By most standards, space is exceedingly empty, containing on average just one proton per four cubic meters of volume. In this cosmic ocean, so incomprehensibly desolate and vast, entire galaxies are akin to scattered spots of sea foam—not to mention the stars, planets and other lesser objects that fade to insignificance against the void. For random clumps of matter adrift in the deep to somehow find each other seems to border on the miraculous.

Yet find each other they do, and in surprising numbers. Stars and planets routinely hurl smaller objects into interstellar space as an inescapable consequence of orbital mechanics. And the recent discovery of ‘Oumuamua—a mysterious and first-of-its-kind interstellar object spied by chance when it passed close by our sun last year—confirms as much. Statistical extrapolations suggest that a quadrillion trillion similar objects may lurk as yet unseen in the dark spaces between the stars of the Milky Way, so many that there should always be one such far-flung passerby flying through the notional sphere bounded by Earth’s orbit around our star. With an estimated size of roughly half a kilometer, ‘Oumuamua in some respects represents the tip of the interstellar iceberg; just as grains of sand greatly outnumber large rocks on a beach, for every ‘Oumuamua-sized body wandering the galaxy there should be many, many more objects even smaller. Scientists already know of many microscopic interstellar immigrants—cosmic rays and micron-sized flecks of stardust that occasionally strike spacecraft—but other than ‘Oumuamua, nothing larger has ever definitively been found.

Now two researchers—Avi Loeb, chair of astronomy at Harvard University, and Harvard undergraduate Amir Siraj—say that has changed, arguing that a modest meteor observed in January 2014 was actually an outcast from another star. They detail their result in a preprint submitted for peer-reviewed publication in the Astrophysical Journal Letters. If confirmed, the finding could help open a new frontier in the detection and study of interstellar meteors.