Sunday, November 18, 2012

This should have been a big success...

Jr. scientist E is obsessed with the moon. Every time my computer is out she asks to look at the pictures of the moon in our telescope gallery and she loves looking at the moon whenever it's out. So I've been excitedly waiting for the moon to be visible at a time when she'd be awake so we could look at it through the telescope. Tonight was finally the night. I set up the telescope, attached the camera so she could look at the camera screen instead of the much-more-difficult eye lens, and waited for the excitement. She was completely uninterested. I guess for a two-year-old the concept of looking down at a screen to see something up in the sky didn't make sense.

Monday, November 5, 2012

First planet sighting

We caught our first look at a planet through our telescope tonight. We were able to see Jupiter, along with it's moons (the picture doesn't do it justice). We weren't even sure it was a planet at first (and we didn't know which planet until we got home and looked it up - yes, we're very amateur astronomers). We noticed a big bright thing in a part of the sky where there should have been nothing bright, according to our star wheel. At first we thought it was an airplane, like all those bright "stars" we see that flash red and blue, but through the telescope it was clearly a beautifully round planet, surrounded by a diagonal line of moons (o.k., we didn't figure out that those were moons until we looked up pictures of Jupiter). It was a very exciting night.

Sunday, November 4, 2012

Stargazing

Since about the only thing in the sky that I can name is the moon, I decided to try to learn how to identify the various celestial objects. I found a great site for a print-at-home star wheel that shows the positions of the stars at different months and times of night and went out for a stargazing walk with Jr. Scientist A. After explaining to him what the star wheel did, he started pointing to every star he saw asking me what it was called. He's always been interested in outer space, but this was a level of enthusiasm that I rarely see. Although I'm sure my star and constellation naming was less than completely accurate (I'm pretty sure I labeled a few airplanes as stars), both Jr. Scientist A and I had a great time.

Homemade compass

We decided to build our own compass to help orient us for our stargazing. We magnetized a paperclip using our dangerously powerful- magnet (rubbing the paperclip across the magnet many times). We filled a container with water and put our now magnetized paperclip on a piece of cork in the water. The paperclip and cork slowly rotated until it was oriented north-south. We spun the cork around multiple times and it kept re-orienting itself. Pretty cool to see this invisible force at work (although next time I'll use a round piece of cork so it doesn't get stuck on the edge of the container without being able to turn). Jr. Scientist A liked the experiment, but I have a sense that the underlying concept of the earth having a magnetic field was a little too advanced.

Tuesday, October 16, 2012

Why does yeast make dough rise

Jr. scientist A often asks why we add different ingredients when we cook and one of the common ingredients we use (since we make a lot of pizzas) is yeast. I decided a while back to try to give a better answer than my standard, "yeast makes dough get bigger" response. I knew that there was carbon dioxide being released that formed little pockets in the dough, thus expanding it, so I thought we could do an experiment where we use yeast to blow up a balloon. Originally I put some yeast and water in a bottle and covered the mouth with a balloon. We checked on our experiment the next morning to find a still deflated balloon. I tabled the experiment for a while and was poking around online and found I was missing a key ingredient - sugar. We re-did the experiment with two bottles. The smaller bottle had yeast and water and the bigger one had yeast, water, and sugar. By the next morning the bottle with sugar had a nicely bulbous balloon sitting on top of it. Thanks to some laziness, we discovered that the bottle without sugar did eventually make enough carbon dioxide to partially inflate the balloon, but it took a few days to happen.

Thursday, September 27, 2012

Levitating ball

This is one of those experiments that I've seen in a number of books and kept passing up because it seemed like one of those experiments that looks like they should work but never do. The idea is that you use a hairdryer to "float" a light ball in the air. It works using Bernoulli's principle (the same principle behind airplane flight) - the fast air moving around the ball creates an area of low pressure, effectively acting to hold the ball in a tunnel. We were flipping through one of our books and Jr. scientist A found that experiment and asked to do it. I reluctantly got out the hairdryer, pointed it up and placed it on cool air, and gently placed the ball in the air stream. I was more than a little surprised to see the ball just float there on a cushion of air. Then Jr. scientist E did the next logical experiment - she nudged the ball. It moved a little and then moved back on its own to the center of the air stream like it was attached to a spring. That really got her excited. We all had a lot of fun with this experiment.

