Can meteorites come from other star systems?
Not as far as anyone has confirmed. Three interstellar objects have been seen passing through the Solar System, including 'Oumuamua in 2017, but no meteorite has been proven to come from another star system, and claims of an interstellar meteor remain disputed.
Interstellar visitors do exist. In October 2017 the Pan-STARRS telescope in Hawaii discovered 'Oumuamua, the first object confirmed to be passing through the Solar System from interstellar space. Its speed and hyperbolic path, an orbit not bound to the Sun, proved it came from elsewhere. It was small, reddish and apparently elongated, and it accelerated slightly in a way not fully explained; most scientists favour natural explanations, such as gas escaping from ice. In 2019 a second visitor, 2I/Borisov, was found and was clearly a comet. A third, the comet 3I/ATLAS, was discovered in July 2025.
If such objects pass through, some interstellar dust and pebbles must occasionally strike Earth. Proving it is very hard, because the key evidence is a speed too great for anything bound to the Sun, and measured speeds have uncertainties. One widely publicised case concerns a fireball over the Pacific Ocean near Papua New Guinea in January 2014, recorded by US government sensors. Some researchers argued that its speed made it interstellar, and in 2023 an expedition recovered tiny metallic spherules from the seabed claimed to come from it. Many other scientists dispute both the speed estimate and the link to the spherules, some of which may be ordinary industrial or volcanic material or natural micrometeorites. The claim remains unconfirmed.
Laboratories do hold genuine material from other stars: presolar grains, specks of stardust older than the Sun found inside primitive meteorites. These grains formed around other stars before the Solar System existed and were incorporated as it formed, so they are not interstellar meteorites in the usual sense.
So, for now, every recognised meteorite comes from our own Solar System, mostly from asteroids, with a few hundred each from the Moon and Mars. Future surveys may catch an interstellar object with clearer evidence.