Slide the selector to compare all three confirmed interstellar objects side by side - 1I/'Oumuamua, 2I/Borisov, and 3I/ATLAS - each drawn with a schematic path curve sized by its real orbital eccentricity and a body scaled to its real published size and coma activity.
Drag to orbit and scroll or pinch to zoom on the scene above. The three path curves show relative orbital extremity only - they are not drawn to true AU distance or time scale.
For 'Oumuamua's tumbling motion and its trajectory-anomaly story in full depth, see the 'Oumuamua 3D Explorer. For 2I/Borisov's coma-composition contrast against a typical bound solar-system comet, see the 2I/Borisov Interstellar Comet 3D Explorer.
3I/ATLAS Interstellar Object 3D Explorer
Slide the selector in this browser explorer to compare 3I/ATLAS, the third confirmed interstellar object, against 'Oumuamua and Borisov, the two objects discovered before it, using each object's real published orbit, size, and coma-activity figures.
3I/ATLAS was discovered on 1 July 2025 by the NASA-funded ATLAS survey telescope in Rio Hurtado, Chile, becoming the third confirmed interstellar object after 1I/'Oumuamua (2017) and 2I/Borisov (2019). Its orbital eccentricity is about 6.1 - the most extreme (least gravitationally bound) path of the three, compared with about 1.2 for 'Oumuamua and about 3.36 for Borisov - with an orbital inclination of about 175 degrees, a near-polar, retrograde path. It reached perihelion, its closest approach to the Sun, at about 1.36 AU (roughly 1.4 AU) on 30 October 2025, moving at about 221,000 km/h at discovery and increasing to about 246,000 km/h at perihelion. NASA's official nucleus-size estimate is a wide range - a diameter of not less than 440 meters and not greater than 5.6 kilometers - while one modeling study separately estimates an effective radius around 10 km assuming an asteroid-like albedo; the two approaches disagree, which is disclosed here rather than picked as a single settled number. 3I/ATLAS is confirmed active: a 2026 study measured a peak post-perihelion water production rate of about 4x10^28 molecules per second with stable, outburst-free outgassing and a minimum active fraction of about 30 percent. NASA confirms it never comes closer to Earth than about 1.8 AU (270 million km) - there is no impact risk. A separate 2026 research team's kinematic analysis suggests, from its orbit, that 3I/ATLAS may be a relic from the galaxy's "cosmic noon" star-forming era roughly 9 to 13 billion years ago - a genuinely fascinating possibility, but one specific team's analysis rather than a settled consensus figure.
The other two known interstellar objects tell a different story each. 1I/'Oumuamua showed no coma or outgassing at all - NASA calls it "completely inert" - despite a real, statistically significant trajectory anomaly that remains only partly explained. 2I/Borisov actively outgassed a carbon-monoxide-rich coma unlike any typical solar-system comet. 3I/ATLAS is also confirmed active, with its own distinct water-driven outgassing signature. Seeing all three side by side, with their real orbital eccentricities driving how open each schematic path curve looks, makes the escalating extremity across the three discoveries concrete rather than abstract.
- Selector (0-2) swaps the highlighted object between 1I/'Oumuamua, 2I/Borisov, and 3I/ATLAS, redrawing the facts panel with that object's real published figures
- Three schematic path curves show relative orbital extremity, with curvature mapped from each object's real eccentricity - illustrative shape only, not to true AU distance or time scale
- 'Oumuamua renders as an elongated, coma-less capsule matching its real cited ~10:1 shape; Borisov and 3I/ATLAS render as comet nuclei with particle-cloud comas sized by their real coma activity
- A comparison table ranks all three objects' discovery year, orbital eccentricity, and coma status side by side, with the active object highlighted
- Drag to orbit, scroll or pinch to zoom
- Runs fully in the browser with the vendored three.js engine - no account, no upload
| Object | Discovered | Eccentricity | Perihelion | Coma / outgassing |
|---|---|---|---|---|
| 1I/'Oumuamua | 19 Oct 2017 | about 1.2 | about 0.25 AU | None detected |
| 2I/Borisov | 30 Aug 2019 | about 3.36 | about 2.01 AU | Yes, CO-rich |
| 3I/ATLAS | 1 Jul 2025 | about 6.1 | about 1.36 AU | Yes, stable water outgassing |
For 'Oumuamua's tumbling motion and its trajectory-anomaly story in full depth, open the 'Oumuamua 3D Explorer. For 2I/Borisov's coma-composition contrast against a typical bound solar-system comet, see the 2I/Borisov Interstellar Comet 3D Explorer.
