When you teach a subject like physics you dig into the laws that make the physical world behave the way it does.  This question will come up when you start talking about gravity, space, universe and so on.  I've been asked this question a hundred times and I've found a way to answer this question in a non offensive way.  Thanks for listening everyone.  One more episode left in 2020.  I also got the sound right on this episode and I think it's my best recording.