Saturn. For comparison, most comets from our own solar system only begin developing their comas as they get closer than about three astronomical units from the sun, roughly the distance of the asteroid belt. Three Atlas was releasing material at more than twice that distance.

[00:05:43]Something about the composition of its surface was so volatile that it began sublimating and outgassing even in the cold of the outer solar system far from the warming influence of the sun. This single fact told astronomers something important immediately. This object was not like umamu mua. This was unambiguously a comet. It had the coma, the tail, the outgassing, the spectral characteristics. And the data quickly revealed that it was extraordinarily rich in what astronomers call volatiles, substances that turn from solid to gas relatively easily. Over the following weeks, as more observations poured in from telescopes around the world, the picture of three Atlas became simultaneously clearer and more astonishing. The speed was the first number that stopped people. When three Atlas was discovered, it was moving at approximately 58 km/s relative to the sun. That is its hyperbolic excess velocity, the speed it would have in the absence of the sun's gravity, which is the true measure of how fast it was traveling through interstellar space before it entered our solar system. To put that in perspective, hyperbolic excess velocity was about 26 km/s.

[00:06:48]2i Boris was about 32 km/s. 3i Atlas at 58 km/s was nearly twice as fast as Umwamua and almost twice as fast as Boris. It is, as of the time this script was written, the fastest interstellar object ever detected. Pulled by the sun's gravity as it fell inward toward perihelion, it accelerated further to approximately 153,000 mph at its closest approach to the sun on October 29th, 2025. The size, when the Hubble Space Telescope turned its attention to the comet in August 2025, was estimated from the brightness of the nucleus at between 440 m and 5.6 km in diameter. That range is wide because the coma surrounding the nucleus makes it difficult to isolate the nucleus itself. But even the lower estimate of 440 m makes it a substantial object and the upper estimate of nearly 6 km would make it one of the larger comets ever studied in detail. For reference, the comet that most scientists believe struck Earth and contributed to the mass extinction that ended the dinosaurs was estimated to be roughly 10 to 15 km across. 3IIR Atlas, even at its most conservatively estimated size, is a significant body.

[00:07:58]The orbital parameters tell you everything about where it came from and where it is going. The eccentricity of 3II Atlas's orbit is approximately 6.1.

[00:08:07]An eccentricity of exactly one describes a parabolic orbit, the borderline between a bound and unbound trajectory.

[00:08:13]An eccentricity greater than one describes a hyperbolic orbit, meaning the object is not gravitationally bound to the sun and will escape after its closest approach. Most comets from our own solar system have eccentricities very close to one because they originate in the distant orort cloud and fall inward under the sun's gravity and paths that are nearly but not quite parabolic.

[00:08:32]Three I atlas at an eccentricity of 6.1 is the most dynamically extreme object ever recorded in the solar system. That number tells you not just that it is interstellar but that it arrived with an enormous amount of kinetic energy that the sun's gravity has only modestly influenced. The orbit is also retrograde, meaning it is traveling in the opposite direction to the planets in our solar system at an inclination of about 175° relative to the ecliptic plane. It came in from above and behind.

[00:09:01]Now, here is where the story becomes genuinely extraordinary and where the new research published in Nature in June 2026 delivers something that puts everything else in perspective. Analysis of three eye atlas's chemical composition. Particularly the ratio of heavy water to regular water in its outgassing produced a number that made astronomers pause. The dutarium to hydrogen ratio in water is a tracer of where and when a body formed. Water ice that forms in the very cold, very ancient environments of the outer galaxy tends to be enriched in dutyium, the heavier isotope of hydrogen compared to water that forms closer to a star or in warmer, younger environments. The dutarium to hydrogen ratio measured in 3i atlas was more than 30 times higher than the ratio found in comets from our own solar system. 30 times higher. This is not a small difference. It is an enormous compositional divergence that points to three atlas having formed in an extremely cold extremely old environment far from any star in the early history of the galaxy. combined with dynamical modeling of how long an object with its speed and trajectory would have been traveling through interstellar space. The researchers concluded that three eye atlas has been drifting through the galaxy for somewhere between 10 and 12 billion years. Our solar system itself is only about 4.6 billion years old. The universe is approximately 13.8 billion years old. This comet, this small icy body that passed through our solar system in 2025 and 2026, formed in the early universe, long before our sun existed, and has been traveling through the galaxy ever since. It is almost as old as the universe itself. This is not a metaphor. It is a physical object. It passed close enough to Earth for Hubble to photograph it. the James Webb Space Telescope, the European Space Ay's Juice mission, which was on route to Jupiter and observed the comet using its monitoring instruments, the Mars Reconnaissance Orbiter, which captured images of it from Mars orbit. And dozens of groundbased telescopes all studied this 10 to 12 billiony old object as it traveled through our neighborhood. We have spectra of its composition. We have measurements of its outgassing rates. We have images of its coma structure, which showed complex extended filaments and evidence of possible surface fragmentation as it heated near the sun.

