Everywhere we go, we find life that is compatible with us, that has the same basic genetic code.  Worlds we can live on are far more common and far more hospitable than pre-space scientists suggested.  Why?  Why are the Aliens we meet as human as we are?  Why do so many systems have so many habitable worlds?  Why is life out there related to life right here?  These are real big questions, and we are searching for the answers real hard.