Science Hobbies Rocket

Imagine sweeping the dust from a giant rock formation to uncover an ancient dinosaur fossil, or peering through your backyard telescope to identify a hazy comet as it streaks across the sky. Sound exciting? Believe it or not, several scientific discoveries were first observed by amateur hobbyists. While most hobbies don’t lead to important breakthroughs, they can be a fun way to learn about science. January is National Hobby Month, so this is the perfect time of year to explore some new activities. The investigation below will introduce you to the hobby of rocketry. If building rockets isn’t your thing, you might try some other science hobbies, like collecting rocks, observing weather or flying kites. Who knows, your hobby might even turn into a career one day.

Caution: This activity requires adult supervision.

Materials:
35 mm film canister
effervescent tablets
(such as Alka-Seltzer)
water
construction paper
tape
scissors
(The canister should have a lid that snaps inside the rim. Most white or transparent canisters have this type of lid. The black canisters with the gray lids that snap over the rim will not work.)

To Do:
1.) Find an area outside that is not too crowded and a safe distance from any buildings or trees. A solid surface, such as concrete, works best. (If you plan to launch your rocket in the grass or dirt, put a piece of wood or other hard material on the ground.)
2.) Place the film canister on the ground and fill it approximately 1/3 to 1/2 full of water.
3.) Carefully break your effervescent tablet in half. Set one of the pieces aside for later.
4.) Drop the remaining piece of tablet into the canister and quickly put on the lid.
5.) Turn the canister over so the lid is touching the ground and then stand back!
6.) Watch your rocket shoot into the air.
7.) If your rocket doesn’t fly as high as you would like, launch it again. It takes some practice to get the right technique and the proper amount of the ingredients.


Now Try This:
Can you make your rocket fly higher by altering the shape of the rocket or the ingredients that you add to the film canister? For example, you might fashion a nosecone or fins out of paper and attach them to the canister (see photo above). Or try adding a larger piece of effervescent tablet or a different amount of water. You can even substitute vinegar and baking soda for the water and Alka-Seltzer. Keep investigating until you find the perfect combination.

What’s Going On?
The main ingredients in the effervescent tablet are sodium bicarbonate and citric acid. When the tablet dissolves in the water, these chemicals react to produce carbon dioxide gas. This gas builds up inside the canister until the pressure becomes so great that the lid pops off and the gas rushes out. The escaping carbon dioxide gas pushes against the ground, causing the canister to shoot into the air. This film canister rocket is an excellent demonstration of Newton’s third law of motion, which states, “Every action has an equal and opposite reaction.” The same scientific principle applies to real rockets, except a chemical propellant replaces the effervescent tablet.

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Debbie DeRoma is the education manager at the Reuben H. Fleet museum.

Super Science Projects

Supplement your child's education with these do-it-yourself
Super Science Projects

Klutz Guide to the Galaxy
$19.99; 8+ years
klutz.com

Explore the universe from your backyard with a build-it-yourself telescope, night-sight flashlight, sundial, star and moon maps and an astrolabe. Includes loads of space-science activities.
“Very exciting and fun,” says Evan, age 11.

Reptile Hunter Super Throw Net
$14.99; 5+ years
BackyardSafari.com

Budding herpetologists can explore reptile wildlife by catching and observing lizards, turtles, frogs and salamanders.
“Keeps your child active and busy outside. Field guide requires parent’s assistance.”

Science on a Fossil Dig
$19.99; 5+ years
Kidsciencekits.com

Use the included brush and scraping tools to dig for real fossils! A magnifying glass and fun fact cards help kids learn about their finds: brachiopod, gastropod and “squid” shells and a fossilized shark tooth.
“Looking for fossils and trying to guess what it will be is a fun treat,” says mom Tianna.

Growums: Ratatouille Garden
$9.95; 5–12
Growums.com

Gardening combines with virtual world fun. Kits include seeds, magical coco or peat pellets and everything needed to grow vegetables or herbs for a salad, pizza, herb, taco, stir fry or ratatouille. Kids can register their garden online and watch animated mini videos to learn how to care for their seedlings. Weekly emails discuss watering, weeding, growth cycles and more.
“Easy,” says mom Francine. “All you need is a pie tin.”    
“Wow, I can grow my own vegetables!” says Evan, age 11.

MIracle Gro Mini Greenhouse or Terrarium
$12.99; 5+ years
PeachtreePlaythings.com

Grow your own flower, vegetable and herb gardens. Kid-safe kits feature the Miracle-Gro Gro-Pod system and Gro-Mix!
“This is so cool!” says Matt, 11.
Naomi, 9, says, “This is the perfect thing for me because I like planting stuff.”

Magic School Bus: Blast Off Erupting Volcanoes
$19.99; 5+ years
kidsciencekits.com

Study the science of volcanoes! Paint the volcano, mix up some “lava” and watch it explode. Learn about the layers of the Earth, study tectonic plate movement, explore different volcanic shapes and eruptions and make real pumice float. Includes a poster with volcanic facts, pictures and stickers.
Parental help required with this fun but somewhat messy project.

Magic Pepper

Abracadabra! Did you know that June 12 is National Magic Day? Why not celebrate by putting together a magic show full of science trickery. After all, many magic tricks and illusions are based on scientific phenomena. Here is a simple science trick to get you started.

Materials:
pie pan (or other shallow dish)
water
liquid soap
black pepper

To Do:
1.) Fill the pan approximately half full with water.
2.) Place the pan on a flat surface.
3.) Evenly sprinkle a layer of pepper across the surface of the water.
4.) Carefully dip your finger into the pepper and water. What happens?
5.) Now, place a drop of soap on a different finger and dip the finger into the pepper and water. What do you notice?


Now Try This:
Try the trick again but substitute flour or baby powder for the pepper. Do you get the same result? What happens if you use a soap-covered toothpick in place of your finger?

When you perform this activity as a magic trick, you should put the dish soap on your finger ahead of time. Ask a friend or family member to place his finger in the pan of pepper and water. When nothing happens, explain that the pepper only responds to people who have a magic touch. After saying a few magic words, place your soap-covered finger into the pan. Your audience will be amazed when the pepper rushes to the edges of the dish. They will be even more impressed when you explain the science behind the trick.

What’s Going On?
Although the pepper appears to run away from your finger, it is actually the water that is moving. The secret behind this trick has to do with something called surface tension. Water molecules have a very strong attraction to one another and they prefer to stick together. Their strong attraction creates a thin “skin” on the surface of the water. As long as this skin remains undisturbed, the pepper floats on top of the water’s surface.

When you place your soapy finger in the pie pan, the soap decreases the surface tension in the surrounding area by breaking up the attraction between the water molecules. This causes the water to pull away from your finger, taking the pepper along for the ride.
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Debbie DeRoma is the education manager at the Reuben H. Fleet Science Center.