A study published this week detailed, for the first time, the arrival patterns of interstellar objects at Terra in the event of a collision. The simulations indicate an average speed of 72 km/s at the moment of impact, a value higher than most meteoroids from Sistema Solar. Researchers used millions of virtual trajectories to map times, directions and regions most likely to fall.
The research considered the relative movement of Sol in Via Láctea and the effect of solar gravity on these bodies. Três already confirmed interstellar objects served as a basis for calibrating the models.
Speeds and energy of impacts
Objects that could reach Terra would have a typical speed of 72 kilometers per second. The Essa mark results from the gravitational focus exerted by the Sol, which diverts slower trajectories and increases the probability of crossing Earth’s orbit.
Faster bodies, above 80 km/s, would be less common among those arriving on the planet. The energy released upon impact would directly depend on this relative speed.
Preferred directions in the sky
The simulations identified two regions of the sky with the greatest flow of objects capable of reaching Terra.
- Direction of the solar apex, where Sol moves in the galaxy.
- Galactic plane, where most of the stars of Via Láctea are concentrated.
These strips concentrate about twice as many potential visitors as random areas. Solar gravity reinforces this direction by bending trajectories that pass close to perihelion.
Seasonality of risks
The risk of collision varies throughout the year. The winter of Hemisfério Norte records the highest number of simulated impacts.
The Terra faces the antapex during this season, which prolongs exposure to the objects focused on by the Sol. Já spring concentrates the events with the highest relative speed.
The most energetic impacts occur as the planet moves toward the solar apex.
Geographic distribution on the surface
The falls would be concentrated in low latitudes. The proximity to Equador favors direct encounters due to the orbital geometry.
There is a slight predominance in Hemisfério Norte. The solar apex is positioned above the equatorial plane, which marginally increases the exposure of this region.
Characteristics of known objects
Three interstellar visitors already detected have striking differences.
1I/‘Oumuamua, discovered in 2017, measured about 80 meters and exhibited no visible coma. 2I/Borisov, identified in 2019, had a core of approximately 400 meters and a coma rich in dust and carbon monoxide.
3I/ATLAS, observed in 2025, recorded a speed of 58 km/s. Todos follow hyperbolic trajectories that confirm origin outside of Sistema Solar.
Simulation methodology
The authors generated 26 billion synthetic objects based on the motion of M dwarf stars.
The model reproduced the observed interstellar flow and applied gravitational perturbations from Sol. The result exclusively mapped the expected distribution of impacts, without estimating absolute frequency.
The combination of gravitational factors and relative movement defines clear arrival patterns, even with extremely low probability.