Researchers from the University of Western Ontario in London, Canada, have estimated that Alpha Centauri, the closest star system to our solar system, may be shedding comets and asteroids into our solar system. Alpha Centauri, located 4.3 light-years away from Earth, consists of three stars revolving around each other. The researchers believe that if Alpha Centauri has an Oort cloud of distant comets similar to the sun, there could be up to a million objects larger than a football field now in our solar system.
Most of these objects are estimated to be in the far reaches of the solar system, beyond the orbit of Pluto, mixing with the sun’s own Oort cloud of cometary bodies. While astronomers have only detected one interstellar asteroid and one interstellar comet in our solar system, neither of these objects came from Alpha Centauri. The researchers suggest that just as Jupiter’s gravity can catapult objects into interstellar trajectories, the stars of Alpha Centauri and their planets could do the same to some comets and asteroids that pass by them.
Gregg and Wiegert estimate that a small percentage of the ejected objects, about 0.03 percent, pass through our solar system, but none of the large bodies are close enough for telescopes to detect. However, they believe that small particles from Alpha Centauri likely reach Earth’s atmosphere and estimate that up to 10 meteors worldwide come from Alpha Centauri each year. These numbers are expected to increase as Alpha Centauri gets closer, with the closest approach predicted to occur 28,000 years from now when it will be 3.2 light-years from Earth.
Despite the potential increase in meteors from Alpha Centauri, the number is still significantly low compared to Earth’s annual total of 7 trillion meteors. Additionally, since Alpha Centauri is located far to the south, its meteors are only visible in the far southern sky, making them out of sight for most people on Earth. Astronomer Simon Portegies Zwart from Leiden Observatory in the Netherlands cautions that the actual number of interstellar objects coming from Alpha Centauri may vary due to uncertainties in the rate at which Alpha Centauri ejects material. Nevertheless, the research highlights the connection between our solar system and other objects in space, such as Alpha Centauri and other neighboring stars.
