3i/atlas when will it pass earth

3I/ATLAS already made its closest pass by Earth on 19 December 2025, at a distance of about 1.8 astronomical units (roughly 269–270 million km), and it will not come closer than that during this one‑time flyby.

Quick Scoop: 3I/ATLAS and Earth

• 3I/ATLAS is an interstellar comet (the third known interstellar object after ‘Oumuamua and 2I/Borisov).

• It follows a clearly hyperbolic path, meaning it is not bound to the Sun and will leave the Solar System after this passage.

• Its closest approach to Earth (perigee) occurred on 19 December 2025 at about 1.8 AU, around 269–270 million km away.

• That distance is nearly twice the average Earth–Sun distance, so it posed no impact threat to our planet.

Timeline in the Solar System

• Closest approach to the Sun (perihelion): 29 October 2025, at about 1.36 AU from the Sun, between Earth’s and Mars’ orbits.

• Closest approach to Mars: 2–3 October 2025, at roughly 0.19 AU (about 28–29 million km).

• Closest approach to Earth: 19 December 2025, at about 1.8 AU (≈270 million km).

• Close pass by Jupiter: 16 March 2026, at about 0.36 AU (≈54 million km), then it continues outward and eventually exits the heliosphere.

Will it “pass” Earth again?

• 3I/ATLAS is on a one‑time fly‑through; it is not in a repeating orbit like normal comets.

• After the December 2025 closest approach, it moves outward past Jupiter and the outer planets and then into interstellar space, never to return.

In simple terms: its big “Earth moment” was 19 December 2025, it stayed hundreds of millions of kilometers away, and now it’s already on its way back into the dark between the stars.

Information gathered from public forums or data available on the internet and portrayed here.