Everything renders on your device with WebGL. The 3D engine loads once (about 0.7 MB) and is cached.
This is an educational approximation - the three path curves are schematic, with curvature mapped from each object's real eccentricity rather than drawn to true AU distance or time scale; nuclei are stylized shapes (an elongated capsule or scaled "potato" spheres), not scanned models; and comas are radially-expanding particle clouds, not directional tails shaped by solar wind and radiation pressure.
Frequently Asked Questions
What is 3I/ATLAS?
3I/ATLAS is the third confirmed interstellar object, discovered on 1 July 2025 by the NASA-funded ATLAS survey telescope in Rio Hurtado, Chile. It follows 1I/'Oumuamua (2017) and 2I/Borisov (2019) as only the third object ever confirmed to have come from outside the solar system.
How extreme is 3I/ATLAS's orbit compared to the other two?
3I/ATLAS has an orbital eccentricity of about 6.1, versus about 1.2 for 'Oumuamua and about 3.36 for Borisov - making it the most extreme, least gravitationally bound path of any known interstellar object. Its inclination is about 175 degrees, a near-polar, retrograde path.
How big is 3I/ATLAS?
NASA's official range is a diameter of not less than 440 meters and not greater than 5.6 kilometers - a wide uncertainty band. One modeling study separately estimates an effective radius around 10 km assuming an asteroid-like albedo. The two approaches disagree, which this page discloses rather than picking one settled number.
Does 3I/ATLAS have a coma, like a comet?
Yes. A 2026 study measured a peak post-perihelion water production rate of about 4x10^28 molecules per second, with stable, outburst-free activity and a minimum active fraction of about 30 percent. This contrasts with 'Oumuamua, which showed no detected coma at all.
Is 3I/ATLAS dangerous to Earth?
No. NASA confirms 3I/ATLAS never comes closer to Earth than about 1.8 AU (270 million km) - there is no impact risk.
Could 3I/ATLAS really be billions of years older than the solar system?
One 2026 research team's kinematic analysis suggests, from its orbit, that 3I/ATLAS may be a relic from the galaxy's "cosmic noon" star-forming era roughly 9 to 13 billion years ago. This is a genuinely fascinating possibility raised by one specific study, not yet a settled consensus figure.
How does 3I/ATLAS compare to 'Oumuamua and Borisov overall?
All three are confirmed interstellar visitors, but each tells a different story: 'Oumuamua showed no coma and a real, still-partly-unexplained trajectory anomaly; Borisov actively outgassed a carbon-monoxide-rich coma; 3I/ATLAS has the most extreme orbit of the three and its own confirmed water-driven outgassing.
Is the on-screen scene to true scale?
No. The three path curves are schematic, with curvature mapped from each object's real eccentricity rather than drawn to true AU distance or time scale. Nuclei are stylized shapes (an elongated capsule or scaled "potato" spheres), not scanned models, and comas are drawn as radially-expanding particle clouds rather than directional solar-wind tails.
Where do these figures come from?
NASA Science's 3I/ATLAS Facts and FAQs page, the Chandler et al. 2025 discovery paper (Monthly Notices of the Royal Astronomical Society: Letters), a 2026 preprint on 3I/ATLAS's possible galactic thick-disk origin, a 2026 preprint on its water production rate, and this site's own verified truth sources for 'Oumuamua and Borisov (themselves cited to NASA, Wikipedia, and peer-reviewed Nature/Nature Astronomy/ApJL papers).