According to the latest research by American and French astronomers, a passing star could potentially disrupt the orbits of planets in the solar system, posing risks of Earth either falling into the sun, being destroyed in a collision, or even being ejected from the solar system in the next 5 billion years.
The study, conducted by Nathan Kaib from the American Institute of Planetary Science and Sean Raymond from the University of Bordeaux in France, simulated and analyzed the continuous gravitational disturbances caused by passing stars on the solar system. The research indicates that Mercury’s orbit is already unstable due to the influence of Jupiter’s gravity, and the additional gravitational perturbation from a passing star could potentially cause collisions with the sun or Venus, triggering a chain reaction leading to Venus or Mars colliding with Earth.
In the most extreme scenario, Earth could be pushed by strong gravity towards Jupiter and eventually be kicked out of the solar system by Jupiter, resulting in the loss of sunlight and warmth, leading to the freezing extinction of surface life in the cosmic void. Although the probability of such a catastrophe is only 0.2%, it is significantly higher than previously estimated because earlier studies commonly overlooked the continuous dynamic impact of passing stars on the solar system.
Researchers involved in the study point out that within the next 5 billion years, there is approximately a 5% probability of the solar system encountering a passing star at a closer distance (less than 100 times the distance between Earth and the sun). Especially for stars with slower velocities (less than 10 kilometers per second), the effects on the solar system could be more profound, thus increasing the relative risk.
In addition to Earth, the future prospects for Pluto are also concerning. Despite its stable 3:2 orbital resonance with Neptune, simulation results indicate that if this stability is disrupted by a passing star, Pluto could face gravitational disturbances from other gas giants, with a high probability of being expelled from the solar system reaching up to 5%, which is 25 times the risk factor for Earth.
According to a report by Scientific News Network, Renu Malhotra, a planetary scientist from the University of Arizona, stated, “We may still be underestimating the vulnerability of the planetary dynamical system.” While she was not directly involved in this study, she believes that past events involving passing stars have already had an impact on the solar system.