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Did Dinosaurs Swim?

Did dinosaurs swim? In 2014, one paleontologist’s dino-mite discovery led to a conversation about where dinosaurs spent their days. Did they all roam Earth or did they swim? We turned to National Geographic's “Mister Big” to introduce you to a dinosaur like you’ve never seen before.

Imagine: It’s the middle of the Cretaceous period, about 100 to 94 million years ago. You’re standing in what is today’s southeastern Morocco. Dinosaurs, including at least three great predators roam Earth’s lands. Six or seven types of crocodiles and 8- to 25-foot fish swim through the rivers. Large reptiles fly through the sky. 

How can all of these predators coexist? 

In a quest to answer that question, paleontologist Nizar Ibrahim made an even bigger discovery– the first known dinosaur that spent a substantial amount of time in water. 

Meet Spinosaurus aegyptiacus

This is a dinosaur that stretches 50 feet long from nose to tail with a six- to seven-foot smooth sail on its back. Beneath the dorsal fin is a dense, barrel-shaped torso. Its enormous skull is held up by its long neck. A long slender snout resembles that of a crocodile, and its short hind limbs are disproportionate to its dense and powerful forelimbs.  

Spinosaurus is incredibly front heavy,”  paleontologist Paul Sereno tells National Geographic. Serena, Ibrahim’s postdoctoral adviser at the University of Chicago, also discovered several notable North African dinosaurs, including Suchomimus, a relative of Spinosaurus with long, crocodile-like jaws. “It’s like a cross between an alligator and a sloth.”

The animal was originally discovered and named by Ernst Freiherr Stromer von Reichenbach between 1910 and 1914. Fossils of Stromer’s Spinosaurus were displayed in Munich’s Bavarian State Collection for Paleontology and Geology. But, in April 1944, a World War II Allied air raid destroyed the museum. Unfortunately, all that was left of the Spinosaurus was Stromer’s field notes, in which, according to National Geographic, he had concluded that the animal was “highly specialized.” But specialized for what was a question that remained unanswered.  

It was previously thought that while most dinosaurs might have had the ability to swim at some capacity, they were predominantly land animals. No one imagined dinosaurs swimming alongside crocodile and large fish—until March 2013.

After a long journey and hard search, Ibrahim was brought to a place in Morocco whose surrounding cliffs proved huge rivers had flowed 100 million years ago. And there they were– the Spinosaurus fossils Ibrahim had been searching for. 

According to National Geographic, after piecing together the bones with CT scans and digital reconstruction software, the paleontologists “wrapped the skeleton in digital skin to create a dynamic model of the animal’s center of gravity and how it moved. Their analysis lead to a remarkable conclusion: Unlike all other predatory dinosaurs, which walked on their hind legs, Spinosaurus may have been a functional quadruped, also enlisting its heavily clawed forelimbs to walk.”

This finding encouraged Ibrahim and his team to view the Spinosaurus as an animal spending its days in water rather than on land. With that perspective, the rediscovered dinosaur began to make more sense. 

National Geographic explains that the placement of the nostrils would have allowed the animal to breathe while its head was submerged. The barrel-shaped torso was similar to that of dolphins and whales. While the disproportionate hind legs wouldn’t be ideal for walking, they would have been perfect for paddling. It’s long, croc-like jaws and teeth would have been a great tool snacking on a large fish. 

While it is still believed that many dinosaurs spent time in nearby rivers and lakes, Ibrahim believes the Spinosaurus would have spent about 80 percent of its time immersed in water. This belief makes the Spinosaurus the first of its kind. That is until the next dino-mite discovery!

Photo credit: National Geographic 

From Deep Sea to Outer Space: Experts Weigh in on Pressurized Suits

This blog post is courtesy of Kit Matthew, The Children's Museum's Chief Science Educator. Kit helps infuse science throughout the museum by working alongside the exhibit and education departments, and by seeking out researchers and engineers who have interesting science stories and discoveries for us to share with visiting families.

Our bodies are finely tuned to life on Earth. You don’t even have to think about the fact that at any given moment every square inch of you is being pressed on by 14.7 pounds of atmospheric pressure–talk about having a lot of weight on your shoulders! Fortunately there is air inside our bodies balancing out that pressure, allowing us to survive on earth.

When we travel to extreme environments to explore unknown conditions—like outer space or deep in the ocean—our bodies have to contend with the changes in external pressure. Engineering is needed to create solutions to help balance the pressure and keep our bodies safe. Introducing… life support suits! (Think Tony Stark, according to a recent New York Times article.) 

We called on our museum experts who have traveled to space—Extraordinary-Scientist-in-Residence/Former Astronaut, Dr. David Wolf—and deep in the ocean—Extraordinary Underwater Archaeologist in Residence, Dr. Charles Beeker—to weigh in on this new incredible technology and how it plays a pivotal role in essential research work that needs to take place in these extreme environments. 

Dr. David Wolf and Dr. Charles Beeker


Exploration of outer space reached an extraordinary milestone with the Apollo 11 lunar mission in 1969 when Neil Armstrong walked on the moon. How was that even possible in the thin atmosphere of outer space?  What did that space suit really do for Armstrong to protect him and yet allow him to walk?