[00:11:11]ESA's Juice spacecraft designed to study Jupiter's moons turned its instruments on three eye atlas during the approach phase and captured detailed observations of dustrich outflows from the inner coma. This is real data from a body that predates our solar system. Let us now address the question that generated the most public attention during three Atlas's passage through the solar system and that deserves a clear and honest answer. Could Three Atlas be an artificial object, a spacecraft from another civilization?

[00:11:40]Avi Lobe, a professor of astronomy at Harvard University, who first attracted wide attention with his 2021 hypothesis that Umamua might have been an artificial light sail, argued in several public statements about three-ey, that its trajectory was unusually precise, and that it could not be ruled out as an artificial object. He cited the specific geometry of its close approaches to multiple planets as statistically improbable for a randomly arriving natural object. His estimate was that the probability of a randomly arriving interstellar object having this particular trajectory was extremely low on the order of a fraction of a percent.

[00:12:14]The scientific community's response was clear and based on specific observations that Loe's framework did not account for. First, three Atlas has a well-developed coma and tail that are produced by outgassing from an icy nucleus. This is exactly what natural comets do when heated by the sun. No artificial spacecraft design that any engineer has proposed would waste mass by producing a kilometers wide coma of gas and dust as a byproduct of its approach to a star. Second, the DH ratio and spectroscopic composition of the coma are consistent with natural icy material of ancient origin, not with any kind of engineered propellant or material. Third, astronomers at the University of Regina and other institutions pointed out that the statistical argument about the trajectory depends on how you define what counts as a close approach and to which planets and that the trajectory of three atlas while geometrically interesting is not as improbable as Loe's framing suggested when you run the numbers properly. Samantha Lawler, an astronomer specializing in solar system dynamics, described it straightforwardly as an ordinary comet ejected from another star system, consistent with the billions of comets that are expected to be drifting through interstellar space at any given time based on our models of planet formation. The scientific consensus on threeey atlas is unambiguous. It is a comet, an ancient, remarkably primitive, scientifically extraordinary comet from the early universe, but a comet. The data supports no other conclusion and the data is extensive. At the same time, it is worth being precise about what Avi Loe's minority view represents in context. He has consistently argued that we should not rule out artificial explanations simply because they are uncomfortable and that the absence of confirmation is not the same as absence of possibility.

[00:13:55]On that narrow methodological point, most scientists would agree that extraordinary claims require extraordinary evidence and the evidence for threeey atlas being a natural object is substantial while the evidence for it being artificial is essentially none.

[00:14:09]That is where the scientific argument stands.

[00:14:12]Now, here is the first major twist in this story and it connects Threeey Atlas directly to a question about the history of life in the universe. The Umuam Mua encounter in 2017 and the threeey atlas encounter in 2025 were separated by eight years. In the roughly 50 years before 2017, astronomers detected zero interstellar objects passing through the solar system. Then in 8 years, three.

[00:14:35]This could be coincidence driven by improving survey technology. The same telescopes that found three eye atlas are far more sensitive than anything that existed in 2010 and they cover more sky more rapidly. It is genuinely likely that umwamua like objects have been passing through the solar system throughout history and were simply too small and too fast to detect before modern survey cameras existed. But the rate at which objects like these are being detected and the way that rate will only increase as survey technology continues to improve tells us something important about the galaxy we live in.

