off you go 3I/ATLAS
Long live Halley!
What we do know:
- 3I/ATLAS is the third confirmed interstellar object (“3 I” = third Interstellar) to pass through our Solar System, after 1I/ʻOumuamua and 2I/Borisov.
- It was discovered on 1 July 2025 by the Asteroid Terrestrial‑impact Last Alert System (ATLAS) survey in Chile.
- Its orbit is hyperbolic (i.e., not bound to the Sun), meaning it came from outside our Solar System and will leave again.
- It poses no threat to Earth: nearest approach is about ~1.8 astronomical units (≈ 270 million km) away.
- Observations show it’s active: it has a coma and tail, and observations pick up outgassing of typical cometary materials (water vapor, carbon dioxide etc.).
Because it’s interstellar, it provides a rare window into material from outside our Solar System, giving scientists hints about how comets or icy bodies in other star systems might behave. It shows strong activity, including jets blasting toward the Sun and complex tail structures. The fact that it remained intact (i.e., didn’t obviously break apart) even after passing reasonably close to the Sun is noteworthy.
“Exactly how large the nucleus is: estimates vary (some suggest <1 km, others a few km) because the coma (the dust/gas cloud around the nucleus) complicates measurements. Some of the fine details of its composition and behaviour are still under study, as is how its chemical makeup compares with that of Solar System comets. There has been speculation (especially by a minority of scientists) about whether its behaviour is fully “natural” or if it might have some unusual origin. For example, some features like jet directions or anti-tails (tail-like features pointing toward the Sun, which are unusual) have stirred discussion.”
I believe 3I/ATLAS is fascinating and valuable scientifically, and likely a natural interstellar comet, but with enough quirks that it will keep astronomers busy for a while. On the positive side, it’s exciting because it literally brings a piece of another star system into our observational reach. The fact that it shows strong activity and remains coherent (didn’t fragment) means it is a robust object and gives us good data.
On the cautious side, some of its behavior: jets, anti-tail, and strong outgassing are more extreme (or atypical) compared to many known Solar System comets. That doesn’t mean “alien probe” or anything, but it means there is more to learn. I’d say for anyone curious about astronomy, this is a “must-watch” object: it will help refine our understanding of comets, interstellar bodies, and how our Solar System interacts with such visitors.
Avi Loeb ranked 3I/ATLAS 4 on the Loeb scale:
Let’s see if it’s even ranked more than 4 one day:
This whole topic reminded me of the Kardashev scale … One of the coolest ideas in astrophysics, it measures a civilization’s level of technological advancement based on how much energy it can use. It was proposed by Russian astrophysicist Nikolai Kardashev in 1964.
Type I Civilization
-Uses all the energy available on its home planet.
-Can control weather, volcanoes, oceans, and climate.
-Harvests all solar power that reaches the planet.
-Has global communication, unlimited clean energy, and full planetary coordination.
(We are NOT EVEN Type I yet.) Humanity is around 0.72 on the scale.
Type II Civilization
-Uses the total energy of its star.
To do that, they would need something like a:
Dyson Sphere / Dyson Swarm
-A huge structure surrounding a star to capture its energy fully.
-Have immense power, basically no energy limit.
-Possibly colonize their star system.
-Manipulate planets, asteroids, maybe build megastructures.
-No known civilizations like this exist yet, but the idea appears in sci-fi and theoretical research (Freeman Dyson, etc.).
Type III Civilization
-Harnesses the energy of an entire galaxy.
-This is extremely advanced, millions or billions of years ahead of humanity.
-Travel between stars easily
-Gather energy from billions of stars
-Potentially shape galactic structure
-Have technology beyond our imagination
-We currently have zero evidence of any Type III civilizations.
The “Unofficial” Types (Some scientists and sci-fi writers expanded the scale.):
Type 0.7 (us): Planet is advanced but not fully using all its energy.
Type IV Civilization: Uses the energy of the entire universe, controlling space-time, dark energy, hyperspace, etc.
This is purely theoretical.
Type V Civilization: Sometimes called a “cosmic godlike civilization,” capable of controlling multiverses. Completely hypothetical.
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Hopefully, we won’t be encountering any hostile above civilization. But then to think about it, if we ever get a visit from an advanced civilization, violence would be an energy-wasting strategy on their end, I think. Like, that’s a primitive, resources-scarcity mindset. Also, distance makes conflict nearly impossible, even with extremely advanced technology. The distances between stars and galaxies are enormous. Crossing them requires a huge time or energy.