Now instead of journeying outwards away from earth, think about journeying deep under water. A similar problem needs to be solved—protecting the diver while allowing them movement to explore and do work. With the development of the advanced diving suit, much like Armstrong’s suit for outer space exploration, this becomes possible—a huge breakthrough!  

These new atmospheric pressurized diving suits are being initially tested at depths limited to 1,000 feet, but in the future they could allow divers to go much deeper and work up to 2.5 days without surfacing!  

There are a lot of moving parts that are required to protect from the extremes—both in space and in the ocean. We need:
•    Oxygen delivered to our lungs at just the right pressure to fuel our tissues—too much or too little would have catastrophic consequences on your body and blood chemistry. 
•    Control over our body temperature from extremes of hot and cold—temperature can vary over 500 degrees in a matter of minutes. 
•    A very tough, tear resistant suit for working with heavy and sharp equipment. 
•    Reliable communications with our other team members 
•    Dexterity to move around and handle tools without quickly exhausting the diver or astronaut. 

These are complex requirements to solve all at once. New products, like these suits, are cyclic—initial design, test models or prototypes, re-design, build the real thing, and adjust based on feedback from users under real conditions. Each iteration allows us to explore further and be more productive.

For example, this picture is a prototype spacesuit, called the AX-5, that NASA tested in the 1980's.  For space it keeps the internal pressure above the much lower ambient pressure of space. It wasn't used in space, but it showed us how to build better suits like those now used on the International Space Station.  

Oceans and space are oddly similar next frontiers!  This new, exciting engineering helps us advance our knowledge in both extreme environments.

Conserving Captain Kidd's Cannon

CannonBy Ashley Ramsey Hannum, Archaeology Lab Assistant

Have you been wondering if we would ever finish treatment on Captain Kidd’s cannon? You certainly wouldn’t be alone. Cannon #4 from Kidd’s Quedagh Merchant, which sank off the coast of the Domincan Republic in 1699, has been undergoing conservation treatment in the National Geographic Treasures of the Earth exhibit since 2011. The lengthy treatment, called electrolytic reduction, helps remove all of the salts that the cannon absorbed from 300 years in ocean water. The process also helps remove the thick layer of minerals and concretion that built up over that time. 

After years of conservation, the cannon is finally ready for the last stages of treatment. The first—and most challenging—step is boiling the cannon in highly purified water. The boiling water creates tiny bubbles inside the pores of the iron, helping to remove the final amounts of salt and minerals. 

You may be thinking, how does one boil a 1,500 pound, over 6 foot long piece of iron? Since we certainly don’t have a stove that big, we had to get creative. The Museum’s awesome facilities team had the idea to divert steam from one of the building’s giant boilers, typically used to heat the museum, through the water in the cannon’s tank. Theoretically, the heat from the steam should bring the water to a boil. 

We placed the cannon in an 8 foot long, galvanized steel water trough, designed for holding water for livestock. Steve, our HVAC extraordinaire, created some custom copper pipes, which brought steam from the boiler through the water. The steam took quite a long time to heat the water. Imagine how long it takes to boil about a gallon of water to make spaghetti. Well, we needed to boil 220 gallons of water to cover the cannon. It took almost 7 hours to bring it to a boil! 

After a couple weeks of intermittent boiling, all of the last salts were successfully extracted. The cannon is now soaking in an alcohol bath to dehydrate it without exposure to air. Once all of the water has been removed, it will be ready for its final coating and sealants. The cannon can then be safely stored in air without risk of rapid deterioration. 

New shipwrecked artifacts are now installed in the exhibit, and the process begins all over again!
 

Treasures of the Earth gallery manager, Josh Estes, visits Captain Kidd's cannon.
Cannon then

Conservator Christy O'Grady shares the cannon with visitors in the Wet Lab.
Cannon

Christy and Ashley carry out final steps in the cannon's conservation treatment.

Cannon Cannon

Saturday Science: Handmade Microscope

Saturday Science: Handmade Microscope In a past Saturday Science, we learned how to use a drop of water as a magnifying glass. Today we’re going to kick that up a few notches and use a drop of water and a laser pointer to make a working laser microscope. You’ll be able to see single-celled organisms moving around inside the laser beam!

Materials

  • Pond water 
  • A laser pointer (you can often find inexpensive ones for $3-$5 near the check-out at the store)
  • A paperclip or copper wire
  • A binder clip large enough to fit around the laser pointer
  • Scotch tape
  • A white surface

 

Process

  1. Straighten out the paperclip, then wrap most of it around the front part of the laser pointer, leaving about an inch sticking out in front of the hole where the beam comes out. If you’re using copper wire, give yourself 3-4 inches so you have plenty to wrap around the laser.
  2. Secure the paperclip/wire to the laser pointer with tape.
  3. Carefully bend that leftover inch of paperclip/wire into a small circle, a little bigger than the laser pointer’s lens hole. Make sure it is centered right in front of the hole so the laser beam passes through it. This will hold your water drop.
  4. Clip the binder clip around the laser pointer closer to the front. Keep the two “arms” on the clip where they need to be to open/close it because they are the stand you will use to make sure your microscope holds steady.
  5. Dip your loop of paperclip/wire into your pond water. Carefully remove it, making sure there is a crop of water suspended inside the loop. If you’re having trouble getting the water droplet to stay inside the loop, make sure the loop is complete all the way around and the paperclip/wire is touching itself, forming a full circle. If there is space between one end of the loop and the other the water will have a hard time forming a stable drop.
  6. Carefully set your laser pointer down, using the binder clip as a stand, and point it at your white surface. Turn off all the lights in the room.
  7. Press the button to shine the laser beam through the water drop. It will show up on your white surface much bigger than normal and you’ll be able to see things moving around inside it. Experiment with distance: move the laser pointer closer to or further from the white surface to see what it takes to get the best focus and the sharpest image.