[00:15:05]Based on the observed rate of interstellar object detections and the detection limits of current telescopes, astronomers have estimated that there may be of order 10,000 such objects passing through the inter solar system at any given time. That the interstellar medium may contain an enormous population of small bodies, comets, asteroids, and other debris ejected from forming planetary systems across the galaxy throughout its history. 3II Atlas with its 10 to 12 billionyear age estimate is a survivor from the earliest era of planet formation in the galaxy.

[00:15:36]The building blocks of planets around ancient stars scattered outward by gravitational interactions with forming gas giants have been drifting through the galaxy ever since. We are occasionally catching one as it passes through. When we analyze that material and find that its chemistry is dramatically different from our own solar systems comets, we are learning something about chemistry in those ancient distant environments. Every interstellar object we detect and characterize is in a literal sense a sample return mission that the universe ran on our behalf. Here's the second major twist and it is one that connects everything about three Atlas to what happens next. In March 2026 after 3i Atlas had passed through its perihelion in late October 225, reached its closest approach to Earth on December 19th 2025 at a distance of approximately 168 million miles and swung around to head back outward. The comet made a close pass of Jupiter. On March 16th, 2026, it came within approximately 33 million miles of Jupiter, well within the gravitational influence zone, where the gas giant's enormous mass can measurably affect the trajectory of a passing object. Dynamical simulations published by researchers at the physical research laboratory in India confirmed that both the Mars encounter and the Jupiter encounter produced measurable gravitational perturbations to three eye atlases orbital elements. Jupiter, the most massive planet in our solar system, affected the trajectory of this ancient interstellar comet as it passed by. The comet that has been drifting through the galaxy for 10 billion years had its path slightly altered one final time before leaving our solar system forever. It is now heading back into interstellar space where it will continue traveling until something else deflects it or until the universe changes around it. The three-ey atlas encounter also accelerated a conversation that had been building in the interstellar science community for years. What would it take to send a mission to one of these objects and study it up close? Project Lyra, an initiative by the Institute for Interstellar Studies, proposed a mission to intercept Umuama after it was discovered. And the engineering analysis showed that it would be extremely challenging but potentially achievable using a trajectory that involved gravity assists from Venus, Earth, and Jupiter, followed by a close solar flyby to gain additional velocity. The specific window for a Lyra mission to Umwamua has a proposed launch between approximately 2030 and 2033 with the spacecraft potentially reaching Umamua in the 2050s. The European Space Ay's comet interceptor mission planned for launch around 2029 is designed specifically with this class of problem in mind. It will be stationed at the L2 Lrangee point approximately 930,000 mi from Earth where the gravity of the Earth and the Sun balance and it will wait there with its science instruments ready. When an interstellar object or a dynamically new comet making its first pass through the inner solar system is detected with enough lead time, comet interceptor will be deployed to intercept it, releasing multiple subspacecraft that will approach the target from different angles simultaneously for a multi-perspective flyby. If threeey atlas had been detected a year earlier than it was, comet interceptor would already have been in position to respond to it. The next interstellar visitor may arrive when the mission is already waiting. What did we learn from three eye atlas? more than from any previous interstellar object because we had more time, better instruments, and more of them. We learned that the chemistry of comet forming environments and other planetary systems can differ dramatically from the chemistry of our own outer solar system with dutarium to hydrogen ratios 30 times higher, suggesting formation in far older and colder environments than any known comet from our solar system. We learned that interstellar comets can be active, developing comas at distances as far from the sun as Saturn's orbit, which tells us something about the volatility of their surface compositions. We learned that an object formed in the early universe 10 to 12 billion years ago can survive intact for that entire span of time and arrive at our doorstep in a condition where we can analyze its composition and learn something about chemistry in the early galaxy. And we learned that the rate of interstellar object detection is increasing, which means the next encounter may be closer than anyone expects. When it comes, we'll be better prepared than we were for any of the first three. Omama came and left before we understood what it was. Borisoft came and told us that interstellar comets can look surprisingly like our own. Three eye atlas came and told us something older and stranger. That the building blocks of ancient planetary systems are drifting through the galaxy around us right now. that the chemistry of the early universe is encoded in icy bodies traveling between stars and that every so often one of them passes through our neighborhood close enough for us to read what it is carrying. The universe, it turns out, is constantly sending us messages from the deep past. We are only just learning how to read them.

