Comet 3I/ATLAS Today: NASA, UN Drill and Alien‑Probe Claims Explained (Nov. 29, 2025)

The interstellar comet 3I/ATLAS is now sweeping back out of the inner solar system, but the news cycle around it is only getting hotter. On November 29, 2025, new headlines are mixing hard data from NASA and the UN with high‑profile speculation from physicists Avi Loeb and Michio Kaku about “energy boosts,” “controlled emissions” and even possible alien probes.

Here’s a clear, fact‑checked look at what’s actually new today, how comet 3I/ATLAS is behaving, and why scientists say it’s extraordinary but not a threat.

Quick facts about comet 3I/ATLAS

What it is: The third confirmed interstellar object ever seen, after 1I/ʻOumuamua (2017) and 2I/Borisov (2019). It’s also cataloged as C/2025 N1 (ATLAS). TS2 Tech+1
Origin: Its strongly hyperbolic orbit (eccentricity ≈ 6.1) proves it came from outside the solar system and will never return. TS2 Tech+1
Discovery: First spotted on July 1, 2025 by the ATLAS survey telescope in Chile. ^[1]
Closest to the Sun (perihelion): Around Oct. 29–30, 2025, at ~1.36–1.4 AU (between Earth and Mars), moving at roughly 250,000 km/h (155,000 mph). ^[2]
Closest to Earth: Due Dec. 19, 2025, at about 1.8 AU (~270 million km / ~170 million miles) – very far away. ^[3]
Size: Hubble and other data suggest a nucleus under ~5.6 km across, and possibly under 1 km. ^[4]
Composition: Unusually rich in carbon dioxide (CO₂) and relatively poor in water compared with typical comets, but still ejecting familiar gases like cyanide and nickel vapour. TS2 Tech+1
Age: Modelling suggests it may be up to ~7 billion years old, potentially older than the Sun – making it a candidate for the oldest comet ever observed. ^[5]
Threat level: Zero, per NASA and ESA. Its path never brings it remotely close enough to pose impact danger. ^[6]

What’s new about 3I/ATLAS today (Nov. 29, 2025)?

Several threads have come together in the last 24–48 hours:

UN planetary‑defence drill using 3I/ATLAS is now underway.
New commentary from physicist Michio Kaku highlights a tiny “extra acceleration” as a possible alien clue. ^[7]
A detailed feature on “alien probe or cosmic trick?” walks readers through Avi Loeb’s claims and the mainstream rebuttals. ^[8]
Fresh round‑ups stress NASA’s verdict: 3I/ATLAS behaves like a comet, despite its quirks. ^[9]
Live tracking shows where the comet is this morning and how bright it appears in backyard telescopes. ^[10]

Let’s unpack each of those.

1. UN planetary‑defence drill: a “live‑fire” test, not a crisis

The United Nations Office for Outer Space Affairs (UNOOSA) and the International Asteroid Warning Network (IAWN) have officially designated comet 3I/ATLAS as the target of their latest planetary‑defence observing exercise, which began Nov. 27, 2025 and runs to Jan. 27, 2026. ^[11]

Key points:

It’s the eighth global observing drill of this kind since 2017.
The exercise focuses on precision tracking, orbit refinement and coordinated communication between observatories worldwide. ^[12]
Official documents stress that 3I/ATLAS poses no impact risk; its closest approach to Earth stays around 1.8–2.0 AU – far beyond any danger zone. ^[13]

In other words, this is a dress rehearsal using a safe but scientifically rich target, not a sign that Earth is under threat from the comet.

2. NASA doubles down: “3I/ATLAS is a comet, not alien tech”

Over the past ten days, NASA has staged a series of briefings and content drops now being widely quoted in today’s coverage:

A multi‑mission image release on Nov. 19 showcased views from Hubble, JWST, Mars orbiters, heliophysics missions like SOHO, STEREO and PUNCH, and deep‑space probes such as Lucy and Psyche. ^[14]
In a press conference summarized by Space.com and WIRED, NASA officials emphasised two core conclusions:
1. No technosignatures – nothing in the data looks artificial.
2. No threat to Earth – the trajectory keeps the comet comfortably distant from all planets, including Earth and Jupiter. ^[15]

As NASA Associate Administrator Amit Kshatriya put it, “3I/ATLAS is a comet” – a weird, informative one, but still a natural body. ^[16]

Meanwhile, a Wired feature on NASA’s latest image set leans into the “magic” of the object’s differences: the CO₂‑rich coma, faint hydrogen halo and delicate tail all hint at formation in a very cold, distant region of another star system, perhaps predating our own Sun. ^[17]

3. Radio signal detected – and why it argues for a natural comet

Headlines about a “radio signal from 3I/ATLAS” sound tailor‑made for alien speculation, but the underlying science is surprisingly mundane – and powerfully confirming.

