The Europa Clipper probe, from NASA, crosses in the coming days the possible trajectory of particles from the ionic tail of the interstellar comet 3I/ATLAS.
The event occurs between October 30 and November 6, 2025, without the need for any change in the mission route to Jupiter’s moon Europa.
Scientists predict that the solar wind will carry ions from the comet to the spacecraft’s instruments, allowing the first direct detection of material originating outside the Solar System.
Origin and discovery of the cosmic visitor
The comet 3I/ATLAS was detected on July 1, 2025, by the ATLAS system in Chile.
Its hyperbolic orbit confirms interstellar origin, with a speed of 58 km/s relative to the Sun.
Initial observations captured a coma rich in carbon dioxide. Telescopes like Hubble and James Webb recorded a drop-shaped dust tail. Passage by Mars on October 3 allowed images from orbital probes.
Structure of the ionic tail explained
The ionic tail forms when comet gases ionize near the Sun.
The solar wind pushes these ions for millions of kilometers, opposite to the dust.
Europa Clipper instruments detect plasma and magnetic fields. Analysis distinguishes heavy ions from the comet from solar hydrogen.
Simulations guide the crossing prediction
Researchers used the Tailcatcher software to model the solar wind.
The program tracks particles from the comet’s perihelion, reached on October 29 at 210 million km from the Sun.
The Europa Clipper is positioned at 300 million km, favoring geometric alignment.
Simulations indicate ions at hundreds of km/s reaching the probe.
Detection depends on solar conditions
Factors determine the success of the collection: – Direction and strength of the solar wind. – Post-perihelion activity of 3I/ATLAS. – Activation of the spacecraft sensors.
The probe has a magnetometer and plasma analyzer for precise measurements.
History reinforces the feasibility of predictions
In 2020, Tailcatcher predicted the Solar Orbiter’s hit with another comet’s tail.
Observations confirmed the simulation, validating the current method.
The ESA’s Hera mission crosses a similar region until November 1, but without ideal instruments.
Comparison with previous interstellar objects
1I/‘Oumuamua (2017): No coma detected, elongated shape. 2I/Borisov (2019): Active, but no probe crossing. 3I/ATLAS: Third confirmed, with potential for in situ analysis.
Data from Europa Clipper will reveal unique composition, such as excess CO₂.
Future missions prepare interceptions
The ESA launches Comet Interceptor in 2029 to await new visitors.
Objective focuses on direct flybys of interstellar objects. Coordination with NASA expands the detection network.
The detection of 3I/ATLAS ions marks an advance in interstellar astrochemistry.
Comets preserve materials from billions of years ago, essential to understanding planetary formation.
Europa Clipper transmits data in real time during the opportunity window.