How to spot tiny black holes that might pass through the solar system 

Primordial black hole flybys might tweak the orbits of planets and GPS satellites

An illustration shows a black hole, indicated by warped light, near a planet in the solar system

A primordial black hole in the solar system (illustrated) could make its presence known by altering the orbits of planets.

Benjamin V. Lehmann, with use of SpaceEngine@Cosmographic Software LLC

Black holes about the size of a hydrogen atom could be careening through the solar system unnoticed.