It's an Earth Thing

I think it's kind of neat how liquid moves sometimes. I have a nice hot chocolate going. The microwave is on one end of the kitchen so I need to turn around the opposite direction to leave the kitchen again. I do my 180 quickly but carefully so as not to spill the liquid, executing my turn around the mug rather than moving the mug around me, and watching it in case I spill. I move, the mug moves, but the hot chocolate stayed facing the same direction, at least the top half of it. Like when I turned, the mug moved around it without disturbing the contents. Cool stuff. Yup I just wasted a minute of your life.