Thursday, August 23, 2012

New telescope toys

We got some new equipment for the lab telescope - a moon filter to increase clarity and a camera mount to help us take pictures. We're still learning to use the camera mount, but jr. scientist A is having fun taking pictures and movies of the moon.

Tuesday, August 7, 2012

Expectations

Although we've had our fair share of "dud" experiments, some experiments, albeit technically successful, don't land with the jr. scientists. It seems that there is what I can only refer to as an expectation gap. The experiments that have the biggest wow factor tend to be those that defy expectations. I suspect this is why bubbles are so fascinating to young children, and for adults it takes the bubble-suspended-in-space experiment to make bubbles cool. Likewise, the realm of possible is considerably smaller for adults, and some things that are expectation-defying for adults are just normal occurrences for kids. The other night Jr. Scientist A, myself, friend-of-the-lab David, and visiting Jr. Scientist S went to a mars rover landing party. As the rover landed on mars and sent back the first photos, the adults made a valiant effort to convince the kids that this was a big deal and really cool. The excitement of the moment was somewhat lost on the jr. scientists, and I suspect that the muted reaction was related to Jr. Scientist A's question to me earlier that day asking if we could go to mars the next day. I guess when making a day trip to mars is part of your normal expectations, seeing a grainy snapshot from the red planet just isn't that exciting.

Saturday, July 28, 2012

Exploring the lunar surface

Since jr scientist A has quite an interest in outer space, we decided to investigate why the moon looks like it does. I ran across this experiment in Pop Bottle Science (yes, I know, this has nothing to do with pop bottles). We looked at some pictures of the moon with all its craters and I asked jr. scientist A where he thought all those bumps came from. He didn't have any idea so we got out a container and some flour and made a mock lunar surface. Then I rolled a piece of play-dough into a little ball and threw it into the flour resulting in a mock crater in our mock lunar surface. Jr. scientist A had lots of fun making craters and it seemed to really make sense to him. It was a great way to explain an otherwise difficult to conceptualize idea (I wish I could take credit for coming up with the experiment!)

Tuesday, July 17, 2012

Electromagnets

After previous unsuccessful attempts to make an electromagnet (and my clear deficiency in electrical experiments), we turned to my first science teacher, Dr. A, for a little help. After finding the right type of wire (who knew there's a lightly insulated wire labeled specifically for making electromagnets - well I didn't, but thankfully Dr. A did!), we quickly had our electromagnet up and running, complete with a light switch that turned the magnet on and off. Jr. Scientist A had fun flipping the switch on, picking up metal objects like paperclips and silverware, and then flipping the switch off and watching them drop. Some paperclips did get temporarily magnetized, making the dropping effect a little less dramatic and the concept a little less clear, but it was still quite a success.

Friday, June 15, 2012

Floating bubbles


This has to be one of the coolest experiments we've done. Since Jr. Scientist E loves bubbles, I've been trying to find some more bubbly experiments to do with her (although she never gets tired of watching baking sod and vinegar fizz, I sure do). I ran across a cool one where you create carbon dioxide by mixing baking soda and vinegar and then you use bubble mix and blow some bubbles into the container. Since carbon dioxide is heavier than the air inside the bubble mix bubbles, the bubbles go into the container and then come to a rest in mid-air (resting on top of the invisible carbon dioxide). The bubbles will pop if they hit the edge of the container, so you need to do this in a large container with a lot of baking soda and vinegar (ah Costco, the kitchen scientist's best friend). The effect is absolutely jaw dropping and both Jr. scientists A and E loved it.

Sunday, May 20, 2012

Playing with brains

Jr. scientist A was playing with a brain puzzle we have (yes, we have a brain puzzle). I picked up a piece and said "here's the cerebellum." Jr. scientist A picked up a different part of the cerebellum and said to me, "no, this is the cerebellum, it looks like a tree." I have no idea how he knew that!

Saturday, May 12, 2012

Engineer in training

What a difference a week makes. When we first got the circuit kit a week ago I was a little concerned that it would be too difficult for Jr scientist A to do much on his own (after all, it was marketed for kids twice his age). But after a few days of playing with it, not only is he able to manipulate all the pieces, but he's started making working circuits all on his own (he made the one in the picture without any help - note that he only put down the pieces necessary for the circuit). He's even starting to learn to use the diagrams in the manual to make circuits. He's still having trouble identifying short circuits, but it's been amazing to see how quickly he's picked up everything.

