Comet 3I ATLAS: Unveiling the Secrets of an Ancient Interstellar Wanderer

[00:00:00] [SPEAKER_02] This is Space News Today Series 29 Episode 115, full broadcast on the 25th of September 2026. Coming up on Space Time, a comet older than the Sun, the nearby Super Earth planet that might be a candidate for life, and a new way to study the birth of the universe. All that and more coming up on Space

[00:00:22] [SPEAKER_00] Time. Welcome to Space Time with Stuart Gary. Astronomers have found new clues about the

[00:00:45] [SPEAKER_02] origin of interstellar comet 3I ATLAS, suggesting it may be more than twice as old as our Sun and Solar System. The findings are reported in the journal Nature Astronomy, based on observations by the European Southern Observatory's Very Large Telescope in Chile, which studied the composition of the alien visitor, which is now considered to be the brightest interstellar object ever seen in detail. By measuring specific chemical fingerprints, the first observations of this kind for a comet formed

[00:01:13] [SPEAKER_02] outside our solar system, the authors found that 3I ATLAS likely originated in the outskirts of an older star system. One of the study's authors, Cyril Opetem from the University of Edinburgh, says the findings are shining new light on the formation history of this comet. Interstellar comets are icy objects formed around stars other than the Sun that have occasionally wandered into our solar system. Opetem says they're sort of fossils from a planetary formation process that happen far away,

[00:01:42] [SPEAKER_02] but which gives scientists a chance to study them up close. 3I ATLAS is the third interstellar object ever discovered. It follows 1I Amalmauer back in 2017 and 2I Burishev in 2019. It was found as it was approaching the Sun spending enough time in our solar system for astronomers to study it in some detail. While it was difficult to measure the composition of the first two interstellar objects, with no gas detected from Amalmauer and Burishev being too faint, this was not the case for 3I ATLAS.

[00:02:12] [SPEAKER_02] Thanks to the object's unprecedented brightness, the authors were able to measure the comet's isotopic ratios, the relative amounts of different forms of the same element. They measured the ratios of carbon and nitrogen isotopes in cyanide molecules present in the gas around the comet. These ratios are a good indicator of a comet's origin as they're sensitive to the physical conditions in the formation environment and not expected to change much as the comet travels through space. Unlike comets from our solar system,

[00:02:40] [SPEAKER_02] 3I ATLAS was found to carry unusually high carbon and nitrogen isotopic ratios. A similar study led by Martin Kordina from NASA's Goddard Space Flight Center in Greenbelt, Maryland's which was published in last month's Nature found a similar isotopic ratio for carbon as well as elevated levels of deuterium, a heavy form of hydrogen. That study used data from NASA's Webb Space Telescope. Overall, the findings by Opitum's team indicate that the comet likely formed in the

[00:03:07] [SPEAKER_02] outer regions of an old low-metallicity star. Now, low-metallicity stars are ones with compositions containing few elements heavier than hydrogen and helium. These types of stars are thought to have formed when the universe was much younger and less chemically rich than what it is now. Therefore, the authors suspect 3I ATLAS originated around a star much older than our Sun, and maybe more than twice as old as the solar system. This interstellar traveller was first detected by NASA's Asteroid Terrestrial

[00:03:37] [SPEAKER_02] Impact Last Alert System, or ATLAS, back on July 1st in 2025. David Farnosier, from NASA's Jet Propulsion Laboratory in Pasadena, California, says it was about 670 million kilometres from the Sun within the orbit

[00:03:50] [SPEAKER_00] of Jupiter when it was first discovered. 3I ATLAS was discovered on July 1st by the NASA-funded ATLAS survey. It was discovered using their telescope at Rio Urtado in Chile, and it was first detected as a speck of light moving relative to background stars. We collected a good amount of data, more than 100 observations. We know its trajectory fairly well. We know it came from outside the solar solar system. From images, we also saw that this object is active, which means that around the

