Scientists Devise New Plan to Test If Mysterious ‘Planet Nine’ is Primordial Black Hole Ben Warren Posted on July 10, 2020 Posted in Aggregated No Comments Researchers believe enigmatic body could be a grapefruit-sized black hole with a mass of five to 10 times that of the Earth Share this:Share Share on Facebook (Opens in new window) Facebook Share on Reddit (Opens in new window) Reddit Share on X (Opens in new window) X Share on LinkedIn (Opens in new window) LinkedIn Email a link to a friend (Opens in new window) Email