Lead: NASA is poised to release exceptionally sharp images of interstellar comet 3I/ATLAS taken by the HiRISE camera on the Mars Reconnaissance Orbiter following the U.S. government shutdown’s end. Meanwhile, China’s Shenzhou-21 astronauts remain aboard the Tiangong space station after the Shenzhou-20 crew returned in their capsule; an uncrewed replacement ship is being prepared. In parallel, Yann LeCun, a prominent AI researcher, has publicly described large language models (LLMs) as a “dead end,” reigniting debate about AI research directions and limits.
Key Takeaways
- HiRISE aboard NASA’s Mars Reconnaissance Orbiter captured images of comet 3I/ATLAS when it passed Mars in early October; the full set is pending official release.
- 3I/ATLAS is estimated at roughly 7 miles (11 km) across and traveling near 130,000 mph (210,000 km/h); it passed perihelion about two weeks before Nov. 17, 2025.
- Scientists estimate the comet could be older than 7 billion years, potentially predating the Sun by more than 3 billion years, though its precise galactic origin is unresolved.
- Shenzhou-21 crew remain on Tiangong after Shenzhou-20 returned; Chinese authorities say an uncrewed replacement spacecraft is being readied to restore normal rotation of crewed missions.
- Yann LeCun has publicly argued that current LLM architectures are a dead end for achieving general intelligence, prompting responses across industry and academia.
- HiRISE images are reported to rival or exceed Hubble’s July images of the comet in resolution, a claim that will be testable once NASA releases the data.
- Converging observations (optical, radio) have shown comet-like signatures from 3I/ATLAS, which fuels scientific curiosity and public speculation alike.
Background
Comet 3I/ATLAS was discovered in early July 2025 and is catalogued as the third confirmed interstellar object observed passing through our solar system. Interstellar visitors are rare—only a handful have been identified—so each offers a unique opportunity to study material formed around other stars. Because such objects have spent billions of years exposed to cosmic rays and interstellar conditions, their surfaces and composition can be heavily altered, complicating efforts to trace their exact origin within the Milky Way.
The Mars Reconnaissance Orbiter (MRO) has orbited Mars since 2006 and carries the High Resolution Imaging Science Experiment (HiRISE), a camera designed to resolve fine details on the Martian surface. In early October 2025, HiRISE opportunistically imaged 3I/ATLAS as it passed near Mars, producing frames that sources say may surpass the quality of Hubble’s July observations. Independent ground- and space-based facilities have supplemented the dataset, generating a broader multiwavelength view of the comet.
Separately, China’s crewed space program has maintained continuous habitation aboard the Tiangong modular station. Shenzhou missions rotate crews and return them in short-duration capsules; the return of Shenzhou-20 left Shenzhou-21 crewmembers still aboard Tiangong while a follow-up uncrewed vehicle is prepared. Chinese mission planners emphasize routine logistics and safety while communications and flight hardware checks proceed.
Main Event
NASA sources report that the HiRISE images were taken during 3I/ATLAS’s passage by Mars in early October and are now cleared for release following the end of the U.S. government shutdown. The images have not yet been publicly posted at the time of this report, but internal analysis suggests finer structural detail in the comet’s coma and tail than previously available. If confirmed, the higher spatial resolution will help researchers assess grain size distribution, activity regions on the nucleus, and interaction with solar wind at closer scales.
Observational teams estimate the nucleus of 3I/ATLAS to be about 11 kilometers in diameter and traveling at roughly 210,000 kilometers per hour relative to the Sun. It reached perihelion approximately two weeks before Nov. 17, 2025, and is projected to make its closest approach to Earth on Dec. 19, 2025. Those timing details have focused international telescope time and radio observatory scheduling to capture the comet’s changing activity as it moves outward from the Sun.
In human spaceflight news, after Shenzhou-20 returned its crew in the standard reentry capsule, Shenzhou-21 astronauts remained on Tiangong because the next crewed return vehicle was not immediately available. Chinese mission control indicated that an uncrewed replacement spacecraft is being prepared to dock and support the station’s crew rotation plans. Officials have emphasized crew safety and the routine nature of sending an automated ship when needed.