 

Summary

What are those things moving around in your laser beam?

Well, some of it is just the movement of the water. But the small dots and blobs are microorganisms that live in the pond water, like paramecia and amoeba. These single-celled organisms swim around the water using tiny hair-like structures called cilia or flagella. There may even be some single-celled plant-like lifeforms called diatoms. Your laser microscope isn’t powerful enough to make out fine details in these microorganisms, but how cool is it that you can see them moving around in the beam of a laser?

This works because the water drop is similar in shape to the lens of a real microscope. A lens takes the light waves moving through it and bends them so they start traveling outward as they leave the water drop. The laser beam continues expanding until it hits the white surface. The microorganisms swimming around in the pond water get in the way of the light, which means they cast shadows inside the laser beam. Those shadows are what you see moving around in the light.

Want more Saturday Science? See all of our at-home activities on the blog or on Pinterest.

Saturday Science: Sky in a Glass

Saturday Science: Sky In A GlassIt’s an age-old question: Why is the sky blue? 

With this week’s Saturday Science experiment, from Sciences 360, you can do more than answer this question when your kiddos ask; you can show them, too! 

Materials

  • Water
  • Milk
  • Clear glass cup
  • Flashlight

 

Process

  1. Pour some water into the glass cup.
  2. Shine the flashlight through the sides of the glass. The water should be clear. 
  3. Keep the flashlight light shining through the glass and add drops of milk to the water one at a time. 
  4. Keep adding drops of milk until your mixture becomes blue. 

 

Summary
Why did the milk turn your water blue? For the same reason the sky is blue! 

Milk contains tiny molecules of protein and fat which are nearly the same size as atmospheric dust. As you added drops of milk to the water, the beam of light emitted by your flashlight hit these tiny molecules, absorbed the energy, and then re-emitted it in different directions.

The same thing happens in our atmosphere when sunlight encounters tiny bits of dust. According to Sciences 360, “These particles absorb energy from the incident light, vibrate, and then re-emit the light, scattering it in all directions.” While all colors are scattered, blue and violet are scattered the most. This phenomenon is known as Rayleigh scattering. 

Rayleigh scattering makes our milk mixture and our skies blue because it is the blue light that reaches our eyes, which are more sensitive to blue than violet.

Want more Saturday Science? See all of our at-home activities on the blog or on Pinterest.

Saturday Science: Pretty Pennies

Saturday Science: Pretty PenniesFind a penny, pick it up, and all day long, you’ll have good luck. 

But why is it that most of the pennies you find are covered in brown dirt and grime? Is there a way to make your lucky penny shine brightly? You bet! In this week’s Saturday Science, found on The Teachers Corner, discover how to clean pennies with just a little ketchup and a little elbow grease. 

Materials

  • Several old pennies 
  • Ketchup (or anything with vinegar: hot sauce, mustard, salad dressing, or just plain old vinegar)

 

Process:

  1. Squirt some ketchup onto a plate. 
  2. Place 3 to 4 pennies into the ketchup. 
  3. Add a little more ketchup so that all the pennies are covered. 
  4. Let them sit for a minute or two. 
  5. Now, get your hands messy! Rub each penny with your fingers, and then rinse it off in a sink. 

 

Summary:
What happened? The ketchup made your pennies look like new! 

Before they became bright and shiny, your pennies were covered in copper oxide. Similar to rust, which is formed by the combination of iron and oxygen, copper oxide is a brown matter formed by copper and oxygen. 

The Teachers Corner explains that “when you put the penny into the ketchup, the vinegar in the ketchup combines with the copper oxide to form a chemical called copper acetate. Copper acetate dissolves in water, so you wind up with a nice, bright penny.”

Now give your bright and shiny penny to a friend, and then your luck will never end!

Saturday Science: Water Magnifier

Saturday Science: Water Magnifier When something is so small you can barely see it, how do you find out what it is? Why, use a magnifying glass, of course! In this week’s Saturday Science experiment, found on education.com, discover the magic of magnifiers with just a drop of water. 

 

Materials

  • 2 by 3 inch piece of cardboard
  • One-inch square piece of thin, clear plastic
  • Pair of scissors
  • Tape
  • Water
  • Spoon 
  • Newspaper

 

Process

  1. Carefully cut a dime-sized hole in the middle of the cardboard.
  2. Set the clear piece of plastic over the hole and tape it down. Tape it around the edges, without covering the hole. 
  3. Fold each end of the cardboard down 1/4 inch.
  4. Dip the tip of the spoon in the water. Hold the spoon directly over the center of the hole, and let one drop of water fall onto the plastic.
  5. Set a piece of newspaper with print on the table.
  6. Carefully lift the magnifier and set it down on top of the paper.
  7. Look straight down through the top of the water drop.

 

Summary
When you looked through your magnifier did the printing on the paper appear to be magnified? 

YES! 