Friday, May 4, 2012

Playing (safely) with electricity

We got Jr. scientist A a snap circuit kit where we can put together different electrical experiments (the different parts of the circuits snap onto a board like Legos). He had lots of fun trying to put every piece of the kit on the board but I was eventually able to convince him to separate out the pieces needed for the "flying saucer" experiment (the little island of circuits in the middle of the board). After a little fiddling we launched the flying saucer by putting it on the motor, getting it going fast, and then cutting the power. The little disk flew up in the sky - it was pretty cool. Bedtime got pushed back quite a bit as we played with the new toy.

Sunday, April 1, 2012

Hypothesis testing

Jr. scientist A came up with a hypothesis and we decided to test it. He had discovered that the pump for his stomp rocket had a little nozzle that could be removed. He hypothesized that the nozzle, with its smaller opening, would result in less air being pushed out of the pump and thus the rocket would fly a shorter distance (personally I thought the smaller nozzle would result in greater pressure and thus a longer distance flight). We tested the hypothesis by setting up the stomp rocket and firing off rockets either with or without the nozzle in place. We marked each place the rocket landed - blue for with the nozzle and white for without. To my surprise, all three white lines (no nozzle) were farther than all three blue lines (with nozzle). This was a moderately well received introduction to rigorous hypothesis testing, but clearly a tad bit advanced for Jr. scientist A.

Baking soda and vinegar reaction without the vinegar

We found this reaction by accident. We decided to try to make baking soda crystals. Just like we've done when making salt crystals, we started with dangerously hot water so that we could dissolve a lot of baking soda into the water. To our surprise, when we dropped the first spoonful of baking soda into the water, it fizzed up as if there was vinegar in the solution. Thinking that I had grabbed a container that had a little vinegar residue in it, we marched on with our crystal experiment (standing a little farther back). Every time we added baking soda, we got another fizzy reaction, long past the point where any vinegar residue would have been used up in the reaction. It turns out that mixing baking soda into hot water does create carbon dioxide, just like when mixing vinegar and baking soda. Granted this was (unintentionally) not the safest experiment, but it's always fun to find a new fizzy reaction. Of course, Jr. scientist A had quite a lot of fun repeating this one.

Monday, March 26, 2012

Colorful cauliflower

We had some extra cauliflower so we decided to do a capillary action experiment. We filled a small glass with water and food coloring and suspended some cauliflower over it with the stem in the water. We let it sit out overnight and in the morning Jr. scientist A came bounding over to me shouting "the experiment worked!" Clearly a winner.

Tuesday, March 20, 2012

Noisy noisy balloon

I found a fun sound experiment where you drop a nut (the metal type) into a balloon and inflate the balloon. When you shake the balloon you can get the nut to circle around inside, making a neat whirring sound (thanks to the repeated pattern of the edges). Jr scientists A and E had fun playing with this one. Making the sound is clearly easy enough for a baby - Jr scientist E had no trouble making it go. The only downside is that the nut starts to make tiny tears in the balloon after a few minutes, resulting in an increasingly small (and less fun) balloon. Maybe we should start buying balloons in bulk.

Tuesday, March 6, 2012

The curious case of gak

We made a batch of gak - mixing cornstarch and water to make something between a liquid and a solid. Jr. scientist A had fun playing with it and making quite a mess. Jr. scientist E's reaction was very interesting. I dipped her hand into the gak slowly (making the gak act like a liquid) and then dipped her hand into the gak quickly (making it act more like a solid). She got a very curious look on her face when the previously liquid gak suddenly seemed solid. I think it dawned on her that something surprising was going on. It was pretty neat to see.

Sunday, March 4, 2012

Jr. scientist A's experiment

A day after the anti-gravity pepper experiment where we used electrostatic charge to draw pepper to a balloon or plastic spoon, Jr. scientist A came up with a new experiment all on his own. He decided to try to catch light by rubbing a spoon against his head and holding the spoon near a light. He was off on a couple of details from our previous experiment (the spoon needs to be plastic and it only works with very light objects that can build up a charge), but it was definitely the most sophisticated experiment he's come up with to date.

Friday, February 24, 2012

Anti-gravity pepper

I didn't expect this to be such a cool effect. We put some pepper on a sheet of paper and then built up an electrostatic charge on a balloon by rubbing it against our hair (Jr. scientist A thought that was pretty funny). As we brought the balloon close to the pepper, the pepper became positively charged and started flying up off the paper and onto the balloon. As we held the balloon in place, more pepper kept flying up (and down) for a few seconds. It was so neat we kept repeating the experiment, trying to build up an electrostatic charge in different objects like plastic spoons (worked well) and cups (not so well). Jr scientist A and the senior lab members watched in amazement.