Achieving a cooperative and unified mindset is also a thing. Like in the movie Arrival. So it’s more likely a hostile species to self-destruct long before hitting such a high level. It is so tragic that as soon as we talk about UFOs, the first mindset is being hostile. It is indeed showing us that we are for sure(!) not even type I yet…
When viewed against the vast span of Earth’s history, humanity is far too young to be regarded as an advanced civilization.
We are way too invisible compared to the cosmic scale. Humanity is barely a whisper technologically… We emit extremely weak signals. A Type II or III civilization might not even notice us, or simply see us the way we see microbes: interesting but harmless.
I also suggest checking on the Three-Body Problem book series, not the Netflix show, but the books. Based on what we talked about San-Ti/Trisolarans are indeed not a real advanced civilization at all. Even though they are hyper-intelligent, they are also extremely paranoid, aggressive, and expansionist, which makes them intelligent enough but weak at the same time. Because intelligence often means empathy, not cruelty. There should be ethics, consciousness, sustainability, long-term outcomes..
The Trisolarans have advanced communication, biological manipulation, the ability to dehydrate themselves, super technology(sophons, etc.), but(!) they behave with primitive survival instincts, similar to early human warfare. In reality, intelligence + technological endurance requires cooperation, not fear-based aggression.
They are written to be hostile because it makes a good dramatic story. They wouldn’t realistically become a Type II civ. A star system with three suns is extremely unstable. Survival there would be incredibly difficult, but if they reach Type II level, they would not need Earth, not need our resources, not need to invade, not fear us. A type II civilization has nearly infinite energy. Invading a tiny blue planet is pointless. Maybe because they look like this(only Turkish people will understand this joke btw):
Let’s go back to our main topic…
I do still assume this whole thing is an interstellar comet watch. Unusual one, yes, but that’s the cosmos. We don’t know anything yet. Encountering unusual events will only expand our intelligence.
To break down the term interstellar: When something is called interstellar, it means it comes from outside our Solar System, literally, from between the stars.
“Inter” = between + “Stellar” = stars
So interstellar = between the stars
In this case, 3I/ATLAS is an interstellar object, meaning:
-It didn’t form around our Sun.
-It’s just passing through our Solar System on a one-time visit.
-Its path (orbit) is hyperbolic, an open curve that shows it came from far away and will leave again forever.
To compare with our dearest Halley:
Halley’s Comet comes from places inside our Solar System, such as the Kuiper Belt or Oort Cloud. But interstellar comets come from other star systems, drifting in the vast space between them until gravity from our Sun pulls them in temporarily. So 3I/ATLAS is kind of a messenger from another star system, carrying dust and ice that were born around a different sun long, long ago.
Normal comets (like Halley’s) follow elliptical orbits, meaning they loop around the Sun repeatedly, bound by its gravity. Interstellar objects, like 3I/ATLAS (and earlier 1I/ʻOumuamua, 2I/Borisov), have hyperbolic orbits. That shape is open, not closed; it means they enter once and never return.
They come from outside our Solar System. The Sun’s gravity bends their path slightly, but not enough to capture them. After they swing by, they leave forever, continuing their long interstellar journey.
Halley’s Comet, the Famous “Regular Visitor”: Now, Halley’s Comet is the opposite, a periodic comet, which means it belongs to our Solar System. It orbits the Sun every 75–76 years, so humans actually can see it multiple times in a lifetime. The last time it appeared was 1986; the next will be 2061. It’s one of the few comets visible to the naked eye. It comes from the Oort Cloud, a massive icy shell surrounding our Solar System.
When Halley approaches the Sun, the Sun’s heat causes its icy surface to sublimate (turn directly from solid to gas), creating a glowing coma and tail, the beautiful comet shape we know. It’s made of ice, dust, and organic compounds, sometimes called a “dirty snowball.” Unlike 3I/ATLAS, Halley is bound to the Sun, forever part of our Solar System’s family.
Here you can see where Earth’s orbit fits in:
-Earth moves steadily around the Sun at a comfortable distance.
-Halley’s Comet dips much closer to the Sun before looping back out beyond Earth’s orbit; that’s why it’s only visible for a short time every 76 years.
-3I/ATLAS, with its dashed hyperbolic path, just passes through once — entering from deep space, swinging by the Sun, and heading back out forever into the interstellar void.
Off you go 3I/ATLAS! Long live Halley!
…again and again and again…