[00:04:18] [SPEAKER_00] nucleus there is some coma, which is an indication that this object is in fact a comet. Right now it's hard to say how big this object is because being active, the brightness that we see is partially due to the size of the object, but also it's partially due to the activity, and so we cannot really pinpoint the nucleus size directly. We have to better understand how active this object is, and then we can refine the size estimate and get a good idea. It's moving at a velocity of about 135,000 miles per hour,

[00:04:47] [SPEAKER_00] so it's going really fast. For that distance from the Sun, this is really exceptional. You have to be an interstellar object to be going that fast at that distance from the Sun. The more data we get, the better we can measure the position of this object as it travels through the solar system and it moves out of it. But we also want to collect physical characterization data. For instance, we would like to understand better what the size of this object could, the levels of activity. We're just bracing ourselves to get as much information as possible. We're really excited about these objects. So far we've discovered

[00:05:16] [SPEAKER_00] three interstellar objects. The first one was Oumuamu in 2017, the second one Borisov in 2019, and now we have the third one, 3I Atlas. So it's a rare opportunity and as a scientific community we want to collect as many data as possible to characterize this object and learn as much as we can. That's David Fanasia from NASA's

[00:05:36] [SPEAKER_02] Jet Propulsion Laboratory in Pasadena, California. And this is Space Time. Still to come, the nearby super-Earth planet that may be a candidate for life and a new way to study the birth of the universe.

[00:05:50] [SPEAKER_02] All that and more still to come on Space Time. Astronomers have taken a closer look at a nearby exoplanet, finding it may be more Earth-like than previously thought. The planet catalogued as GJ3378b

[00:06:18] [SPEAKER_02] orbits a small spectrotype M red dwarf star 25 light-years away in the direction of the northern constellation Camilla Pedales. A report in the Astrophysical Journal claims the planet orbits within the star's habitable zone. That's the region where temperatures could allow liquid water to exist on a planet's surface, thereby making this planet a candidate to host life. The study's lead author Paul Robertson from the University of California, Irvine says the

[00:06:45] [SPEAKER_02] mantra is follow the water. It's the one thing every known living thing on Earth needs. So that's the first thing astronomers look for when trying to find environments that could sustain life, at least life as we know it. So Robertson and colleagues took a closer look and found that it may be more Earth-like than they previously thought. Red dwarfs are the smallest coolest group of stars. They have surface

[00:07:07] [SPEAKER_02] temperatures of around 2400 to 3900 degrees, that compares to the Sun's 6000 degrees. They're also much smaller and dimmer than our Sun, and often appear reddish, hence their name. But red dwarfs are the most common type of star in the galaxy, making up some 70% of the entire galactic stellar population. However, the problem with red dwarfs is they tend to launch stellar flares far more often than sun-like

[00:07:33] [SPEAKER_02] stars. And this intense stellar flare activity can erode a planet's atmosphere, irradiating its surface and any life that may be on that surface. Also because these stars are so dim, and Earth-like planets are so small, they can be very difficult to detect and require specialised instrumentation. So to learn more about JG 3378b, the authors used the Habitable Zone Planet Finder instrument on the Hobbie Eberle telescope at the MacDonald Observatory in order to study its host star. As a planet

[00:08:03] [SPEAKER_02] orbits star, its gravitational force tugs on the star. This creates a slight wobble, a Doppler shift, which is visible on the host star. And that Doppler shift can be used to calculate a planet's mass and orbit. The Habitable Zone Planet Finder is optimised to use infrared light. As a star gets smaller and they get cooler, most of their energy comes out in infrared wavelengths. So astronomers put an infrared spectrometer on the 10-metre telescope, giving them more raw-like collecting power to observe these

[00:08:33] [SPEAKER_02] faint stars. GJ 3378b is described as a super-Earth, that is, a terrestrial rocky planet larger than the Earth but not so big as to hold onto a thick atmosphere that would crush any life on its surface. When the planet was first discovered in 2024, it was thought to be about 5 times the mass of the Earth, but this new analysis shows it's closer to around 2.3 times Earth's mass. And that change increases the

[00:08:58] [SPEAKER_02] likelihood that the planet doesn't hold a smothering atmosphere. The authors also refined the planet's orbit down from 25 Earth days to 21. Now even though both of these are tiny orbits, in comparison the Earth has a 365 day orbit, with a host star roughly a third the size of our Sun, that proximity is necessary to place the planet within that star's Habitable Zone. Now that said, its smaller orbit also subjects the planet to intense radiation which could evaporate any atmosphere present.

