New Update – 3I/Atlas Keeps Getting Bigger and Brighter As It Closes on Sun
3I/Atlas: Unveiling the Mysteries of the Third Interstellar Visitor
Tonight, we explore three new updates about 3I/Atlas, possibly our best chance yet to clearly observe the third interstellar object ever detected passing through our solar system. 3I/Atlas is no ordinary comet. It is hurtling toward Earth at an astonishing 130,000 mph (210,000 km/h), growing larger, brighter, changing color, and shedding a gas cloud wider than Jupiter itself.
What’s strange is that its orbit shows no signs of the non-gravitational forces typical of comets, as if the object is made of something far denser — perhaps even extraterrestrial. A principal investigator claimed he couldn’t release the information due to a “government shutdown,” but many scientists suspect that’s just an excuse. Meanwhile, 3I/Atlas is racing toward Mars at 60 km/s and will soon disappear behind the Sun, leaving only a handful of orbiters to witness its most dangerous and mysterious phase.
Initial Discovery
On the night of July 1, 2025, robotic telescopes scanning the southern sky detected an unusual streak of light in the constellation Libra. These telescopes belong to ATLAS (Asteroid Terrestrial-impact Last Alert System), whose main task is to monitor potentially hazardous space objects.
Within hours, astronomers realized that the object was moving far too fast on a hyperbolic trajectory, meaning it was not gravitationally bound to the Sun. Calculations confirmed that it came from another star system and was just passing through our solar neighborhood. NASA officially named it 3I/Atlas, marking it as the third interstellar visitor, after ‘Oumuamua (2017) and 2I/Borisov (2019).
While ‘Oumuamua appeared like a strange elongated debris and 2I/Borisov resembled a typical comet, 3I/Atlas is a hybrid object, defying all established models.
Rapid Brightening and Strange Gas
Initially, 3I/Atlas was extremely faint at magnitude 17, only visible through professional telescopes. Early models predicted a slow increase in brightness. By early September 2025, it had brightened to magnitude 12–14, about 40 times brighter in just a few months — far beyond predictions.
Amateur astronomers also began reporting observations, which are crucial for tracking rapid changes. Meanwhile, the James Webb Space Telescope measured the comet’s coma, which had expanded to 350,000 km, more than twice the width of Jupiter. Even more surprising, the coma was overwhelmingly composed of carbon dioxide, with a CO₂:H₂O ratio of 8:1, completely opposite to typical comets, which release more water than CO₂.
The Green Glow Mystery
On September 7, 2025, observers noticed the coma suddenly turned vibrant green. Normally, a green comet indicates the presence of diatomic carbon (C₂), but in this case, no C₂ or other usual molecules were detected.
Possible explanations include:
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Newly exposed ices releasing different chemical species.
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Dust scattering sunlight in a way that emphasizes green wavelengths.
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Exotic chemical reactions in the CO₂-rich environment producing unknown molecules.
Solar Impact
On September 19, 2025, a coronal mass ejection (CME) was directed at 3I/Atlas. CME impacts are violent, capable of stripping material from a comet’s nucleus or even fragmenting it. Observations revealed that 3I/Atlas survived, though its tail and coma were disrupted, likely releasing fresh material and creating new vents. This provided valuable data on how interstellar objects withstand harsh solar conditions.
Orbit Anomalies
Despite shedding large amounts of material, 3I/Atlas shows no non-gravitational acceleration, a phenomenon normally caused by outgassing jets. Explanations include:
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Extremely symmetrical gas ejection from a nearly perfect spherical nucleus, or
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A dense or massive core, possibly composed of rock or metal, resisting the tiny forces from outgassing.
Mars Encounter
In early October 2025, 3I/Atlas will pass about 30 million km from Mars — safe, but close enough for Mars orbiters like Mars Express and ExoMars Trace Gas Orbiter to observe in detail. These spacecraft can provide direct measurements of the nucleus, gas production rates, dust properties, and solar wind interactions, impossible to achieve from Earth due to the Sun’s glare.
Conclusion
The journey of 3I/Atlas is a living experiment on interstellar objects, from its unusual orbit, extreme CO₂ dominance, and unexpected green glow to its resilience against solar storms. It raises important questions about its origin, structure, and formation conditions in another star system. Observations during perihelion at the end of October will be crucial in revealing its true nature and may expand our understanding of the diversity of interstellar bodies in the galaxy.
