earth and planet X are expanding in the same direction (if directions existed - talking relative to the center of the universe)
But then again - what about black holes? Their gravity is so strong that it swallows light, right? So does this mean that light is affected (no matter how little) by gravity?
"And Shepherds we shall be, for Thee my Lord, for Thee. Power hath descended forth from Thy hand that our feet may swiftly carry out Thy command. We shall flow a river forth unto Thee And teeming with souls shall it ever be. In nomine Patris, et Fili, et Spiritu Sancti."