How do you make a cloud? On her show, Head Rush, Mythbuster’s Kari Byron demonstrates how clouds are formed by making one in a bottle.
For this experiment, you can use a bicycle pump with a rubber stopper attachment, rubbing alcohol and a clear 1 liter bottle. Don’t forget goggles and some adult supervision! Steve Spangler’s Science has more:
The reason the rubbing alcohol forms a more visible cloud is because alcohol evaporates more quickly than water. Alcohol molecules have weaker bonds than water molecules, so they let go of each other more easily. Since there are more evaporated alcohol molecules in the bottle, there are also more molecules able to condense. This is why you can see the alcohol cloud more clearly than the water cloud.
Clouds on Earth form when warm air rises and its pressure is reduced. The air expands and cools, and clouds form as the temperature drops below the dew point. Invisible particles in the air in the form of pollution, smoke, dust or even tiny particles of dirt help form a nucleus on which the water molecules can attach.
From the archives: clouds and experiments.
Update: Here’s an even more simple version of the experiment! Thanks, @nicolasdickner.
Sesame Street explains the hurricane to kids in an episode originally created for Hurricane Katrina and set to air again this weekend in the aftermath of Sandy.
Sesame Street - Hurricane Part 1, via explore-blog. To watch the rest of the episode visit, SesameStreet.org.
If you or your kids would like to help people who are still feeling the effects of Hurricane Sandy (or for any reason), there are many things you can do:
Hold a bake sale, wash cars and bikes, offer to rake the neighbors’ leaves, make holiday cards and sell them, or collect sponsors to pledge money for a walk/run/bike/skate/bowl/sled/etc-a-thon. Any of these activities are great ways to raise money for The Red Cross, Habitat for Humanity, the Humane Society, City Harvest, or Citymeals-on-Wheels, an organization that prepares and delivers meals to elderly New Yorkers. Donors Choose also has a special page to help teachers and classrooms effected by the hurricane: donorschoose.org/hurricane-sandy.
If you’re in the New York City/New Jersey area and would like to volunteer, visit NYCService.org, or search Volunteer Match for opportunities to help a wide variety of causes all across the country.
Featuring the incredible power of nature, this intense clip from Oceans, a French documentary film by Jacques Perrin (released in the US by Disneynature), shows dramatic footage of several kinds of ships (and a lighthouse) handling some seriously rough seas.
The Old Mill, a Walt Disney Silly Symphonies cartoon from 1937.
Like many of the later Silly Symphonies, The Old Mill was a testing-ground for advanced animation techniques. Marking the first use of Disney’s multiplane camera, the film also incorporates realistic depictions of animal behavior, complex lighting and color effects, depictions of rain, wind, lightning, ripples, splashes and reflections, three-dimensional rotation of detailed objects, and the use of timing to produce specific dramatic and emotional effects. All of the lessons learned from making The Old Mill would subsequently be incorporated into Disney’s feature-length animated films, especially 1937’s Snow White and the Seven Dwarfs.