Tuesday, February 21, 2012

Parachutes

We decided to try our hand at making parachutes. Once again our brave gingerbread men rose to the occasion. Our first attempt used a coffee filter (nicely hyperbolic), and resulted in a slightly slowed descent. Jr scientist A came up with his own design (on the right), which worked better than mine (what does it say when a 4 year old can design a better parachute than you!). Jr scientist A wanted us to make parachutes for him and his sister, but I think such an endeavor might be a little premature.

Sunday, February 19, 2012

Hidden bubbles

We found this effect quite by accident. One of Jr. scientist A's new favorite things to do is to mix various ingredients together to see what happens - I think we have a budding chemist! We were adding things to red cabbage-dyed water (a pH indicator). As expected, when we added baking soda, the mixture turned blue, and adding vinegar to the same mixture caused it to bubble and then turn red. What caught us by surprise was that we next added salt and the mixture bubbled again. I had never heard of salt causing a chemical reaction resulting in bubbles, so we did some more investigating. Adding more salt turned the mixture from red (acidic) to purple, as would happen when you added a base, making us think that salt was a base (it's actually neutral). We tried combining vinegar and salt in another cup and got a rather unexciting cup of salty vinegar with no bubbles. After some google-ing, we found out that the salt wasn't actually creating bubbles, it was releasing the carbon dioxide bubbles trapped in our mixture after the baking soda and vinegar reaction. We decided to try adding salt to soda and got instant bubbles again. We even were able to create a little soda fountain (nowhere near as big as the mentos and diet coke reaction, but still cool). Jr scientists A and E both got quite a kick out of this accidental experiment, and I think it will become a new regular experiment.

Tuesday, February 14, 2012

Rafting

As a first step towards making an air- or rubber band-powered boat, we took some small pieces of corkboard and turned them into rafts (that is, we put them in a pool). Our brave gingerbread man once again sailed out to sea as Jr. scientist A made waves to get the raft to go to different ends of the pool. As for Jr. scientist E, she just giggled every time the raft sailed by her. An unexpectedly fun first step towards a bigger goal.

Tuesday, February 7, 2012

Water-crayons

Jr. scientist A wanted to do an experiment with swishing water in a bottle. We started out trying to make a tornado in a bottle where you tape two bottle caps together facing opposite directions and poke a hole through them both. When you attach the caps to two bottles (one with water) and swirl the bottles, you're supposed to get what looks like a tornado. Unfortunately, our tape didn't hold and we were left with two separate bottles with holes in the cap. So what do you do with bottles with holes in the cap? Make water-crayons of course! When you turn the bottles upside-down and squeeze, you get a steady stream of water that you can use to "draw" with. We had a lot of fun drawing shapes, people, animals, or just scribbling (Jr. scientist A also had fun "drawing" on my feet every chance he got!). What a fun accidental experiment.

Monday, January 30, 2012

Changing colors

Red cabbage juice is pretty cool. It changes color based on the pH of its environment. We got some dehydrated red cabbage juice powder in a science kit and decided to try it out. We mixed some of the powder and water in two cups, making some nice purple mixtures. We took our favorite acid and base (vinegar and baking soda, respectively) and added the baking soda to one cup and the vinegar to the other, getting bright blue and red mixtures (shown in the picture). Jr. scientist E was not impressed by the color changes, but Jr. scientist A really got into it. He immediately came up with a list of items to add to the mixture. We added baking soda to the vinegar mix, turning it back to purple (after the bubbles subsided). At Jr. scientist A's insistence, we added lemon juice, orange juice, flour, coffee, nuts, and various other things we had on hand - not a pretty mixture in the end but quite a crowd-pleaser!

Saturday, January 28, 2012

Separating colors

This experiment came from friend-of-the-lab Sandy. The goal of the experiment was to show that black is made from a mixture of colors. We put a long strip of paper in a bottle so that the paper went from the bottom of the bottle, up and out the top, and down to the table top. We filled the bottle part way with water and made a thick black line on the paper above the water level using a permanent marker. By the morning, our thick black line had turned into a smearing of colors. Although Jr scientist A would clearly have liked the black to separate before our eyes, the experiment clearly sparked his imagination and he's now asking to see what other colors are made of.