A magnifying glass works because its shape bends the light waves passing through it. As the light waves leave the other side of the lens, it bends them so that they start traveling outward. By the time the light waves hit your eye, they’re much more spread out, and the thing you’re looking at appears larger. 

The water droplet in this experiment is doing the same thing! As it sits on the clear plastic, it takes a shape similar to the lens in a magnifying glass, and it spreads out the light before it reaches your eye.

Saturday Science: Water-Walking Wire Critters

Saturday Science: Water-Walking Wire CrittersHave you ever been at the lake, pond or even an outdoor pool and watched a bug land on the surface of the water and scurry around without sinking? Did you wonder how that little insect was capable of walking on water? To answer that puzzling question, we found this week’s Saturday Science experiment at Science Friday. Let’s make some water-walking, wire critters! 

Materials

  • Large bowl 
  • Water
  • Roll of thin (about 30-gauge), plastic-coated wire 
  • Sharp scissors or wire cutters
  • Paper clips 

 

Process:

  1. Cut a 12-inch piece of plastic-coated wire. 
  2. Bend the wire into a flat shape. This is your critter! 
  3. Fill the large bowl with water. Let rest until the surface is still. 
  4. Gently place your critter horizontally on top of the water. (If it doesn’t stay on the surface the first time, try again.) 
  5. Take your critter out of the water and dry if off. 
  6. Gently place your critter vertically in the water. 
  7. Take your critter out of the water and dry it off. 
  8. Gently bend your critter so that it can hold a paper clip above the water. 
  9. Gently place it back in the water. 
  10. Add a paper clip. 
  11. Repeat until your critter sinks beneath the surface. 

 

Summary:
When you placed your critter horizontally on top of the water, did it float or sink? 

Thanks to surface tension, your water-walking wire critter floated! According to Science Friday, “surface tension is caused by the attraction, or cohesion, of individual molecules to one another in a liquid.” When you gently placed your critter on top of the water, its weight was evenly distributed over an area of water and didn’t break the cohesion between the molecules. That caused your critter to “float” or “walk” on the surface of the water, even when adding additional weight with paper clips. But when you placed your critter vertically in the water, did it float or sink? It sank! This is because a vertical critter takes up a much smaller surface area, so the weight cannot be evenly distributed. When you placed your critter vertically in the water, the cohesion between the molecules broke, and your critter sank straight to the bottom of the bowl. 

 

Saturday Science: Handmade Horn

Saturday Science: Handmade HornDuring this Month of Sound we’ve made a couple of instruments that have helped us experiment with sound. This week we’ll make one final instrument to round out your homemade orchestra. You have a flute and a kazoo and now it’s time to add in the brass section with a homemade horn!

 

Materials:

  • A disposable rubber glove 
  • A plastic drinking straw 
  • A plastic water bottle 
  • A pair of scissors 
  • A rubber band 
  • Masking tape or painter's tape

 

Process:

  1. Snip a tiny hole in one of the fingers on the glove. Cut a few inches off of the straw and insert your new piece of straw in the hole. Tape it in tightly!
  2. Cut off the bottom of the plastic bottle. Have an adult help you make it even so it doesn’t snag or cut your skin.
  3. Put the glove over the top of the plastic bottle and wrap the rubber band around it to hold it as tightly as possible. You don’t want any air to be able to leak out!
  4. Hold your new horn so that the straw is in your mouth and the water bottle faces straight up and then blow through the straw. You’ll hear a loud foghorn sound!

 

Summary:
How loud can you play your horn?

With the glove tightly attached to the nozzle of the bottle and bent upward toward your mouth, not all the air you blow into it gets out at the same time. Since the glove is made of a stretchy, or elastic, material, it stretches out, lets some air through, and then contracts, or gets smaller again, and then stretches out to let more air through. This cycle repeats as long as you are blowing into it, but it happens very quickly, which makes part of the glove vibrate, which creates sound waves that travel into the water bottle. The sound vibrates the bottle and the air inside it, which creates resonance, more than one sound wave vibrating at the same frequency and making each other louder, which is why the horn is so loud.

Unlike your other instruments, your horn can’t change pitch to create different notes. But if you want a horn with a lower note, just cut the top and bottom off a second plastic bottle so you have a hollow tube and tape it onto the bottom of your first tube. Since it’s larger, it will vibrate more slowly and resonate with a deeper sound. If you cut the first bottle extra short it will vibrate faster, creating a higher sound. How many different kinds of horns can you make?

Want more Saturday Science? See all of our at-home activities on the blog or on Pinterest

Saturday Science: Secret Sounds

Saturday Science: Secret SoundsWe already know that sound is made of sound waves, vibrations traveling through the air to your ears. But can these sound waves travel through something other than air to your ears? How about a solid object? Let’s find out!

 

Materials

  • A wire coat hanger
  • Some string, yarn, or twine
  • Scissors
  • Something to use as a drumstick (a fork, a spoon, a pencil, an actual drumstick, etc.)

 

Process:

  1. Cut two pieces of your string, yarn, or twine about 1-1½ feet long.
  2. Tie your pieces of string to the corners of the wire hanger.
  3. Wrap the other ends of the string around the very ends of your index fingers a few times. Make sure it’s not so tight that it hurts or cuts of the bloodflow to your fingertips!
  4. Have an adult tap the long bottom part of the hanger with your makeshift drumstick while you hold it up. What does it sound like?
  5. Now stick your index fingers in your ears and have the adult tap the hanger again.