Earlier this month, the MeerKAT radio array in South Africa detected absorption lines at 1665 and 1667 MHz from the direction of the comet. ^[18]

What that means:

The lines are due to hydroxyl radicals (OH) – fragments of water molecules broken apart by sunlight. ^[19]
Those OH signatures are textbook comet behaviour, seen in other comets whose water vapour is being dissociated near the Sun. ^[20]

Both WIRED and Live Science frame the detection as more evidence that 3I/ATLAS is an active, outgassing comet, not a beacon. ^[21]

Even Avi Loeb, whose blog helped popularise alien‑craft speculation, acknowledges that no narrowband, message‑like transmissions have been detected – only this natural OH signature. ^[22]

4. New “energy boost” and alien‑probe claims – what’s behind them?

Michio Kaku’s “boost of energy”

Today one of the big viral items is an International Business Times piece noting that physicist Michio Kaku, who earlier called alien‑ship claims “garbage,” is now drawing attention to a small extra acceleration measured in late November. ^[23]

According to that reporting:

Kaku had previously said that if 3I/ATLAS showed a clear non‑gravitational acceleration after perihelion, it would be worth considering exotic explanations.
New orbit fits around Nov. 24 reportedly show an additional acceleration of about 4 × 10⁻⁷ AU/day² – an extremely tiny push, but statistically significant in precision tracking. ^[24]

Importantly:

Such small non‑gravitational terms are normal for active comets, whose jets act like weak thrusters.
NASA and ESA already model 3I/ATLAS’s orbit with built‑in outgassing forces and still get a safe, hyperbolic escape trajectory fully compatible with a natural comet. ^[25]

Kaku’s updated comments are best read as a “keep watching, don’t panic” stance – not a declaration that aliens have been found.

Avi Loeb’s “controlled emissions” and Jupiter‑satellite idea

Separately, Avi Loeb has argued that 3I/ATLAS’s path and brightness changes might hint at deliberate control. In coverage this week and today, his main talking points include: TS2 Tech+2New York Post+2

A very thin, straight tail in late‑November photographs, dubbed “beam‑like” in some articles. ^[26]
Subtle non‑gravitational accelerations near perihelion.
A predicted close pass by Jupiter on March 16, 2026, at roughly Jupiter’s Hill radius – the boundary of its gravitational influence – which he suggests could be ideal for “dropping off probes.” TS2 Tech+1

However, mainstream comet and dynamics experts have been systematically pushing back:

A detailed breakdown by astronomer Jason Wright shows that Loeb’s “anomalies” (tail shape, alignment, brightness changes) all fit within known comet physics once you factor in high speed, CO₂‑rich ices and viewing geometry. ^[27]
The Economic Times and other outlets highlight that extreme image processing and perspective effects can make a normal tail look like an unnaturally straight “beam.” ^[28]
NASA’s trajectory solutions still show a smooth, outgassing‑driven path, not the fine‑tuned course corrections that an engineered spacecraft would likely require. ^[29]

A new longform piece today on SSBCrack News essentially sums up the situation: 3I/ATLAS is weird, but every “anomaly” proposed so far has a plausible natural explanation, while the evidence for technology remains speculative at best. ^[30]

5. Where is comet 3I/ATLAS right now – and can you see it?

Live ephemeris data compiled by TheSkyLive and other trackers give a snapshot for Nov. 29, 2025: ^[31]

Constellation: Virgo, in the pre‑dawn sky for mid‑northern latitudes.
Distance from Earth: ~288 million km (~179 million miles), or about 1.93 AU. ^[32]
Brightness: Recent observations put it around magnitude 10–11 – far too faint for the naked eye, but reachable with a moderate amateur telescope under dark skies. ^[33]
Typical schedule (example: Greenwich, UK):
- Rises around 1:40 a.m. local time
- Highest in the sky near 7:30 a.m.
- Sets into the daytime sky around early afternoon ^[34]

Because it’s receding from both the Sun and Earth, 3I/ATLAS will slowly fade over the next several weeks after its Dec. 19 Earth‑distance minimum.

6. How strange is 3I/ATLAS scientifically?

Even if you ignore the alien‑probe talk, comet 3I/ATLAS is genuinely unusual, which is why astronomers are so excited.

Interstellar origins and extreme orbit

Its hyperbolic eccentricity (~6.1) is much higher than typical long‑period comets, underscoring its status as a true interstellar visitor. TS2 Tech+1
Approaching from near the Galactic “frontier” region of the Milky Way and then whipping past the Sun at ~250,000 km/h, it will eventually head back out toward the stars, never to return. ^[35]

Odd chemistry: CO₂‑rich, water‑poor

Spectroscopy by JWST, Hubble, ground‑based observatories and Mars‑orbiting spacecraft shows that 3I/ATLAS’s coma is dominated by carbon dioxide, with relatively less water than many solar‑system comets, plus molecules like CO, CN and traces of metals such as nickel. ^[36]

That suggests:

It likely formed in a very cold, distant zone of its home star system, where CO₂ would freeze out in abundance.
Its material may have been exposed to cosmic rays and interstellar space for billions of years before entering our neighbourhood. ^[37]

Activity and “weird” tail

3I/ATLAS checks all the classic comet boxes—coma, tail, outgassing jets, and now OH radio signatures—yet with some exotic twists:

It has shown a highly collimated, almost laser‑thin tail in recent astrophotography, a configuration some commentators say “breaks the rules of comet physics.” ^[38]
NASA images from Mars orbitors and heliophysics missions reveal a dynamic coma with complex jets that likely drive the small non‑gravitational accelerations seen in orbit fits. ^[39]

Most comet specialists view this as a natural outcome of unusual ices, high speed and viewing angle, not a sign of artificial steering.

