Jonathan Sneed is an astrogeologist and expert in Mars wind and erosional science. He also consults with science fiction authors, and has the skill of giving the sort of answers to science questions that are useful when writing fiction.

Numerous topics covered include - open questions in Mars science; panspermia; wind tunnels; and how entertainment technology is often ahead of technology made for any other industry. Also weird ideas for novels such as: an alien animal species that incorporates knowledge from brains through digestion; why a savannah planet can't work and how to make it work anyway; and a ninja in Florence! All this and much more.

As mentioned in the episode, he has a guest post on Ex Urbe, "What Color Is Pluto?"