3I/ATLAS Live Updates: Comet’s Location from Earth, Scientists’ Alien Theories 

Comet 3I/ATLAS was discovered on July 1, 2025, by the NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) survey telescope in Rio Hurtado, Chile, and given its official name, 3I/ATLAS.

The discovery sparked a scientific frenzy as it is only the third interstellar comet, meaning it originates from another solar system, to be discovered.

NASA has determined it "poses no threat to Earth," and that it will remain at a distance of at least 240 million kilometers from the planet.

NASA has assured that the interstellar comet 3I/ATLAS will maintain a safe distance from Earth during its passage through the solar system.

The comet’s closest approach will be approximately 1.8 astronomical units away—roughly 170 million miles or 270 million kilometers—eliminating any risk of impact.

3I/ATLAS is thought to be at least 7 billion years old.

That would make the interstellar object twice as old as Earth, and the oldest comet every recorded.

3I/ATLAS is not expected hit Earth, with NASA determining it "poses no threat," and that it will remain at a distance of at least 240 million kilometers from the planet - around twice the distance between Earth and the Sun.

3I/ATLAS is on a hyperbolic trajectory, meaning it’s not bound to the Sun by gravity like ordinary comets are. Instead, it’s an interstellar object, passing through our solar system just once before continuing back into deep space. This trajectory ensures that it will not loop around again or come near Earth in the future. The comet reached its closest point to the Sun (perihelion) around October 29–30, 2025, and it will now move steadily away from both the Sun and Earth.

Because of this vast distance and its outbound path, 3I/ATLAS poses no impact threat now or in the foreseeable future. NASA and the Minor Planet Center continue to track its motion, and all available orbital solutions confirm it will remain safely far from Earth.

The interstellar comet 3I/ATLAS reached its closest point to the Sun around October 29–30, 2025, coming within about 1.4 AU of it — just inside Mars’s orbit. During this time, it was positioned behind the Sun from Earth’s view, making it difficult to observe. Like the earlier visitors 1I/‘Oumuamua and 2I/Borisov, 3I/ATLAS follows a hyperbolic, unbound path, meaning it entered our Solar System from interstellar space and will eventually leave again.

Before perihelion, the comet passed close to Mars on October 3, 2025, at a distance of about 28 million kilometers. It will make its closest approach to Earth on December 19, 2025, although it will still be a distant 1.8 AU away. After that, it’s expected to pass near Jupiter on March 16, 2026, within roughly 50 million kilometers, before heading back out of the Solar System for good.

Scientists are closely tracking 3I/ATLAS to study how it behaves as it recedes from the Sun. Its outgassing and tail formation could reveal clues about its composition and the environment where it originated beyond our Solar System. As it moves away, it will gradually become more visible from Earth again — offering a rare final opportunity to observe an object from another star system.

A Harvard University professor has said 3I/ATLAS, a comet shrouded in controversy, experienced a sudden "nongravitational" acceleration while passing around the sun, which he believes adds to other potential evidence that 3I/ATLAS is "alien technology."

Abraham "Avi" Loeb, a professor of science and the director of the Institute for Theory and Computation at Harvard, has become well-known for his controversial views on the comet. Recently, he wrote in an article on Medium that the Manhattan-size 3I/ATLAS accelerated when it reached its closest point to the sun.

Loeb told Newsweek that on Thursday night, he calculated that 3I/ATLAS "should have lost at least 10 percent of its mass in order to get this nongravitational acceleration out of outgassing."

This means that "we should see a dense cloud of gas around it in November and December," he added.

Read in full from Jasmine Laws on Newsweek.

Harvard astrophysicist Avi Loeb is urging NASA to release high-resolution imagery of 3I/ATLAS, taken by its HiRise camera on the Mars Reconnaissance Orbiter earlier this month.

Loeb, who has proposed the controversial idea that 3I/ATLAS may not be a natural comet but have alien origins, said that images taken on October 2 from the orbiter could provide crucial answers about the comet.

“The politics of the day should not sabotage science. They have the data. They should share it with scientists,” Loeb, referring to NASA, told “Elizabeth Vargas Reports” on Thursday. “They can wait with any press release."

3I/ATLAS is most likely a comet of natural origin, but it has several anomalies that have sparked huge interest in the science world.