[00:09:26] [SPEAKER_02] So, more observations will be needed for astronomers to be sure. This is Space Time. Still to come. A new way to study the birth of the universe, and later in the science report, the discovery of a half-billion year old fossil which has rewritten the origin story of starfish. All that and more still to come, on Space Time. Scientists have discovered

[00:09:55] [SPEAKER_02] a new way to create a glycogluon plasma, the first matter to form in our universe. The findings, reported in the journal Physical Review Letters, opens a new window on the first microseconds after the Big Bang, 13.8 billion years ago. What happened in those first moments of the universe, before the building blocks of life in the world as we know it came into existence? Physicists at CERN, the European Organization for Nuclear Research, are trying to answer this question by recreating some of the extreme conditions that

[00:10:25] [SPEAKER_02] prevailed in the universe at the very beginning of time. Now, researchers from the Niels Bohr Institute, together with colleagues from the Alice Collaboration at CERN's Large Hadron Collider, the world's biggest atom smasher, have come one step closer to understanding those conditions. At CERN, physicists collide atomic nuclei at some 99.9999% the speed of light, in the process creating the tiny droplets of primordial matter that filled the universe during its first millionth of a second

[00:10:52] [SPEAKER_02] of creation. This substance is known as quark-gluon plasma and is thought to be the earliest form of matter in our universe. For many years, scientists have assumed that creating this plasma required collisions between very heavy atomic nuclei, such as lead. But physicists from the Niels Bohr Institute have now succeeded in creating this primordial matter by smashing much smaller nuclei of oxygen-16

[00:11:17] [SPEAKER_02] and neon-20 together. The study's lead author, Zhao Zhu from the Niels Bohr Institute and the University of Copenhagen, says they've pushed the boundaries for how small the atomic nuclei can be while still recreating this quark-gluon plasma. The discovery means scientists now know more about the fundamental conditions required for matter to transition into this extreme state. This, in turn, will help researchers better understand how plasma behaved during the first moments of

[00:11:45] [SPEAKER_02] the universe and how it later evolved into the forms of matter that everything we see around us today is made of. When the atomic nuclei collide, their constituents are transformed into tiny droplets of quark-gluon plasma that exist for just a fraction of a second. This droplet of extremely hot matter then expands. Researchers can't observe the plasma directly, but they can measure the particles that this matter

[00:12:11] [SPEAKER_02] turns into shortly afterwards. And the movement pattern of these particles reveals the shape of the atomic nucleus. Collisions between two oxygen nuclei produce a more rounded pattern, while collisions involving neon produce a more bowling pin-shaped pattern. The particles from the primordial matter are directly governed by the geometric shape of their atomic nucleus. So if two atomic nuclei being smashed together as spherical, they'll produce one pattern, and if they're shaped like bowling pins, they'll produce

[00:12:39] [SPEAKER_02] another. By studying how the particles move after the collision, scientists can gain fresh insights into atomic nuclei that would otherwise be difficult to obtain. The authors describe it as being like shining a light on an object and seeing its shadow. You can't see the object directly, but its shadow reveals its shape. In the same way, the movement of these particles reveals the geometric shape of the atomic nuclei present at the beginning of the collision. The shape of an atomic nucleus is not merely a matter of geometry.

