A primordial black hole of 1000 Earth masses is only 17 meters wide. It's effectively impossible to see, with a event horizon temperature of 0.02 millikelvin. I

A primordial black hole of 1000 Earth masses is only 17 meters wide. It's effectively impossible to see, with a event horizon temperature of 0.02 millikelvin. If it was extragalactic, it'd pass through our solar system at a pretty good clip. It could certainly do unfortunate things to Earth's orbit. A normal stellar mass black hole would be even worse. Very unlikely, of course. But not fictional.