planet nine

Say There Were A Black Hole In Our Solar System: How Would We Find It?

Say There Were A Black Hole In Our Solar System: How Would We Find It?

Last year, scientists published a paper with an iconic diagram: a black circle representing, to scale, a 5-solar-mass black hole—and the size of the hypothetical Planet Nine if it were a black hole instead of a planet. So, if Planet Nine really is a black hole, how would we find…