[00:20:11]Subscribe now and turn on notifications so you are here when the next one arrives. Drop a comment below telling us what surprised you most about ThreeI Atlas. And share this with someone who has only heard the alien spacecraft theories and missed the real story. The real story is strange enough. Thanks for watching. Let us go deeper into the Umwam Mua story because it is the foundation on which everything about three Atlas is built and its unresolved questions add weight to everything we are learning now. When pan stars detected in October 2017, the initial designation was C 2017 U1, suggesting it might be a comet. That designation changed quickly to A 2017 U1 when no coma appeared, reclassifying it as an asteroid. Then the formal interstellar designation one I um mua followed after the trajectory analysis confirmed its origin outside our solar system. The name the Hawaiian Astronomical Society proposed Umuwa Mua meaning a messenger or scout from the distant past that has arrived first captured something that many astronomers felt intuitively about the object. The sense that something from very far away had briefly passed through and left more questions than it answered. The shape problem was not trivial. All the observations of Vumam Mua's brightness over time showed variations too large to be explained by a roughly spherical or even moderately irregular object. For a rotating body to show that degree of brightness variation, it would need to be either very elongated, roughly 10 to one in its longest to shortest dimension, or very flat. Both shapes are genuinely unusual among known solar system objects. Though elongated and flat shapes are not physically impossible, the cigar hypothesis and the pancake hypothesis produced different predictions about other observable properties of the object and the data available was limited enough that neither could be definitively confirmed before Umuam Mua disappeared from telescope range. The acceleration problem was harder to dismiss. When astronomers tracked Umamu Mua's trajectory precisely enough to calculate whether it was following a path determined purely by gravity, they found a small but significant deviation.

[00:22:07]something was pushing it slightly off the gravitational trajectory. For a comet, the most natural explanation would be outgassing. The rocket effect produced when ice sublimates and the resulting gas jets push the comet in the opposite direction. But there was no coma. No outging was detected by any instrument. Several teams proposed alternative natural explanations. A frozen hydrogen iceberg that would sublimate without producing visible dust. a chunk of frozen nitrogen similar to the material on Pluto's surface where the New Horizon's spacecraft observed vast plains of nitrogen ice, an unusually porous fractal dust structure comet whose surface would let radiation pressure act more effectively on its mass. Jav Lobo's light sail hypothesis proposed in a 2021 book and in papers co-authored with several colleagues argued that the acceleration was most consistent with radiation pressure acting on an object with an extremely large surface area relative to its mass like a sail only a fraction of a millimeter thick but hundreds of meters across. This is physically plausible.

[00:23:05]Light sails are real technology. The Japanese Icaros spacecraft demonstrated solar sail propulsion during its 2010 mission to Venus. Breakthrough Starshot, a privately funded initiative that Loe has been involved with, proposes using laser-powered light sails to accelerate small probes to a fraction of the speed of light for interstellar travel. Loe's argument was not that an alien civilization had definitely built Umu Awamua, but that the properties of the object were more consistent with a light sail than with any natural object we had ever observed, and that this possibility should be taken seriously and investigated scientifically rather than dismissed. The mainstream astronomical community's response focused on what the light sail hypothesis would require. An object produced by an advanced civilization, a propulsion mechanism different from anything we can confirm at interstellar distances, and the absence of any other evidence for the existence of such a civilization. Most researchers concluded that an unusual natural explanation, even one that had some ad hoc qualities, was more likely than a technological explanation that required multiple extraordinary assumptions. The discussion was scientifically valuable in one specific way. It sharpened the community's thinking about what kinds of observations could distinguish between a natural object with unusual properties and an artificial one. That sharpened thinking was directly applicable when three atlas arrived eight years later with properties that immediately distinguished it from umamua in the most important ways. The coma visible in three Atlas from May 2025 onward is the critical difference. A coma is not ambiguous. It is not a measurement artifact or a statistical interpretation. You can photograph it directly and watch it evolve over time as the comet heats up. The Gemini South telescope in Chile captured detailed images of the coma on August 27th, 2025, showing its structure clearly. ESA's Juice spacecraft traveling toward Jupiter for its primary mission studying that planet's moons happened to be positioned favorably to observe three Atlas during its inbound phase. And Juice's cameras and instruments captured detailed observations of the dust outflows in the inner coma morphology.