It is one of only three comets discovered that originates from outside our solar system.

Its nucleus is about a million times bigger than 1I/`Oumuamua and a thousand times more massive than 2I/Borisov. It is also moving faster than both.

The gas plume around 3I/ATLAS contains much more nickel than iron, and a nickel to cyanide ratio much higher than other comets.

3I/ATLAS' gas plume also contains only 4 percent water by mass. Typically ice makes up around half of a comet's mass.

3I/ATLAS showed extreme negative polarization, which is incredibly rare for comets.

On Wednesday and Thursday, comet 3I/ATLAS made its closest pass to the Sun, known as its perihelion.

Newly released images appear to show the alien object releasing a jet of gas and dust toward the sun as much of its ice was melted by the Sun.

It has now completed its perihelion, and is continuing on its path through our solar system.

Comet 3I/ATLAS carries a name that reflects both its origin and its discoverers. The “ATLAS” designation honors the Asteroid Terrestrial-impact Last Alert System survey team, which first identified the object. The prefix “I” stands for “interstellar,” marking it as a visitor from beyond our solar system.

This comet is the third confirmed interstellar object to pass through our solar neighborhood, following 1I/ʻOumuamua in 2017 and 2I/Borisov in 2019. The number “3” in its name denotes its sequence in this rare category of cosmic travelers.

Harvard University professor Avi Loeb said the interstellar object 3I/ATLAS had shown unusual heat and colour characteristics as it reached its closest point to the Sun over the past day or so, compounding the mystery surrounding the comet.

“We have a report that the object got much brighter than expected, much brighter than any previous comet from the solar system did, as it approached the sun,” Loeb said in an interview with Newsmax, citing instruments that he said were able to observe the object when it came closest to the sun, or perihelion.

“And moreover the color of the object is blue, bluer than the sun and that’s very surprising because usually when there is dust around an object, it should make it red and we expect the surface temperature of the object to be an order of magnitude lower than the surface temperature of the sun,” said the theoretical physicist.

“The object should be much cooler than the sun, so redder than the sun, nevertheless the data shows that it’s bluer than the sun meaning a very high temperature…Why would it be bluer than the sun?”

“It seems like it’s even more weird than I thought. The blue color is something we need to understand, (we) haven’t had time to figure out the physics behind it,” he said.

Loeb said earlier the comet's behavior at perihelion would constitute the “acid test” to help determine if the interstellar object first detected in July is as it appears - a comet - or something more extraterrestrial.

Comets are often referred to as "dirty snowballs" because of their composition.

They are made up of a combination of ice, mixed with dust and rocks - like a snowball made of a day-old snow that has had dirt trodden in.

When comets travel near stars, such as our Sun, heat causes them to release gas and dust, which creates their signature tails.

In the case of 3I/ATLAS, scientists we keen to observe it passing the Sun to learn clues about its composition, and the solar system it came from.

The interstellar comet 3I/ATLAS reached its closest point to the Sun around October 29–30, 2025, coming within about 1.4 AU of it — just inside Mars’s orbit. During this time, it was positioned behind the Sun from Earth’s view, making it difficult to observe. Like the earlier visitors 1I/‘Oumuamua and 2I/Borisov, 3I/ATLAS follows a hyperbolic, unbound path, meaning it entered our Solar System from interstellar space and will eventually leave again.

Before perihelion, the comet passed close to Mars on October 3, 2025, at a distance of about 28 million kilometers. It will make its closest approach to Earth on December 19, 2025, although it will still be a distant 1.8 AU away. After that, it’s expected to pass near Jupiter on March 16, 2026, within roughly 50 million kilometers, before heading back out of the Solar System for good.

Scientists are closely tracking 3I/ATLAS to study how it behaves as it recedes from the Sun. Its outgassing and tail formation could reveal clues about its composition and the environment where it originated beyond our Solar System. As it moves away, it will gradually become more visible from Earth again — offering a rare final opportunity to observe an object from another star system.

3I/ATLAS is not expected hit Earth, with NASA determining it "poses no threat," and that it will remain at a distance of at least 240 million kilometers from the planet - around twice the distance between Earth and the Sun.