On the technology front, Yann LeCun — long influential in machine-learning research — stated that large language models are a “dead end” for achieving true artificial general intelligence, arguing for alternative architectures and principles. The comment has prompted responses from researchers who both agree that new approaches are needed and those who defend incremental advances with LLMs combined with other systems.
Analysis & Implications
The pending release of HiRISE frames could materially improve our understanding of 3I/ATLAS because spatial resolution directly affects what physical processes we can observe. Higher-resolution images may reveal localized jets on the nucleus, fragmentation events, or fine-scale tail morphology that indicate the size and composition of ejected particles. Those details feed into models of volatile content and surface processing, informing theories about planetesimal formation in other stellar systems.
Pinpointing the comet’s galactic provenance — whether from the Milky Way’s thin disk, thick disk or another subpopulation — remains challenging. Orbital reconstruction backtraces the path but uncertainties in past perturbations and the effects of long-term cosmic-ray exposure on surface reflectance complicate interpretation. A clearer physical and chemical profile can narrow formation scenarios and offer constraints on conditions around the comet’s birth environment more than 7 billion years ago.
For China’s human spaceflight program, the temporary extension of the Shenzhou-21 mission aboard Tiangong is operationally manageable but underscores the logistical tightness of short-duration capsule rotations. Reliance on an uncrewed replacement craft is a standard contingency, yet it emphasizes the importance of redundancy and scheduling flexibility as lunar and orbital ambitions grow. International partners and observers will watch the timeline for the automated vehicle’s launch and docking as an indicator of program robustness.
LeCun’s critique of LLMs feeds into a larger debate about AI research strategy. If widely accepted, such a view could shift funding and effort toward hybrid models that integrate learning with reasoning, world models, embodied agents, or novel algorithmic frameworks. If not, continued iterative improvements to LLMs and their integration into broader systems may still yield substantial applied benefits even without delivering general intelligence.
Comparison & Data
| Parameter | Value |
|---|---|
| Estimated nucleus diameter | ~7 miles (11 km) |
| Peak speed | ~130,000 mph (210,000 km/h) |
| Perihelion | ~two weeks before Nov. 17, 2025 |
| Closest approach to Earth | Dec. 19, 2025 (projected) |
The table condenses the main physical and temporal parameters confirmed by telescope tracking and orbital solutions. While the size and speed figures come from multi-observatory measurements, the exact surface properties and internal structure require the higher-resolution imaging and follow-up spectroscopy to resolve composition and activity mechanisms.
Reactions & Quotes
“Marvelous new image of interstellar Comet 3I/ATLAS…captures intricate structure in its tail(s).”
Satoru Murata (amateur astrophotographer, tweet)
Murata’s ground-based photograph highlights fine tail structure visible to skilled observers and helps coordinate professional follow-up observations.
“Large language models are a dead end for real AI advancement,”
Yann LeCun (AI researcher)
LeCun’s concise formulation summarizes his broader critique and catalyzes debate about research priorities across industry and academia.
“An uncrewed vehicle is being readied to support crew rotation,”
China space mission control (official update)
Chinese authorities framed the delay as a logistical adjustment and emphasized that crew safety remains the primary concern while the automated ship prepares for launch.
Unconfirmed
- Claims that HiRISE images definitively exceed Hubble’s July pictures in scientific utility remain to be verified when NASA releases the full dataset.
- The comet’s precise birth location in the Milky Way (thin disk vs. thick disk) is unresolved and subject to large uncertainties.
- Conjecture that 3I/ATLAS could be an artificial probe lacks evidence and remains speculative.
Bottom Line
The imminent public release of HiRISE images of 3I/ATLAS could materially sharpen our understanding of an exceptionally old interstellar visitor, where higher spatial detail will refine models of its activity and composition. The comet’s size (~11 km), speed (~210,000 km/h), and projected close approach to Earth on Dec. 19, 2025, make it a priority target for observatories worldwide.
China’s temporary extension of the Shenzhou-21 stay aboard Tiangong underscores routine operational challenges in human spaceflight and the value of uncrewed logistics. Meanwhile, Yann LeCun’s critique of large language models has reignited strategic discussions in AI research—decisions in the coming months may influence funding and the balance between incremental engineering and exploratory new paradigms.