Knows in example sentence
All right, I'll grant you that some of the science in "Doppelganger" (or "Journey To The Far Side Of The Sun") is kind of dopey.The idea of an entire planet existing undetected (because we can't see it on the other side of our sun) doesn't hold up at all - any Astronomy 101 student knows that another planet the size of Earth would cause gravitational perturbances in the motions of other planets.