3I/ATLAS is on a hyperbolic trajectory, meaning it’s not bound to the Sun by gravity like ordinary comets are. Instead, it’s an interstellar object, passing through our solar system just once before continuing back into deep space. This trajectory ensures that it will not loop around again or come near Earth in the future. The comet reached its closest point to the Sun (perihelion) around October 29–30, 2025, and it will now move steadily away from both the Sun and Earth.

Because of this vast distance and its outbound path, 3I/ATLAS poses no impact threat now or in the foreseeable future. NASA and the Minor Planet Center continue to track its motion, and all available orbital solutions confirm it will remain safely far from Earth.

According to a live tracker at TheSkyLive, the comet is currently about 342,767,457 kilometers from Earth, passing through the constellation of Virgo.

The comet is on a hyperbolic trajectory and so will not remain in the Solar System indefinitely.

The comet was first discovered on July 1 by the NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) survey telescope in Rio Hurtado, Chile, and given its official name, 3I/ATLAS.

At the time, it was located about 670 million kilometers from Earth. NASA determined it "poses no threat to Earth," and that it will remain at a distance of at least 240 million kilometers from the planet.

Before 3I/ATLAS, there were two other interstellar objects discovered. These were 1I/`Oumuamua and 2I/Borisov, discovered in 2017 and 2019, respectively.

In the scientific community, 3I/ATLAS is widely accepted as a comet. Darryl Seligman, a professor in the physics and astronomy department at Michigan State University, told Newsweek there is "clear-cut evidence of cometary activity–it was and still is behaving entirely in line with solar system comets at large distances."

Seligman said that for some comets that get close to the sun, it is possible to see "nickel vapor because there is nickel in the dust grains coming off of it, and that vaporizes."

This usually happens at "much higher temperatures than 3I/ATLAS was at," he said, but added that this was something "we have seen in solar system comets and also in the last interstellar comet 2I/Borisov."

"This behavior of nickel being seen at far distances where it is too cold for direct nickel sublimation has been seen in solar system comets," he said. "It probably means that the ice structure is complex in 3I/ATLAS, and that nickel was in the ice along with a lot of other species."

NASA has triggered its planetary defense protocol in response to unusual behavior observed in Comet 3I/ATLAS, an interstellar object discovered in July 2025, per CPG. The comet, which recently reached perihelion, has displayed erratic changes in speed, brightness, and trajectory, prompting global scientific concern.

The agency mobilized the International Asteroid Alert Network to coordinate data sharing and simulations, aiming to assess potential risks. A newly formed international task force is investigating whether the comet’s anomalies stem from natural causes or suggest something more extraordinary.

3I/ATLAS is notable for its massive size—over 33 billion tons—and its metallic composition, including nearly pure nickel and traces of nickel tetracarbonyl, a compound rarely found in nature. These features, along with its fluctuating tail and light emissions, have fueled speculation about its origin.

While NASA maintains the object poses no threat and likely has natural explanations, the comet’s behavior continues to challenge conventional models, offering scientists a rare opportunity to study material from beyond the solar system.

Physicist Brian Cox described the 3i/Atlas as “a message from a dead world.” The comet, which originated outside our solar system, is only the third known interstellar visitor after ‘Oumuamua and 2I/Borisov.

In a recent social media post, Cox dismissed online speculation about extraterrestrial origins, affirming that ATLAS is a natural formation composed of carbon dioxide, water ice, and cosmic dust. He emphasized its predictable orbit, noting it will pass the Sun and continue drifting through the galaxy.

Cox also reflected on the comet’s more profound significance, imagining future civilizations encountering it as a relic from a long-lost planetary system. Scientists estimate ATLAS may be 7.5 billion years old, predating the Sun and offering a rare glimpse into ancient cosmic material.

As researchers prepare to study its composition, Cox’s remarks serve as a reminder that the universe’s natural wonders often outshine fiction. For him, the silent journey of ATLAS is “wonderful enough.”

The interstellar comet 3I/ATLAS, roughly the size of Manhattan, reached its closest approach to the Sun on October 30, passing just inside Mars’ orbit at a distance of 130 million miles. Despite its proximity, the comet remains hidden from Earth due to solar glare and won’t be visible to ground-based or orbital telescopes until later in November.