[00:25:04]The Mars Reconnaissance Orbiter captured images from Mars orbit. The James Webb Space Telescope contributed infrared observations that helped constrain the temperature and composition of the outgassing material. NASA's Hubble Space Telescope provided the best constraints on the nucleus size in August 2025. The speed of brightening was another distinguishing feature. As three Atlas fell inward toward the sun and the solar heating increased, its brightness increased much faster than two I Borisov had brightened during its equivalent approach. The brightening rate quantified by astronomers as a power law index of 3.8 compared to Borisov's roughly two indicated a much more rapid increase in activity as the distance from the sun decreased. This is consistent with a surface rich in highly volatile ices that sublimate energetically when heated, releasing large amounts of gas and dust. The comet reached its peak brightness of about 9th magnitude at perihelion on October 29th, 2025, requiring a small telescope to observe, but rewarding those who pointed one at it with an object clearly surrounded by a coma. The result that emerged from all of this observational work and that was formally published in Nature in June 2026 is the one that may be the most lasting scientific contribution of this encounter. A comet with a dutyium to hydrogen ratio more than 30 times higher than solar system comets. a speed that suggests it has been traveling through the interstellar medium for 10 to 12 billion years and a composition otherwise consistent with icy primitive material from a cold ancient environment. This object is a genuine sample from the early galaxy.

[00:26:33]Not a sample we can bring back to a laboratory, not a sample we can touch, but a sample we could analyze spectroscopically as it passed through.

[00:26:41]And the analysis told us something about chemistry in environments that formed billions of years before Earth existed.

[00:26:46]That is not a small thing. The next question that every astronomer who has studied the three known interstellar objects is now working on is what comes next? The answer depends heavily on how many of these objects exist in the galaxy and how often they pass close enough to the sun for current telescopes to detect them. Current models suggest that the detectable rate of interstellar objects should increase significantly over the next decade as the Vera Rubin Observatory in Chile, which began its legacy survey of space and time in 2025, scans the sky with sensitivity and speed that substantially exceeds any previous survey. The Vera Rubin Observatory's camera is the largest digital camera ever built for astronomy, capturing a patch of sky the size of 40 full moons in a single exposure to a depth that will detect objects far fainter and smaller than current surveys can reach.

[00:27:32]If the interstellar object flux is as high as current estimates suggest and if the diversity of interstellar objects reflects the diversity of planetary systems and formation environments across the galaxy, then the Vera Rubin Observatory may detect multiple new interstellar objects per year going forward. Each one a new data point in our growing understanding of chemistry and physics beyond our solar system.

[00:27:52]Three objects discovered over eight years, each one different from the others. Um, MMUA with its mysterious shape and acceleration and complete absence of commentary activity. Boris with its familiar commentary behavior and near solar system composition. And now 3II Atlas ancient beyond any comparison with anything in our own solar system formed when the universe was less than 4 billion years old.

[00:28:15]Carrying chemical evidence of environments we have never seen and cannot visit. The universe is delivering these to our doorstep at intervals that will almost certainly shorten as our ability to detect them improves. Every one of them carries information we cannot get any other way. And every one of them, after its brief passage through our solar system, continues its journey into the interstellar darkness, carrying whatever it carried when it arrived, unchanged by its brief encounter with our star, heading toward whatever comes next in a journey that started before our sun existed and will continue long after it is gone. If this kind of story is what you come here for, subscribe now and turn on notifications. Share this with someone who is still thinking about the alien spacecraft angle and has not yet heard the real science. The real science of 3i Atlas is, if anything, stranger and more remarkable than any fiction. Thanks for watching.