Slow Motion Video Reveals How Raindrops Fall on Sand Like Asteroids

Physics





Photo credit:

R. Zhao et al., PNAS 2014

What does a rainy day on the beach and catastrophic asteroid strikes have in common? Despite the massive difference in scale, a whole lot it turns out, according to new work published in Proceedings of the National Academy of Sciences this week. Using high-speed imaging, researchers have captured the impact of raindrops falling on sandy surfaces: the surface deforms like a liquid while preserving a circular crater like a solid -- just like when an asteroid strikes Earth.