As the third known interstellar object to enter our solar system, ATLAS has sparked scientific interest and speculation. Harvard astrophysicist Avi Loeb has questioned its trajectory and behavior, suggesting it could be an artificial probe due to its unusual acceleration and particle jet pointing toward the Sun—known as an anti-tail.

Loeb also accused NASA of withholding a key image taken by the Mars Reconnaissance Orbiter, though the agency has not confirmed such a photo or any threat posed by the comet. While ATLAS will pass within 170 million miles of Earth, experts maintain it poses no danger. Several spacecraft, including missions near Mars and Jupiter, are expected to monitor its passage.

Stargazers won’t be able to get approach to the Sun this week, even with terrestrial telescopes, as it gets hidden by the solar glare.

But spacecraft currently in our solar system, including NASA’s mission to the Psyche asteroid, and the Lucy mission to Jupiter’s Trojan asteroids, and European Space Agency’s Jupiter Icy moons Explorer (JUICE), should be able to get a much view.

JUICE will likely have the best view of 3I/ATLAS but it won't be able to send the images to Earth until next February.

3I/ATLAS is thought to be at least 7 billion years old.

That would make the interstellar object twice as old as Earth, and the oldest comet every recorded.

An interstellar comet currently at perihelion—its closest approach to the Sun—is generating intense heat, estimated at 770 watts per square meter. The object, temporarily obscured from Earth by solar glare, is being closely tracked by spacecraft, including those operated by NASA.

Though invisible to ground-based observers for now, astronomers anticipate the comet will reemerge in early November, becoming visible through telescopes as it moves away from the Sun’s overpowering light. Scientists are monitoring its behavior to gather insights into its composition and origin.

Harvard astrophysicist Avi Loeb has raised concerns about transparency in space research, claiming that authorities withheld key information about the interstellar comet 3I/ATLAS. Speaking on the Joe Rogan Experience, Loeb highlighted a missed opportunity for scientific insight, noting that the most transparent image of the object was captured on October 2, 2025, when it passed within 30 million kilometers of Mars.

Loeb dismissed speculation about alien origins, quipping that the situation reflects “terrestrial stupidity” rather than extraterrestrial intelligence. His remarks add to ongoing debates about how space agencies handle public access to astronomical data, especially regarding rare interstellar visitors.

Comet 3I/ATLAS carries a name that reflects both its origin and its discoverers. The “ATLAS” designation honors the Asteroid Terrestrial-impact Last Alert System survey team, which first identified the object. The prefix “I” stands for “interstellar,” marking it as a visitor from beyond our solar system.

This comet is the third confirmed interstellar object to pass through our solar neighborhood, following 1I/ʻOumuamua in 2017 and 2I/Borisov in 2019. The number “3” in its name denotes its sequence in this rare category of cosmic travelers.

NASA has assured that the interstellar comet 3I/ATLAS will maintain a safe distance from Earth during its passage through the solar system. The comet’s closest approach will be approximately 1.8 astronomical units away—roughly 170 million miles or 270 million kilometers—eliminating any risk of impact.

3I/ATLAS is expected to reach its perihelion, the point nearest to the Sun, around October 30, 2025.

The interstellar comet 3I/ATLAS is estimated to be around 7 billion years old—making it significantly older than Earth, which formed roughly 4.5 billion years ago. This ancient traveler from beyond our solar system is offering scientists a rare glimpse into primordial cosmic material.

Recent analyses suggest that 3I/ATLAS contains unusually high concentrations of carbon dioxide and nickel, setting it apart from native solar system comets. These chemical anomalies could provide valuable clues about the conditions in distant star systems and the diversity of cometary formation across the galaxy.

The interstellar comet 3I/ATLAS is currently traversing our solar system at extraordinary speed, drawing intense interest from astronomers worldwide. Unlike typical comets, 3I/ATLAS originated beyond our solar neighborhood, offering scientists a rare chance to study alien material up close.

NASA, in collaboration with international space agencies, has launched a comprehensive observation effort to analyze the comet’s composition, luminosity, and trajectory. This initiative aims to refine methods for identifying and tracking fast-moving interstellar objects, which could be vital for future planetary defense.

As 3I/ATLAS interacts with the Sun’s gravitational field, researchers hope to gain insights that will enhance early-warning systems for potential near-Earth threats. Though the comet poses no danger to Earth, its brief visit presents a valuable opportunity to advance space science and security.

