Watch an astronaut play liquid ping pong in space
by David Pescovitz from on (#11T2T)
NASA astronaut Scott Kelly demonstrates ping pong with a sphere of water on the International Space Station. From NASA:
The paddles are polycarbonate laser etched so that the surfaces are actually arrays of 300 micrometer posts (0.3mm). The surfaces were then spray coated with a Teflon coat. The combined effects of surface roughness and non-wettability produce a super-hydrophobic surface capable of preventing water adhesion in dynamic processes. The larger the drop, the less force it takes to break it up. The smaller the drop, the harder you can hit it. Scott is demonstrating about a 4 mL drop (over 100 times larger than a rain drop).