[00:13:08] [SPEAKER_02] It reveals how protons and neutrons are organized, and provides important information about the strong nuclear force, one of nature's four fundamental forces which scientists are still trying to fully understand, the others being the weak nuclear force, the electromagnetic force and gravity. That assumes, of course, that gravity really is a force, which it's probably not. Until now, physicists have primarily investigated nuclear structure at low energies by studying

[00:13:34] [SPEAKER_02] things like the rotation and vibration of atomic nuclei. Zhao says the precise understanding of nuclear structure helps scientists understand the strong nuclear force. But instead of carefully investigating nuclei at low energies, they've smashed together at the highest energies, allowing scientists to read their shape from the imprint they leave behind. Researchers still don't know the exact boundary when a quark glue on plasma can be created. So the next step will be to try experiments with even lighter nuclei, such as

[00:14:03] [SPEAKER_02] helium-4. The experiment will allow scientists to both learn about the structure of atomic nuclei, and to gain a better understanding of what happened during the birth of the universe. And it turns out these two things may be much more closely connected than previously thought.

[00:14:20] [SPEAKER_02] This is Space Time. And time out to take another brief look at some of the other stories making news in science this week with the Science Report.

[00:14:44] [SPEAKER_02] A major sexual health clinic in Melbourne has seen an almost doubling over the past decade of women testing positive for gonorrhea. The authors analysed data from the clinic between 2015 and 2024, looking for the characteristics of women contracting gonorrhea, amid a rise in sexually transmitted diseases among women in Melbourne in recent years. The findings reported in the journal Sexual Health show gonorrhea cases increased from 1.3% in 2015 to 2.3% in 2024.

[00:15:13] [SPEAKER_02] The authors say the women diagnosed were predominantly young, had multiple casual male partners and used condoms inconsistently. Oral gonorrhea saw the largest increase in cases during the study. The New South Wales state government has just passed new legislation allowing people to drive when under the influence of medicinal cannabis.

[00:15:38] [SPEAKER_02] The passing of this bill comes as Canadian researchers have analysed 40 regular edible cannabis users, testing their driving skills in a simulator before and after eating THC gummies. The findings reported in the Journal of the American Medical Association show that higher doses of THC led to poorer lane control, slower reaction times and less consistent speeds. And that's despite the participants' blood tests showed they remained below the legal thresholds for driving with cannabis.

[00:16:06] [SPEAKER_02] In Canada, New Zealand and now New South Wales, that legal limit is 5 nanograms per milliliter. Human pollution affects our entire planet, destroying environments wherever people go. Now a report in the journal PLOS One describes how researchers have found plastic litter, more than half of their remotely operated dives to the bottom of the Mardel Plata Canyon near Argentina, 3 km below the sea surface.

[00:16:32] [SPEAKER_02] After 17 dives in 2025, scientists analysed approximately 240 hours of video footage, finding some stationary creatures like starfish and corals had attached to the trash dumped by humans, including packets of fried noodles, plastic cups and even old boots. A few months earlier expeditions found cans and plastic bags on the bottom of the Mariana Trench, the planet's deepest fissure in the western Pacific Ocean.

[00:16:58] [SPEAKER_02] The discovery of a half-billion-year-old fossil has rewritten the origin history of starfish. Palaeontologists uncovered the 518-million-year-old remains in southwestern China. It comes from a period of rapid evolutionary development known as the Cambrian Explosion, when most major animal groups first appeared in the fossil record. The new find, named Eugenio glunitotonica, are thought to be closely related to the last common ancestor of Ambuloclarians,

[00:17:25] [SPEAKER_02] the modern group that includes starfish, sea stars, sea urchins and acorn worms. A report in the journal Current Biology shows the new discovery ate their food using tentacles, and not passively using their gills as previously thought. A pseudoscience and UFO researcher says he's uncovered evidence that four different types of extraterrestrial alien species have visited our planet.

[00:17:48] [SPEAKER_02] Hal Puthoff, a former Advanced Aerospace Weapon System Applications Program advisor and CIA-funded researcher, claims bodies of four different species have been recovered from various UFO crashes by the US government. But as the sceptic's Tim Mendham points out, he's provided no evidence to support his claims.