The interstellar comet 3I/ATLAS is racing through our solar system at a staggering 210,000 kilometers per hour, having already passed Mars. Its unusual characteristics—including its brightness, composition, and prolonged lack of a visible tail—have intrigued astronomers, though much about the object remains unknown. Scientists expect the comet to quietly exit the solar system in the coming months.

Currently, 3I/ATLAS is hidden from view, positioned behind the Sun in what astronomers call solar conjunction. This alignment, which occurred around October 22, renders the comet invisible from Earth. It is also approaching perihelion—the point in its orbit closest to the Sun—expected between October 29 and 30. After this, the comet will begin its outward journey.

Due to its extreme distance—270 million kilometers at its closest approach—3I/ATLAS will not be visible to the naked eye. Only telescopes with apertures of at least eight inches may be able to detect it when it reemerges from the Sun’s glare, likely not before December 2025.

Despite speculative chatter about its trajectory, 3I/ATLAS poses no threat to Earth. Its hyperbolic path confirms it is not gravitationally bound to the Sun and will eventually continue its journey into interstellar space.

Comets are usually named for the astronomers or teams that first spot them—in this case, the ATLAS survey team. Short for Asteroid Terrestrial-impact Last Alert System, ATLAS is a NASA-funded sky survey based in Hawaii, designed to detect asteroids and comets that could pose a threat to Earth. Its wide-field telescopes scan the entire visible sky several times a night, flagging fast-moving or unusual objects.

The “I” in the comet’s name stands for “interstellar,” signifying that this celestial visitor originated beyond our solar system. The “3” marks its place as only the third known interstellar object ever discovered, following ‘Oumuamua in 2017 and Borisov in 2019.

...

As interstellar comet 3I/ATLAS moves closer to the Sun, astronomers have observed it releasing a jet of material.

The action is not uncommon for comets, which are made primarily of ice, and can melt from the solar heat as they pass by the Sun. The melting ice is then released as a jet of vapor.

Scientists have been observing the comet and its glowing trail or coma using powerful telescopes such as Hubble and the James Webb Space Telescope.

The European Space Agency (ESA) quickly ruled out sending a spacecraft to study the comet due to its high speed and the limited time in our solar system.

Comet 3I/ATLAS was discovered on July 1, 2025, by the NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) survey telescope in Rio Hurtado, Chile, and given its official name, 3I/ATLAS.

The discovery sparked a scientific frenzy as it is only the third interstellar comet, meaning it originates from another solar system, to be discovered.

NASA has determined it "poses no threat to Earth," and that it will remain at a distance of at least 240 million kilometers from the planet.

Harvard astrophysicist Avi Loeb accused NASA of withholding evidence about interstellar comet 3I/ATLAS, during an appearance on “The Joe Rogan Experience.”

Loeb is calling for NASA to release an image taken of the comet by its HiRISE camera aboard the Mars Reconnaissance Orbiter.

“Amazingly, the best image was obtained on Oct. 2, 2025, when 3I/ATLAS came within 30 million kilometers of Mars,” he told Rogan, before adding it “was never released.”

Loeb said he wrote to the principal investigator of HiRISE requesting the image, but received no response.

NASA has not confirmed any such photograph.

A comet is a large, icy body that orbits the Sun. It’s made mostly of ice, dust, and rocky material, sometimes described as a “dirty snowball.”

When a comet approaches the Sun, its ices heat up and vaporize, releasing gas and dust that form a glowing coma (a halo around the nucleus) and sometimes a tail that always points away from the Sun. Comets usually come from the outer regions of the solar system — the Kuiper Belt or the Oort Cloud — and can be visible in the sky for days or weeks as they pass by.

A meteorite, on the other hand, is a solid fragment of rock or metal that has fallen to Earth from space. It starts as a meteoroid, a small piece of debris from a comet or asteroid. When it enters Earth’s atmosphere and burns up due to friction, we see it as a meteor or “shooting star.” If any part of it survives the fiery descent and lands on the ground, that fragment is called a meteorite.

NASA has verified that interstellar comet 3I/ATLAS poses no threat to Earth as it travels through the inner solar system. The agency reports that the comet will reach its closest point to our planet on December 19, 2025, remaining at a safe distance of approximately 1.8 astronomical units—about 170 million miles (270 million kilometers).

