I was putting together ideas for a new scifi story and one element kind of threw me...how would open water, like say in a swimming pool, act on the Moon? I read up a lot on different science subjects, but I'm no expert on fluid dynamics or low gravity physics. So I posed the question to Reddit's Scifi Board, and got a lot of great responses.
Some interesting conclusions from the responses, summarized here:
-- Without so much gravity pulling on the water, intermolecular attraction plays a bigger role in how the water behaves. For example, surface tension would create a meniscus (basically a broad hump of water) in the middle of the pool. It may be possible to over fill the pool by an inch or so, as the meniscus would 'suck' the excess water into the middle of the pool.
-- When you got out of the water, much more water would cling to you. As one commenter pointed out, it could be a liter worth of the stuff. So just toweling off might not be enough if you bathed or went for a swim--you may need to scrape off the excess water first.
-- Waves would propagate much higher than Earth. You cannonball into a lunar swimming pool, instead of foot-tall waves, you'd create a mini tsunami with maybe 5-6 foot waves. Splash fights could become truly epic. It seems to me that the sides of swimming pools would actually have to be high, sloping, and segmented it order to break up possible high rogue waves and prevent a lot of spillover.
-- The waves and water motion would move slower than they would on Earth, though, seeming to go in slow motion. Just as astronauts hopping on the moon seem to move slowly because they 'float' downward, it would be the same with the water motion because of the lesser gravity.
-- Stunt swimming and diving could also become truly epic,as you'd be able to swim and jump and dive in the water like a dolphin.
Just some interesting stuff to contemplate. Maybe someday our children or grandchildren or great grandchildren will actually see some of this for real, when they vacation on colonies on the Moon...