175: Three lunar water mysteries with Prof. Ehlmann

Prof. Bethany Ehlmann returns to the show to talk about the mission she's leading, Lunar Trailblazer. This low-cost mission will hitch a ride to the moon using the extra space in a large rocket. Once there, it will help scientists learn more about water on the moon.

Follow Lunar Trailblazer on Twitter, and check out Trailblazer of the Week!