How do black holes form? Why are there only two sizes (Small and Big Gulp)? How do we know black holes exist, and what purpose do they serve in the universe? I discuss these questions and more in today's Ask a Spaceman!

Keep those questions about space, science, astronomy, astrophysics, and cosmology coming to #AskASpaceman, Twitter@PaulMattSutter,, and for COMPLETE KNOWLEDGE OF TIME AND SPACE! Music by Jason Grady and Nick Bain.