Although 3I/ATLAS is following a path near the Sun’s orbit, astronomers stress that its trajectory does not intersect with Earth’s, eliminating any possibility of collision. The confirmation offers reassurance as scientists continue to study this rare visitor from beyond our solar system.

NASA has officially identified 3I/ATLAS as a comet following detailed telescope observations that revealed clear signs of activity—an essential trait that separates comets from asteroids.

Scientists observed an icy core enveloped by a coma, the luminous halo of gas and dust that forms when solar heat vaporizes volatile materials. This outgassing, along with the release of dust, confirms that 3I/ATLAS is composed primarily of frozen compounds, consistent with known comet behavior.

The interstellar object is currently traversing the solar system, offering researchers a rare opportunity to study material from beyond our cosmic neighborhood.

The European Space Agency’s Planetary Defense Office is actively monitoring comet 3I/ATLAS, an interstellar object recently identified as passing through our solar system. In collaboration with observatories worldwide, ESA aims to refine the comet’s trajectory and analyze its composition.

Astronomers are using ground-based telescopes in Hawaii, Chile, and Australia to gather new data, while also conducting a “precovery” search—scanning archival images for earlier sightings that could sharpen orbital predictions.

Although 3I/ATLAS will traverse the inner solar system, ESA confirmed it poses no threat to Earth due to its distant path. The comet will be obscured by the Sun at its closest approach. Still, scientists anticipate renewed visibility in late November, offering a rare second chance to study this ancient galactic traveler.

NASA and ESA’s Hubble Space Telescope have captured striking images of a comet shedding material as it nears the Sun, revealing a bright dust plume on its sunward side and a trailing dust tail behind its nucleus.

As the comet draws closer to the Sun, its frozen gases begin to vaporize, releasing dust and ice into space—a process that gradually causes the comet to lose mass.

Meanwhile, the James Webb Space Telescope (operated by NASA, ESA, and CSA) has identified key compounds in the comet’s coma, or surrounding halo. Among them: carbon dioxide, water, carbon monoxide, carbonyl sulfide, and water ice. These substances are expelled as the comet heats up, offering scientists a rare glimpse into its chemical makeup and the dynamic forces at play during its solar approach.

Physicist Brian Cox has publicly thanked YouTube for removing AI-generated deepfake videos falsely portraying him as endorsing conspiracy theories about comet 3I/ATLAS—but warned the issue is far from resolved.

Cox, a professor at the University of Manchester and a familiar face in science broadcasting, took to social media to condemn the spread of manipulated clips. “AI s**** of me popping up on YouTube,” he wrote, adding that any video showing him supporting UFO theories or calling the comet a spaceship is “fake.”

The controversy centers on comet 3I/ATLAS, discovered in July 2025. As an interstellar object—one of only three ever observed—it doesn’t orbit the Sun and is believed to be over 7 billion years old. Despite its scientific significance, fringe theories have claimed the comet is an alien vessel, prompting deepfakes of scientists like Cox to circulate online.

While YouTube has removed several prominent accounts responsible for the videos, Cox expressed concern about the platform’s slow response and the broader implications. “Doesn’t matter so much if it’s nonsense about a comet,” he tweeted, “but in other areas of science and certainly politics it’s clearly important.”

Cox joins a growing list of celebrities targeted by unauthorized AI content. Keanu Reeves, Tom Hanks, Morgan Freeman, and Jamie Lee Curtis have all spoken out against the misuse of their likenesses in recent months.

Reaffirming the comet’s natural origin, Cox tweeted: “It is entirely natural in origin… a visitor from elsewhere in the galaxy… Isn’t that wonderful enough?”

Scientists are eager to study 3I/ATLAS because it is only the third known interstellar object to pass through our solar system, following ʻOumuamua and 2I/Borisov. Each of these rare visitors offers a unique glimpse into how other planetary systems form and evolve.

By analyzing the light reflected and emitted by 3I/ATLAS, astronomers can determine its chemical composition and compare it with comets that formed around our Sun. This helps reveal whether the same basic ingredients—such as water, carbon compounds, and silicates—exist in distant star systems or if 3I/ATLAS contains unfamiliar materials that hint at a different cosmic environment.

