Guest: Gus Frederick was our guest for this Space Show program in order to discuss Martian caves and lava tubes with us. You can follow along in the discussion with these two websites and the instructions provided by Gus: 1) The Caves of Mars located at http://www.highmars.org. 2) Caves of Mars Illustrations located at http://www.highmars.org/marscave. Gus provided other URLs during the show and you will want to see the pictures and graphics he discusses. We talked not only about Martian caves and geology, but their analogs here on Earth and possible similar features on the Moon. Listeners had many questions for him. One question dealt with the lower Martian gravity and the fact that the lava flow is about three times the size of what it would be on Earth. Other questions inquired about orbital information and you will want to hear what Gus says about the possible use of robots on Mars for cave exploration. Gus provided some very good and informative information about various caves on Earth and specifically in his area, Central Oregon. We also talked about educational outreach using these subjects from school age to adults at Rotary Club meetings. Our discussion covers Martian geology and caves and we certainly look forward to hearing more from Gus and advancements and new information becomes available. If you have questions and comments for Gus Frederick, please send them to me at drspace@thespaceshow.com.