Interstellar Meteorites—“Supernova Bullets”?

Two meteors detected by a U.S. Defense Department missile warning satellite have trajectories that indicate they were not gravitationally bound to the Sun and hence arrived from other star systems. Both of these meteors appear to have anomalous material strength: one much stronger than typical iron meteorites. Given the rarity of iron meteorites of solar system origin (less than 5%), this is evidence that the population, and possibly origin, of interstellar objects is different than solar system meteors. Could the galaxy be full of iron or other heavy metal “bullets” ejected from supernova explosions?

An expedition to recover fragments from the first interstellar meteorite which fell off the coast of Papua New Guinea in 2014 has now been fully funded and may get underway within the next year.