Researchers also hope to understand how interstellar comets survive the harsh conditions of deep space. 3I/ATLAS has likely traveled for millions of years through intense radiation and extreme cold, so its structure and activity near the Sun can show how well such objects preserve their ices and dust over time. By carefully tracking its path, scientists can also attempt to trace its origin, identifying the region of the galaxy it came from and refining models of how comets are ejected from their home systems.

Finally, 3I/ATLAS provides a chance to compare different interstellar objects and explore whether the building blocks of life can move between star systems. ʻOumuamua was rocky and inactive, while 2I/Borisov was icy and comet-like; 3I/ATLAS appears to fall somewhere in between. Studying it could reveal how diverse interstellar material really is and whether organic compounds — the precursors to life — are common throughout the galaxy. In short, 3I/ATLAS is a faint but valuable messenger from beyond our solar system, offering insights into the chemistry and origins of worlds far from our own.

Astronomers around the world have been closely monitoring this interstellar comet since its discovery in mid-2025, and all observations confirm that it continues to follow the same hyperbolic trajectory originally calculated. There’s no evidence of any sudden deviation, shift, or course change.

Like most comets, 3I/ATLAS does experience slight non-gravitational forces caused by outgassing — when sunlight heats the comet’s surface, jets of gas and dust can push it gently. These effects can cause tiny, predictable adjustments to its path, but nothing that would significantly alter its orbit or cause it to head toward Earth. Astronomers routinely model these outgassing effects when refining comet trajectories, and the updates so far have shown only minute corrections well within the expected range.

3I/ATLAS remains on a safe, outbound path through the solar system. Its orbit is hyperbolic, meaning it’s not bound to the Sun and will leave the solar system entirely after passing perihelion (its closest approach to the Sun). NASA’s Jet Propulsion Laboratory (JPL) and the Minor Planet Center continue to track its motion precisely, and the trajectory solutions all confirm it will remain hundreds of millions of kilometers from Earth at its closest.

Comet 3I/ATLAS is expected to make its closest approach to the Sun — its perihelion — around October 29 to 30.

At that time, the comet will pass about 1.4 astronomical units (AU) from the Sun, or roughly 210 million kilometers (130 million miles) away. This distance is a little greater than the orbit of Mars, meaning the comet will not come especially close to the Sun compared to some other comets that dive deep into the inner solar system.

After perihelion, 3I/ATLAS will continue on its outbound path through the solar system, heading back toward interstellar space. Because it’s an interstellar object on a hyperbolic trajectory, it will leave our solar system permanently once it passes perihelion.

According to the live tracker at TheSkyLive, the comet is currently about 344,860,909 km from Earth, passing through the constellation of Virgo.

The comet is on a hyperbolic trajectory and so will not remain in the Solar System indefinitely. At present, it is still inbound, approaching its closest point to the Sun (perihelion) on October 29, at roughly 1.4 AU from the Sun.

3I/ATLAS is not expected hit Earth, with NASA determining it "poses no threat," and that it will remain at a distance of at least 240 million kilometers from the planet - around twice the distance between Earth and the Sun.

3I/ATLAS is on a hyperbolic trajectory, meaning it’s not bound to the Sun by gravity like ordinary comets are. Instead, it’s an interstellar object, passing through our solar system just once before continuing back into deep space. This trajectory ensures that it will not loop around again or come near Earth in the future. The comet reached its closest point to the Sun (perihelion) around October 29–30, 2025, and it will now move steadily away from both the Sun and Earth.

Because of this vast distance and its outbound path, 3I/ATLAS poses no impact threat now or in the foreseeable future. NASA and the Minor Planet Center continue to track its motion, and all available orbital solutions confirm it will remain safely far from Earth.

A comet called 3I/ATLAS is making its closest approach to the sun today (Wednesday October 29)—but is it really an alien spacecraft as one prominent scientist has speculated?

If 3I/ATLAS was a spacecraft, its perihelion—the point on its orbital course that brings it closets to the sun—would be when it would be best suited to change its velocity.

“The perihelion time for 3I/ATLAS was today at 11:47 UT (7:47 Eastern Time) according to the JPL Horizons fit to its trajectory. The uncertainty is only a few minutes,” Avi Loeb, professor of science at Harvard University told Newsweek.