 

Summary:

What did it sound like with your fingers in your ears?

 

The sound that you heard was something only you could hear! Anyone standing close to you would have heard the same sound you heard the first time the hanger got tapped. That sound was the hanger sending sound waves through the air to everyone’s ears. When you wrap your fingers with the string and stick them in your ears, though, the sound waves vibrate the string, which sends those vibrations into your fingers and then directly into your ears!  Sound actually travels through solid objects more easily than through air because the molecules, the tiny particles that make up everything, are closer together in a solid object.

 

Sound can travel through liquid, too. Try this out next time you take a bath: tap a fork on the side of the tub under the water. What does it sound like? Now stick your head under the water and tap the fork again? Is it different when you’re under the water, too?

 

As long as there are molecules to vibrate, sound can travel. This is why sound can’t travel through space: empty space has no matter in it, so no molecules to vibrate!

 

Want more Saturday Science? See all of our at-home activities on the blog or on Pinterest.

 

Saturday Science: The Sound Sandwich

Saturday Science: The Sound Sandwich Let’s make a sandwich! We’re not talking about a sandwich you can eat for lunch, but rather a sandwich that makes beautiful sound! In this Saturday Science experiment from Exploratorium, discover how small adjustments to vibrations can raise or lower the pitch of sound.  

 

Materials:

  • 2 jumbo craft sticks
  • 1 straw
  • 1 wide rubber band
  • 2 smaller, thin rubber bands
  • Scissors

 

Process:

  1. Wrap your wide rubber band lengthwise around one of your jumbo craft sticks.
  2. Use the scissors to cut two 1-inch pieces of straw.
  3. Put one of the small straw pieces underneath the wide rubber band, about a third of the way down from the end of the stick.
  4. Take the other craft stick and place it on top of the first one.
  5. On the same side where you placed the straw piece, wrap one of your thin rubber bands around the end of the sticks, about a half an inch from the edge. The rubber band should pinch the two craft sticks together.
  6. Put the other small piece of straw in between the two craft sticks, about a third of the way down from the end of the stick. Don’t put the straw underneath the wide rubber band this time.
  7. Now, wrap your other thin rubber band around this end of the craft sticks, about a half an inch from the end. There should be a small space between the two craft sticks created by the two pieces of straw.
  8. Put your lips against one of the long edges of the craft sticks, between the small straws, and blow through the sticks! Did you make a sound?
  9. Move the straws closer together. Does the sound change?

 

Summary:

When you blow into the Sound Sandwich, you make the large rubber bands vibrate, and that vibration produces the sound. Think back to the straw flute we made last week: different vibrations create different sounds. Long, massive objects vibrate slowly and produce a low-pitched sound, while shorter, less massive objects vibrate quickly and produce a high-pitched sound. When you moved the straws closer together, you shortened the part of the rubber bands that can vibrate, so the pitch is higher than the pitch of the original sound. If you watch closely when someone else is playing the sound sandwich, you can watch the rubber band vibrate!

 

Want more Saturday Science? See all of our at-home activities on the blog or on Pinterest.

 

 

Saturday Science: Straw Flute

Saturday Science: Straw FluteThis week’s Saturday Science experiment, courtesy of Deceptively Educational, is music to our ears! Discover how sound waves make music by creating a straw flute. What song will you play?

 

Materials:

  • nine straws

  • ruler

  • scissors

  • clear tape

 

Process:

  1. Set aside the first straw – no cutting required.

  2. Line the second straw up against the ruler. Measure and cut two centimeters off the bottom of the straw.

  3. Line the third straw up against the ruler. Measure and cut four centimeters off the bottom of the straw.

  4. Repeat this process for straws four through nine, cutting two additional centimeters off the bottom of each straw (6, 8, 10, etc.).

  5. Lay a long piece of clear tape sticky side up on your table or work station.

  6. Stick the longest straw to the tape.

  7. Stick the second longest straw to the tape right next to the first. The tops of the straws should be even with each other.

  8. Repeat this process, longest straw to shortest, until all of the straws are stuck to the tape.

  9. Wrap the remaining tape around the straws so that the straws are secure.

  10. Play your straw flute by blowing air over each straw!

 

Summary:

What sounds did your straw flute make? Which straws made a high-pitched sound? Which straws made a low-pitched sound?

 

Sound is a wave, a vibration traveling through the air to your ears. The way a sound wave sounds to your ear is known as its pitch. The wave that creates it is measured in frequency, or the number of sound waves that hit your ear in a certain amount of time. A high-pitched sound is made by a high-frequency wave and a low-pitched sound is made by a low-frequency wave.

 

If you vibrate solid objects they make the air around them vibrate, creating sound waves. This happens when you blow through the straws in your straw flute. The different lengths of each straw vibrate with different frequencies, creating different pitches of sound. These pitches create different notes that allow you to play a song.

 

If you want to really see this in action, pluck some strings on a guitar. You can watch them vibrate and see how the high, thin strings vibrate faster than the low, thick ones.

 

Did you know that different animals can make and hear different sounds than humans? Dogs and many other animals can hear pitches that are too high for our ears. Whales, when they sing their whale songs, sometimes create pitches that are way too low for human ears, but whales can hear them just fine for hundreds of miles across the ocean!