[00:18:06] [SPEAKER_01] They all look a bit humanoid, which is, I don't know, to me surprising. I don't know why aliens always have to look like humans. No octopus people. No, no, no, no sentient bacteria or anything like that. There's the lizard people who look like lizards, have tails. So there's the Nordic who look very sort of glamorous Norwegian-looking people. There's the insect people who are a bit scary, look like praying mantises. And of course, there's the greys, the cliched modern-looking little people, big heads, big eyes, that sort of thing.

[00:18:31] [SPEAKER_01] They all have sort of hands, fingers, eyes. Obviously scary in some cases, some cases benign. You've got to look at the people who are promoting this stuff. I mean, obviously there's no evidence for it at all. There's just conjecture made up, cliches, memes, whatever. Some of the people promoting it. One in particular recently is Dr. Hal Puthoff, who was a former Advanced Aerospace Weapon Systems Application Program advisor for it. He was also involved in a place called the Stanford Research Institute back in the 70s with a Harold Targ partner,

[00:19:00] [SPEAKER_01] who were investigating Yuri Geller. And they came out very much in favor of Yuri Geller, saying he had definite spoon bending talents and all sorts of psychic powers and things. The protocols that they used in their laboratory testing were very dodgy, or at least questionable. Let's put it that way. And certainly someone as sceptic as noted as James Randi, the late James Randi described them as the Laurel and Hardy of parapsychology research. But he has come out recently and said that there is definitely these four types of UFO occupants.

[00:19:26] [SPEAKER_01] He hasn't seen them, of course, but he's heard of them. He's said testimony from members of supposed crash retrieval programs who tend not to come forward to actually talk about their work, because they're feared for their lives. It's annoying that all these people with evidence don't come forward with it, but therefore you have to say, well, what evidence do they have? I could say the moon is made of cheese and people say, where's the evidence? Well, I can't give it to you because it's secret. And you say, right, okay, I'm supposed to believe that. So all these people who are claiming UFOs,

[00:19:51] [SPEAKER_01] and they know of someone who knows of someone who has seen these occupants of interplanetary craft. There's no evidence for it. And you get people like Hal Putoff, who might be going through attention deficit disorder. He wants to sort of put his hand up again, even in his age and years or something, because he has been around a long time since the early seventies. His record is not crash shot. So as a source of information despite the fact he supposedly has this sort of research background, it's not necessarily as exciting as it might sound to be, not necessarily as

[00:20:20] [SPEAKER_01] respectable or reliable as it might sound to be. Saying I worked with the CIA on projects in the seventies, there's nothing particularly exciting. So you see how he was funding anything going and came out with nothing at the end. But anyway, Hal Putoff is saying there's four different types of aliens, all of whom look humanish and none of them, any evidence for them at all. There's a documentary made about disclosure things. Let's call it a mockumentary. It's a mockumentary with

[00:20:47] [SPEAKER_01] a lot of puffery before a claim out. And people have seen it, so there's nothing new there. It's all the same old, same old, same characters who keep appearing and being interviewed. Of course, it's going to hit the preamble to the film, Spielberg film called Disclosure. It talks about alien interaction with people, et cetera, all sorts of, you know, they walk among us type things. No real evidence. And a lot of claims, but no evidence. And that goes on, that has been going on since the 1940s. And every researcher of UFOs has always said, any day now, it's going to be the great reveal. And

[00:21:14] [SPEAKER_01] that day has never arisen. So we're waiting. They've never presented, never presented any irrefutable, anything close to irrefutable evidence, just claims.

[00:21:22] [SPEAKER_02] That's the skeptics Tim Mendham. And this is Space Time. And that's the show for now. Space Time is available every Monday, Wednesday and Friday through Bytes.com, SoundCloud, YouTube,

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[00:22:30] [SPEAKER_01] This has been another quality podcast production from Bytes.com.