The comet's behavior at perihelion constitutes what Loeb calls the “acid test” to help determine if the interstellar object first detected in July is as it appears—a comet—or something more extraterrestrial.

“If it is a natural comet glued together by weak forces, its heating by 770 watts per square meter may break it up into fragments which evaporate more quickly as a result of their large surface area per unit mass,” Loeb explained.

Read in full from Hannah Millington on Newsweek.

Today, October 29, the comet will reach its closest point to the sun. This point, known as perihelion, usually results in conditions that provide the ideal circumstances for scientists to gain a better understanding and glimpse of the comet's composition.

"Every comet by definition has a close approach to the sun,"  Darryl Seligman, a professor in the physics and astronomy department at Michigan State University, told Newsweek. That point is when the comet has the "most direct sunlight, so it is at its warmest," he added.

This causes different ices to start "activating at different temperatures," meaning "you get the most ices possible," he said.

"Observations of a comet near perihelion are kind of like getting the most bang for your buck—you have the best shot of getting the most holistic view of the comet’s composition because the most possible ices should be active," Seligman added.

Jason Wright, a professor of astronomy and astrophysics and director of the Penn State Extraterrestrial Intelligence Center at Pennsylvania State University, told Newsweek that it will be possible to "catch it again on the way out."

According to NASA, 3I/ATLAS will reappear on the other side of the sun by early December.

While most experts believe 3I/ATLAS is a comet, one scientist, Abraham "Avi" Loeb, a professor of science and director of the Institute for Theory and Computation at Harvard University thinks there could be a 30 to 40 percent chance it is "alien technology."

Loeb's reasoning for this is that he says the comet has displayed eight "abnormalities."

These "abnormalities" include: 3I/ATLAS is significantly larger than both previous interstellar comets found, while moving faster; the fact that it will be "unobservable from Earth" at the point where it is closest to the Sun; "the gas plume around 3I/ATLAS contains much more nickel than iron;" as well as a number of others. 

Loeb has also been voicing his suspicions about the comet's orbit. He said the opportune time for viewing 3I/ATLAS is "during the same period when it is hidden from view to Earth-based telescopes."

He posed the question: "Was this a mere coincidence or a result of orbital design and basic astronautics?"

He also recently said on Mayim Bialik's podcast Bialik Breakdown that: "If you want to take a vacation, take it before that date [October 29]. Because who knows what will happen."

However, other scientists maintain that 3I/ATLAS is a comet. While it has "a few peculiarities," Jason Wright, a professor of astronomy and astrophysics and director of the Penn State Extraterrestrial Intelligence Center at Pennsylvania State University, told Newsweek, "this isn't a big surprise."

He said this was because, firstly, comets in the solar system "have a lot of variation," and secondly, because they are from "another star system, so should have some differences."

"Those differences can help tell us about how other star systems form their planets," he said.

He also said that many comets contain some nickel, as well as most of the elements on the periodic table.

The comet was first discovered on July 1 by the NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) survey telescope in Rio Hurtado, Chile, and given its official name, 3I/ATLAS.

At the time, it was located about 670 million kilometers from Earth. NASA determined it "poses no threat to Earth," and that it will remain at a distance of at least 240 million kilometers from the planet.

Before 3I/ATLAS, there were two other interstellar objects discovered. These were 1I/`Oumuamua and 2I/Borisov, discovered in 2017 and 2019, respectively.

In the scientific community, 3I/ATLAS is widely accepted as a comet. Darryl Seligman, a professor in the physics and astronomy department at Michigan State University, told Newsweek there is "clear-cut evidence of cometary activity–it was and still is behaving entirely in line with solar system comets at large distances."

Seligman said that for some comets that get close to the sun, it is possible to see "nickel vapor because there is nickel in the dust grains coming off of it, and that vaporizes."

This usually happens at "much higher temperatures than 3I/ATLAS was at," he said, but added that this was something "we have seen in solar system comets and also in the last interstellar comet 2I/Borisov."

"This behavior of nickel being seen at far distances where it is too cold for direct nickel sublimation has been seen in solar system comets," he said. "It probably means that the ice structure is complex in 3I/ATLAS, and that nickel was in the ice along with a lot of other species."