A black hole entering our solar system could absolutely change how planets move. Like any object with mass, black holes exert gravity—but their gravitational influence can be extreme depending on how massive and how close they are.
If a black hole were to pass near the outer edges of the solar system, it could disrupt the orbits of distant objects like comets in the Oort Cloud, sending them hurtling toward the inner solar system or flinging them into deep space. It could cause serious gravitational disturbances to the planets if it came even closer.
The degree of disruption would depend on two key factors: the mass of the black hole and its proximity to planets. For example, a black hole as small as one with asteroid-level mass passing as close as the Moon is to Earth could subtly alter the orbits of satellites, changing their altitude in measurable ways. A more massive black hole, passing nearer to a planet like Earth or Jupiter, could cause noticeable orbital wobbles or even force the planet into a new, more eccentric orbit around the Sun.
In extreme cases, if a black hole passed very close to a planet or Moon, its gravitational pull could potentially rip that object from its orbit, ejecting it from the solar system entirely or capturing it into orbit around the black hole itself.
Interestingly, if the Sun were to be replaced by a black hole of equal mass suddenly, the planets would continue orbiting as they do now because the gravitational force would remain unchanged. However, life on Earth would cease without the Sun’s light and heat, but the orbits themselves would be unaffected.