7. Don’t confuse 3I/ATLAS with the “other ATLAS” that exploded

Adding to public confusion, there is another, completely unrelated comet in the news: C/2025 K1 (ATLAS) – often called the “other ATLAS”.

C/2025 K1 is a solar‑system comet from the Oort Cloud, discovered earlier this year by the same ATLAS survey.
It developed a striking golden glow before dramatically breaking into several fragments after its own close solar pass in October. ^[40]

Fresh images published this week by both Live Science and the Virtual Telescope Project show new fragments still drifting apart as of Nov. 29. ^[41]

Crucially:

C/2025 K1 (ATLAS) and 3I/ATLAS are different objects with different orbits and histories.
They just share the “ATLAS” name because the same automated survey discovered them.

So when you see talk of an ATLAS comet exploding, that’s C/2025 K1, not the interstellar visitor 3I/ATLAS.

8. Why 3I/ATLAS matters for science and planetary defence

A rare window into other star systems

Because 3I/ATLAS was discovered inbound and monitored across perihelion, it offers:

A time‑resolved look at how an interstellar body heats up and outgasses.
A chemical laboratory for ices formed around another star, potentially older and colder than our own protoplanetary disc. ^[42]

That’s why NASA, ESA and ground‑based networks have thrown more than 20 spacecraft and telescopes at it, from JWST to Mars orbiters and heliophysics monitors. ^[43]

The data will feed into:

Models of planet formation in other systems.
Predictions of how often interstellar objects pass through our neighbourhood.
Strategies for future fly‑by missions that could meet the next 1I/ʻOumuamua‑style visitor. ^[44]

A real‑world planetary‑defence test case

Using 3I/ATLAS as a UN‑endorsed test object lets agencies practice: ^[45]

Rapid global orbit refinement with data from Earth and Mars.
Coordinated public communication when an object captures viral attention.
Cross‑agency collaboration between NASA’s Planetary Defense Office, ESA’s NEO Coordination Centre and the UN – the same ecosystem that would respond if a truly hazardous asteroid were ever found.

In short: even if 3I/ATLAS is “just” a comet, it’s a dress rehearsal for the day the threat is real.

9. Key upcoming dates for comet 3I/ATLAS

Dec. 19, 2025 – Closest to Earth
- Distance: ~1.8 AU (~270 million km).
- Best window for coordinated observations and public telescope livestreams. ^[46]
Late Dec 2025 – early 2026 – Fading but still monitored
- Comet continues outward, gradually dimming but still tracked by professional observatories.
Mar. 16, 2026 – Closest approach to Jupiter
- Passes near Jupiter’s Hill sphere, a key focus of both scientific interest and Avi Loeb’s “probe‑release” speculation. ^[47]
Through Jan. 27, 2026 – UN planetary‑defence exercise window
- Global telescopes contribute astrometry and photometry as part of the IAWN drill. ^[48]

After that, 3I/ATLAS will fade into deep space, taking its secrets with it – apart from the treasure trove of data left in our archives.

10. FAQ: Short answers to big 3I/ATLAS questions

Is comet 3I/ATLAS an alien spacecraft?
There is no evidence that 3I/ATLAS is artificial. NASA, ESA and most comet researchers conclude it’s a natural interstellar comet whose oddities can be explained by unusual ices, geometry and high speed. Speculative hypotheses about probes or engines remain just that: speculation. ^[49]

Will comet 3I/ATLAS hit Earth or any planet?
No. All current orbit solutions show a wide miss: ~1.8 AU from Earth in December, and no dangerously close encounters with other planets. ^[50]

Why are people talking about “energy boosts” and “controlled emissions”?
Because the comet shows small non‑gravitational accelerations and unusual tail structure, which some commentators interpret as potentially artificial. But tiny accelerations and complex tails are common in active comets, and the magnitudes seen here fit within natural models. ^[51]

What makes 3I/ATLAS different from past comets?

It’s interstellar, not from our Oort Cloud.
It likely formed in an extremely cold, distant environment, and may be older than the Sun.
Its coma is unusually CO₂‑rich and water‑poor.
It has been watched by an unprecedented fleet of spacecraft, from Mars orbitors to heliophysics probes and space telescopes. ^[52]

Is 3I/ATLAS the same as the golden comet that broke apart?
No. That was C/2025 K1 (ATLAS), the “other ATLAS,” a separate comet that recently exploded into fragments after perihelion. 3I/ATLAS is intact and on a safe, outbound trajectory. ^[53]