Full podcast episodes: Support: Follow: and What is the “missing baryon problem”? How do we know how many baryons there ought to be? What does the cosmic web have to do with it? What the heck is a baryon, anyway? I discuss these questions and more in today’s Ask a Spaceman! Follow all the show updates at , and help support the show at ! Keep those questions about space, science, astronomy, astrophysics, and cosmology coming to #AskASpaceman for COMPLETE KNOWLEDGE OF TIME AND SPACE! Music by Jason Grady and Nick Bain.