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160: Going back in time with Dr. Bottke
Spacepod
English - September 22, 2019 16:00 - 20 minutes - 23.8 MB - ★★★★★ - 377 ratingsAstronomy Science Earth Sciences earth saturn spaceexploration stars asteroids astronomy galaxies jupiter mars mercury Homepage Download Apple Podcasts Google Podcasts Overcast Castro Pocket Casts RSS feed
Previous Episode: 159: Constellations and coordinates with Dr. Rich
Next Episode: 161: Dusty mysteries with Prof. Hartzell
Dr. Bill Bottke stops by the show to talk about ancient craters on the Moon and Earth. He tells us about how you can figure out crater ages by looking at the nearby rocks, and how that led him and his colleagues to figure out that the impact rate on Earth changes with time.