 

Want more Saturday Science? See all of our at-home activities on the blog or on Pinterest.

Saturday Science: Crayon Rocks

Saturday Science: Crayon RocksWhile spending time outdoors this summer, have you noticed different types of rocks? Chances are that answer is, “Yes!” There are three kinds of rocks: sedimentary, metamorphic and igneous. In this week’s Saturday Science experiment, courtesy of Momma Owl’s Lab, learn how to create colorful crayon rocks and discover how each type of rock forms.

 

Materials:

  • 4 different colored crayons (multiple of each color) 
  • Pencil sharpener
  • 4 containers
  • 3 6"x6" pieces of aluminum foil
  • Popsicle stick 
  • Mug
  • Boiling water (Have a parent help you with this!)

Process:

  1. Unwrap the crayons and sharpen them. 
  2. Place each color of crayon shavings in a separate container. 

Create sedimentary rocks:

  1. Lay one of the aluminum foil squares flat on the table or work station.
  2. Add a few shavings of each color to the foil one at a time so that the colors form layers. 
  3. Fold the foil tightly around the shavings. 
  4. Compress the foil and shavings with your hands (or feet). 
  5. Keep compressing. It takes awhile for the shavings to stick together. 
  6. Carefully unfold the foil and remove your sedimentary rock!

Create metamorphic rocks: 

  1. Lay another aluminum foil square flat on the table or work station. 
  2. Layer the crayon shavings by color in the center of the square.
  3. Fold up the foil around the shavings to create a boat. 
  4. Have an adult pour boiling water into mug.  
  5. Place the boat into the mug and let it float for 20 seconds. 
  6. Remove the boat and fold the foil in half so that the shavings are compressed. (Be careful! The foil might be hot.) 
  7. Let it cool and solidify. 
  8. Open the foil and remove your metamorphic rock!

Create an igneous rock:

  1. Lay another aluminum foil square flat on the table or work station. 
  2. Layer the crayon shavings by color in the center of the square.
  3. Fold up the foil around the shavings to create a boat. 
  4. Have an adult pour boiling water into mug.  
  5. Place the boat into the mug and let it float for 1-2 minutes. Shavings should be completely melted.  
  6. Take the popsicle stick and stir the shavings until they are all mixed together.
  7. Remove the boat. 
  8. Let the crayon cool and solidify.
  9. Take a look at your igneous rock!

 

Summary:

You just created sedimentary, metamorphic and igneous rocks! Can you tell the difference between each one?

 

Sedimentary rocks are formed from sediments, or tiny rock particles, that were layered and then compressed together. This is similar to when you compressed the crayon shavings together between the foil. Sedimentary rocks have distinct layers of sediment and often have visible rock particles in them. If you’re looking at rocks from Indiana, you’re looking at sedimentary rocks, like limestone, sandstone and shale.

 

Metamorphic rocks are formed when existing rocks are exposed to heat and/or pressure. You recreated this process by using heat (the boiling water) to melt your crayon shavings and then adding pressure (when you folded the foil in half). Distinct bands or blocks of crystals can be found in metamorphic rocks.

 

Igneous rocks are formed when magma, or molten rock, cools and solidifies. You made magma by completely melting your crayon shavings and as that magma cooled and solidified, it became an igneous rock.  

 

There might be three types of rock, but it is important to note that no rock is “set in stone.” Given the right conditions, each can be changed from one into another.

 
Want more Saturday Science? See all of our at-home activities on the blog or on Pinterest.

Saturday Science: Pretty Pigments

Saturday Science: Pretty PigmentsWhen you visit the museum to see Terra Cotta Warriors: The Emperor’s Painted Army, you’ll notice faded paint on some warriors. While few examples of what the warriors originally looked like remain, we know that at one time these warriors were painted in bold and vibrant colors.

 

When China’s first emperor ordered the creation of these warriors, the color of each paint was created by crushing minerals into powder and adding liquid. Now, you and your family can explore this color creation at home by creating your own chalk paint!

 

Materials:

  • Colorful sidewalk chalk

  • Small plastic bags

  • Hammer (or similar tool)

  • Small bowls or cups

  • Water

 

Process:

  1. Place colorful sidewalk chalk into small plastic bags. Use a different bag for each color.

  2. Using a hammer or similar tool, crush the chalk into a powder. Be careful! The plastic bags might tear open and leak powder.

  3. Transfer the powder into small bowls and cups. You can create new colors by mixing different colored powders together. Ask your children to guess what colors these combinations will make.

  4. Add small amounts of water at a time, mixing carefully, until your paint is the thickness you desire. It may take quite a bit of mixing to create a smooth paint.

  5. Now your paints are ready to use! Children can create works of art on the sidewalk or on paper and pretend that they are artists working on the First Emperor’s amazing army.

 

Summary:

What colors did you make? It may not seem like it at first, but there’s some science going on in your artistic endeavor.

Art supplies like chalk, paint, crayons and colored pencils get their colors from substances called pigments. Pigments are made up of molecules that absorb some light and reflect other light. If you’ve ever seen a rainbow, then you know that the white light from the sun is made up of every color that’s in that rainbow. When white light hits a pigment, that pigment absorbs every single color from the hidden rainbow except the color that it is. So a red pigment absorbs every color but red. Only the red part of the light bounces off and enters your eye.

