Tootfinder

In a few days the #PlanetNine hypothesis - first published on 20 Jan 2016 in the paper https://iopscience.iop.org/article/10.3847/0004-6256/151/2/22 ("EVIDENCE FOR A DISTANT GIANT PLANET IN THE SOLAR SYSTEM", yes, they shouted it in all caps) - will turn 10 years old. The proposed big outer solar system inhabitant has never been found: https://www.skyatnightmagazine.com/space-science/planet-9-x-y-edge-of-solar-system reviews the situation.