Scientists have identified more than 6,000 planets beyond our solar system, known as exoplanets, by observing how objects with planetary mass exert gravitational effects on their host stars. However, new research suggests that some of these objects may not be planets after all. Instead, they could be primordial black holes—tiny, extremely dense objects that may have formed shortly after the Big Bang, during the earliest moments of the universe.

According to the study, which was uploaded to the arXiv preprint server and has not yet been peer-reviewed, primordial black holes could behave in ways that closely resemble planets. Because they can have masses similar to planets and influence the motion of nearby stars, current detection methods may mistakenly classify them as exoplanets. If confirmed, this idea would challenge long-held assumptions about planetary discoveries and offer a new way to study the conditions of the early universe.