When pigments get mixed, suddenly you have two types of molecules each bouncing back a different color. When those two colors hit your eye at the same time, they mix, too! Yellow and blue pigments mixed bounce back green, blue and red bounce back purple, and so on. Some pigments occur naturally in plants and certain animals, and some are human-made, or synthetic pigments. They all share one thing in common, though: they made our lives brighter by adding color!

Be sure to get your tickets to see the Terra Cotta Warriors, at The Children's Museum now through November 2. 

Want more Saturday Science? See all of our at-home activities on the blog or on Pinterest.

 

Top 10 NASA Milestones Since the Apollo 11 Moon Landing

In this infographic, The Children's Museum's Extraordinary Scientist-in-Residence, former astronaut Dr. David Wolf, shares the Top 10 NASA milestones that have taken place since Apollo 11's lunar landing.

Top 10 NASA Milestones

Sunday, July 20 is Moon Day at the museum! 
Join us to celebrate the 45th anniversary of the moon landing as you meet museum science experts and dive into fascinating space topics like gravity, moon craters, and more!

Saturday Science: Balloon Hovercraft

Saturday Science: Balloon HovercraftHovercrafts are pretty cool. They use air to hover a couple of feet up and can travel over land, snow, and even water. Since air is all around us, with a couple of things from around the house you can wrangle that air into a small but functioning hovercraft!

 

Materials:

  • An old CD or DVD (make sure it’s one nobody wants to use anymore)
  • A pop-top from a water bottle or soap bottle
  • Duct tape
  • A pushpin
  • A balloon
  • A hot glue gun

 

Process:

  1. Tear off two 2-inch square of duct tape. Use them to cover the hole in the CD from both sides so there’s no sticky stuff exposed.
  2. Using your pushpin, poke 6-8 holes through the tape around the edge of the CD hole. This will concentrate the air flowing through and help the CD hover.
  3. Using your hot glue gun, glue the pop-top cap over the hole. Make sure the seal is completely airtight by opening the cap once the glue is dry and blowing through it. Air should only be coming through the holes you poked in the tape. If it’s leaking out the edges of the cap, add a bit more glue.
  4. When the glue is all dry you’re ready to add your air! Blow up the balloon as big as you can get it but don’t tie it off. Make sure that the pop-top is closed and pull the neck of the balloon down over the top part of it.
  5. Your hovercraft is finished! Pop the cap open to get the air flowing and watch it float!

 

Summary:

So how come the CD hovers instead of blasting straight up?

The CD hovers because the air coming through those holes you poked gets spread out into a cushion underneath the CD, pushing it up off whatever surface you put it on. This is partially due to a scientific principle called Bernoulli’s Principle, after scientist Daniel Bernoulli. It says that fast moving air has low air pressure and slowly moving air has high pressure. When you concentrate the flow of air through those tiny pushpin holes you raise the pressure and lower the speed to help it form that cushion rather than simply blasting the CD across the room (like when you let go of an untied balloon).

Experiment with different bases for your hovercraft. How does a paper plate work? A Frisbee? An old record album? If you want to kick it up a notch you can go online and find blueprints for a full-sized hoverchair you can ride! Just make sure you have an adult handy to help you build it!

Want more Saturday Science? See all of our at-home activities on the blog or on Pinterest.

Saturday Science: Air Rockets

Saturday Science: Air RocketsWhen we think of rockets we often tend to think of giant metal rockets, blasting up into space on a column of jet fuel. A rocket doesn’t need to shoot fire to get going. Isaac Newton’s laws of motion let us use lots of things as rocket fuel, even air!

Materials:

For your rocket launcher you will need:

  • One 10-foot PVC pipe, 1/2-inch in diameter
  • One 1/2-inch 90-degree PVC elbow
  • Saw or PVC cutter
  • Lots of 2-liter bottles
  • Duct tape
  • Twine

To build your rockets you will need:

  • Scotch tape
  • Old magazines (the kind with a staple in a center crease)
  • Cereal boxes
  • Scissors

Process:

  1. Using your saw or PVC cutter, have an adult cut your 10 foot PVC pipe into the following lengths:
    1. One 5-foot piece
    2. One 2-foot piece
    3. One 1-foot piece
    4. Two six-inch pieces
  2. Use the 90-degree elbow to connect the 5-foot piece and the 2-foot piece forming an L-shape. Stick ‘em in there tightly. You can glue them together if you want but sometimes the launcher is easier to transport if you can take it apart.
  3. Using your twine, tie the two 6-inch pieces across the 5-foot piece. They should be perpendicular to the 5-foot piece and about 3 feet apart from each other to act as stabilizers. The 2-foot piece should be facing skywards. Tie the twine tightly and secure it in place with some duct tape.
  4. Your launcher is almost done! Stick the open end of the 5-foot piece into a 2-liter bottle. Push it about an inch or so into the opening in the bottle. It will fit snugly but secure it with some duct tape just in case.
  5.  Now it’s time to make a rocket! Open your old magazine to the very middle and have an adult remove the staples for you. Pull out a sheet or two of paper.
  6. Using your last piece of pipe, the 1-foot piece, roll the pages around the pipe. You can go long-ways or short-ways, whichever you like. Once the paper is rolled all the way up around the pipe use the scotch tape to tape it lengthwise, creating a paper cylinder. Don’t make it too tight on the pipe or it won’t fit onto the launcher!
  7. Take your rocket body off the pipe. Using your scissors, make four 1/2-inch cuts in one of the open ends in an X-shaped pattern. Fold the four flaps down on top of each other and tape them shut until the top of your rocket is airtight.
  8. Cut some fins, whatever shape you like, out of the cereal box and tape them to the bottom of your rocket. Remember: fins are important for a rocket to fly straight but too many fins will weigh it down and make it fly a shorter distance.
  9. Slide your rocket onto the end of the 2-foot piece. You’re ready to launch! Give a countdown and then stomp as hard as you can on the 2-liter bottle.