More moon-gazing

We've been spending more time looking through the telescope. Jr. scientist A noticed that around bedtime, the moon is in different spots in the sky on different days. Now that we're looking at a smiley-face crescent moon (I'm sure that's the technical term for that moon phase), he's noticed that the image we see through the lens is flipped compared to what he sees without the telescope. Still having lots of fun. Jr. scientist A likes changing back and forth between our two lenses to see the "close up moon" and the "far away moon."

Saturday, January 21, 2012

Peering into the microscopic world

Jr. scientist A just got a microscope (thanks Arthi and Glenn!), so we've been exploring the microscopic world. He instantly noticed that there was something very telescope-y about this new device ("it has a focus knob!"). As with the telescope, I wasn't sure how much he would be able to see through the lens, so we played the "what do you see" game. We looked at some string (top right photo), which he described as "branches" - a pretty good description. We also looked at colored sugar (bottom right photo), paper, grass, salt, sandpaper, and a few other things. Jr. scientist A had a lot of fun, but this was another one of those experiments where he had to compete with the adults for a turn!

Thursday, January 19, 2012

Paper boats

After some attempts to make floating canoes with paper and glue, which inevitably sunk when the glue dissolved, friend of the lab Arthi provided us with an origami paper boat. We sailed (and sank) our boat in the bathroom sink, much to the delight of jr scientists A and E. The experiment also turned into a surface tension experiment when our paperclip passenger stayed afloat after our boat sank. Remembering back to an old experiment, we added some dish soap and watched the paperclip plummet.

Wednesday, January 18, 2012

Stalagmites and stalactites, take 3

Never willing to admit defeat, we've made another try at making stalagmites and stalactites. We noticed that the area around our crystal experiments was covered with crystals. It seems that the salt water evaporated in the hot sun, but was too heavy to stay in the air and condensed out. We decided to take advantage of this to try to grow stalactites. We put a mesh (a cut-out from a screen door) on top of the jar for our latest experiment, hoping it would catch the escaping evaporated salt water. We poured our crystal making materials into the jar while it was covered by the screen so some of the liquid would stay on the screen and start a layer of crystals for the rest to hang on to. We weren't able to grow stalactites with this technique, but we got an unexpected but happy result. The evaporated salt water seemed to get trapped inside the jar so we ended up with one big thick crystal that covered the bottom of the jar. Pretty cool. I want to try this in a disposable cup next time so we can easily get the crystal out to play with. It looks like we'll finally have crystals that aren't to delicate to handle.

Thursday, January 12, 2012

Frozen boat

Inspired by an episode of MythBusters, we made a boat out of wet scraps of paper frozen together. We sandwiched the wet paper between two tupperware containers and put it all in the freezer. After it was frozen, we popped out the boat and set it to sail on the high seas of the bathroom sink with some brave gingerbread men, much to Jr. scientist A's delight. After a few minutes, the boat thawed and came apart. We put it back between the tupperware containers to re-freeze and sail again another day.

Friday, January 6, 2012

Moon-gazing

Jr. scientist A is really into outer space right now, and he got a telescope for the holidays. We weren't quite sure if he'd be able to look through the lens or understand what he was looking at. After a few times of me setting up the telescope and having him look at the moon, he decided he wanted to see some more earth-bound objects through the telescope. We started playing a game. I would aim at something familiar from across the apartment complex (like a decoration in his bedroom window) and ask him to tell me what he saw. He was generally able to identify what I pointed the telescope at - guess he was able to see through the telescope.

Going out to look at the moon (and some local objects) through the telescope has since become a nightly ritual. The only problem is that when there are a number of adults around, it's hard for Jr. scientist A to get a turn!

Wednesday, January 4, 2012

High flying fun

I swear there was a time when I could make paper airplanes that flew, but that time has clearly passed. So I got a book on making paper airplanes (recommended by friend of the lab Arthi). We were able to make a bunch of really cool airplanes (some of which actually took decent flights). Although I got this book for Jr. scientist A, I was surprised at how much fun the younger Jr scientist E had watching the airplanes fly by. She eventually started toddling over to where they fell and bringing them back for another flight. We had a lot of fun seeing how different designs and different modifications resulted in different flight patterns (I have to confess that I started making two of each design because I wanted more turns!). At some point, Jr. scientist A must have decided that the planes were flying because they were made of paper and insisted on trying to fly an (unmodified) paper bag. This isn't the first time that he's gone from observer/participant to actively guiding experiments in new directions, and I have to say I'm a bit proud of that!