Moving liquids without gravity aboard the International Space Station can be tricky – if there’s no “down” then water won’t flow downhill. Capillary Flow Experiments-2, or CFE-2, a physical science investigation looking at fluid physics, is a set of experiments exploring how fluids move up surfaces in microgravity.
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Interview with Mark Weislogel, Principal Investigator, Capillary Flow Experiments-2
Mark Weislogel talks about the Capillary Flow Experiments-2, which is on the International Space Station.
Surface tension of water in microgravity
(Part 1 of 2) In this experiment Expedition Six NASA ISS Science Officer Don Pettit demonstrates the surface tension of water.
Surface tension of water in microgravity #2
(Part 2 of 2) In this experiment Expedition Six NASA ISS Science Officer Don Pettit demonstrates the surface tension of water.
Episode 1: Dancing Droplets
Challenge Question: In the end of the video, Dr. Pettit put a nylon knitting needle near the syringe used to squirt water droplets onto the Teflon knitting needle. Why did Dr. Pettit need a nylon needle near the injected drops and why must the other needle be Teflon?
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Episode 2 : Bistro-nauts
Challenge Question: Why can’t you use a regular cup in microgravity?
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Episode 3 : Thin Film Physics
Challenge Question: Why does the shape of the water sheet affect the direction of the Marangoni convection?
Episode 4: Lenses and Vortices
Challenge Question: How does the viscosity of the fluid influence a vortex?
Episode 5: Fun with Antibubbles
Challenge Question: When the water sphere rotates, why do the bubbles center themselves?
Episode 6: Earth in Infrared
Challenge Question: Why do plants appear red in infrared pictures and cities grey?
Episode 7: Space Soundwaves
Challenge Question: Why does Don use low frequencies to get the water to jiggle?
Episode 8: Goo!
Challenge Question: Don’s cornstarch solution is a shear-thickening non-newtonian fluid. What would change if Don used a shear-thinning fluid such as ketchup?
Episode 9: Electric Didgeridoo
Challenge Question: Why does the amount of water on the speakers affect how often droplets are ejected?
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