Summary:

How far did your rocket go? A well-built rocket with a really good stomp can fly close to 200 feet in the air!

Big space rockets use Newton’s third law of motion to get moving: for every action, there is an equal and opposite reaction. The rocket fuel pushes down (action), and the rocket gets pushed up (reaction). Your rocket is a bit different. Newton’s first law provides the mechanism to get it moving: an object at rest tends to stay at rest unless acted upon by an outside force. The air in the 2-liter is at rest until you, the outside force, stomp on the bottle and get it moving. The rocket is at rest until the air hits it, putting it into motion, and then it shoots up into the sky!

You can get 20-30 good stomps out of one 2-liter bottle by blowing into the launcher and puffing it back up with air over and over. Make sure you put your hand around the launcher so your lips don’t touch the pipe, though! When your bottle is about finished, just take it off and pop a new one on. Experiment with different sizes and shapes of rockets to see what flies the best!

Want more Saturday Science? See all of our at-home activities on the blog or on Pinterest.

How Fireworks Work

Fireworks are more than just a loud bang and beautiful colors showering the night's sky—they're chemistry in ACTION! This Fourth of July, learn and teach your kids how fireworks work.

Remember—safety first! It's always best to see the pros launch fireworks. If you're at home, use fireworks and sparklers under adult supervision and be aware of your local burn laws.

How Fireworks Work

The museum is open 10 a.m.–5 p.m.. Plan your visit and buy tickets at childrensmuseum.org

Saturday Science: Sugary Snot

Saturday Science: Sugary SnotIt’s a little gross, but it’s a lot of fun! In this Saturday Science, courtesy of Science Kids, you'll learn about the important role mucus plays in our body—by playing with fake snot!

 

Materials:

  • Boiling water (Have a parent help you with this.)

  • A cup (Choose a cup that can withstand boiling water.)

  • Gelatin

  • Corn syrup

  • A teaspoon

  • A fork

 

Process:    

  1. Fill half of your cup with boiling water.

  2. Add three teaspoons of gelatin to the boiling water.

  3. Let it soften and then stir with a fork.

  4. Add ¼ cup of corn syrup to your mixture.

  5. Stir again with your fork.

  6. Look at the long strands of gunk that are forming.

  7. As the mixture cools, slowly add small amounts of water.

        

Summary:

Does your sugary snot look … snotty? Yuck!

 

What makes your mixture look so gross is the combination of sugar and protein. Like real mucus, when you combined a sugar (corn syrup) and a protein (gelatin), you produced long, fine strings of goop. These strings are sticky, stretchy protein strands. Mucus uses these strands to  protect your body from contaminants (like dust or bacteria) by trapping the particles and carrying them out of the body and into your tissue.  

 

Want more Saturday Science? See all of our at-home activities on the blog or on Pinterest.

 

The SciencePort Scoop: School Is Out, but Science Is In!

SciencePort fossilsHeather Gromley is The Children's Museum's MuseumPort Coordinator. Heather is finishing her master’s degree in Museum Studies from The Johns Hopkins University. She enjoys planetarium shows, facilitating science programs, and sitting sidesaddle on giraffes on the carousel. 

The staff of SciencePort invites you to visit our space to put your science skills to work and investigate some pretty cool topics. SciencePort® is a great place for the whole family to dive and explore through hands-on activities and technology stations. We have everything from a microscope station, to nifty science apps and in-depth investigations. Each week, we feature a different topic, related to an exhibit in the museum. We feature activities on flight, plants, and health, just to name a few.

This summer we've launched investigation stations about China to support our extraordinary new exhibits Take Me There:® China and Terra Cotta Warriors: The Emperor’s Painted Army. Come explore tangram dissection puzzles, how to use an abacus, watch a live panda on the Panda Cam, create a Terra Cotta Warrior bookmark, and observe what tea leaves looks like under the microscope. 

SciencePort Dinos

One of our most popular programs is our Dinosaurs and Fossils theme. Together we'll decide what adaptations your dinosaur will need to survive in a setting you create. Will your winged T. rex survive in the ocean? Fossils are all around us, even in Indianapolis. Use the microscope or a magnifying glass to identify Indiana microfossils. Also, you can create a fossil imprint to take home with you! 

A cool feature of SciencePort is our animation station that allows you to make movie magic through stop motion animation. We also have touch screen computers and iPads to help you explore our topics.

Our super science staff is constantly researching new ideas for technology and investigations, so make sure you stop by each time you visit. We're located in ScienceWorks on Level 4. Look for signs around the red staircase in the construction zone area. SciencePort is open daily, from 11 a.m.–1 p.m. and 2 p.m.–4 p.m. Programming times may vary, so be sure to check gallery signs for more information about times or investigation topics. See you soon!