This Blog's History: The Asteroid Belt Misconception

This Friday in This Blog's History I bring back to you a classic astronomy misconception regarding our solar system's asteroid belt.  Many people think the asteroid belt is so filled with asteroids that you have to duck and dodge your way through to survive.  Not exactly.  Turns out that individual asteroids are still millions of miles apart.  There's a larger concentration of asteroids in the belt than anywhere else in the Solar System, but the distance between any two asteroids is so large that you don't have to worry about a collision.

For complete details, see the original post.

Asteroid Belt Misconception

Steps vs. Height Experiment

A week ago my daughters and I did a simple experiment to determine if there was a correlation between a person's height and the number of steps a person takes to travel a specified distance.  Our hypothesis was yes.  Taller people have longer legs and can travel a farther distance per step than a shorter person.  To test this out, we each walked from the front of the house to the back, counting our steps.  Here are our results graphed.

I plotted our heights versus the number of steps it took.  As expected, the greater the height, the fewer the number of steps. As you can see from the graph above, the 3 of us had a close correlation between the number of steps and height.  We then tossed my wife into the mix, used the above data to predict her height based on steps, and found she was 4 inches too tall!  So not a perfect correlation but it was a fun activity to do with the kids.  It was fun discussing with them and seeing their faces as they thought through reasons why Daddy takes less steps to reach the back of the room!

Which Comes First: Science or Art?

The other day I was listening to an interesting episode of StarTalk Radio, hosted by Neil deGrasse Tyson.  In it he was having a discussion with his co-host on which comes naturally first in a child:  science or art?  It's an interesting question that doesn't necessarily have a correct.  Tyson argued that science comes first to a child because children are naturally inquisitive.  They dig into things and explore because it interests them.  Art can come early, but science is there from the very beginning.  Even young babies are exploring with their senses.  They look around.  They grab things.  They put everything in their mouth!  They are doing science through experimentation!

I tend to agree with Tyson on this.  Although my daughters love art now and are always painting and drawing pictures, their lives started with a love of science.  They didn't know what science was at the time, but they were constantly seeking out and discovering new information in their lives using their senses.  That's science!

Watching Movies in Bed

Toss this one into the category of perfectly acceptable to do on occasion.  We've developed a family ritual in our house of spending either Saturday or Sunday morning in bed together watching a movie.  All 4 of us cuddle up, make some popcorn, and watch a family friendly movie.  Do the kids get popcorn all over the bed?  Yep, they sure do!  Do we have to wash the sheets and vacuum up the popcorn pieces?  Yep, we sure do!  Is it worth it to spend family time cuddled up together?  Yep, absolutely!!!

What Happens to Hot Water Thrown in Cold Air?

With the cold weather across much of the U.S. this winter, many of you have probably seen the videos of people tossing hot water through very cold air and watching it never reach the ground.  Here's one example:

Hot Water in Cold Air

For most of these videos there's nothing incorrect about what's happening, but many details are left out.  For starters, why is hot water needed?  If you use cold water or don't heat the water to near boiling, the water will simply go up and then fall back to the ground.  One thing that happens with hot water is evaporation.  Some, although not all, of the water evaporates.  Thus what is left is a lower volume of water.

Second, why doesn't the water freeze into an ice cube?  And again, why is hot water necessary?  Shouldn't this work better with cold water since cold water is closer to the freezing point?  The properties of hot water are slightly different than that of cold water.  Hot water is less "sticky".  I realize this isn't the best term to use, but by less "sticky" I mean that hot water more easily breaks up into tiny droplets, whereas cold water tends to stay in a larger clump.  When the water is in a larger clump, it doesn't have time to freeze before striking the ground.  Hot water, however, does break up into tiny droplets.  Each droplet is of very low volume and freezes into a snow like substance, thus producing the cloud you see in all of the videos.

So again, it's not as if the videos are incorrect in what they say, they just aren't telling the whole story.

This Blog's History: Finding the International Space Station

This Friday in This Blog's History I bring back to you a post on finding the International Space Station (ISS) in your sky.  Although the ISS isn't producing light, sunlight reflects off of it back to the Earth, allowing you to see it in the night sky.  You just have to know where to look.  This is a great activity to do with your kids and you won't regret it when you see the amazement on their faces when they see the ISS for themselves!

Finding the International Space Station

Life to Her Years Update

Many of you are familiar with the Life to Her Years blog.  If not, definitely check it out.  Each post usually contains a picture of a dad and a daughter along with a caption.  As a dad, it really makes me think about my life with my daughters.

Anyway, the author of the blog is getting ready to publish a book, to be released in stores May 1.  The author is asking for help to spread the word and looking for people to be part of an advance team.  I offered my services.  If you're interested, check the today's post for details.

Life to Her Years Advance Team

Skeptic Magazine

I've posted previously about teaching your kids to be skeptical and demand evidence to claims.  A claim without evidence is pseudoscience.  I pointed readers to several podcasts that regularly focus on skeptics and skepticism.

Be Skeptical
Be Skeptical II

Here's another great source for you:

Skeptic Magazine

Skeptic Magazine is a great source on skepticism covering a wide range of science topics.  An absolutely excellent magazine.  It's published quarterly, so you're not overwhelmed with too much reading.  The other cool thing about Skeptic Magazine is that it has a Junior section at the end of every issue.  It's not written for young kids, but if your child is in middle school or high school, the Junior section is excellent.  For example, the Junior section of the last issue focused on Velikovsky, a very smart man who believed that biblical events can be explained by several close encounters by Venus.  The article uses science to explain why this isn't possible, written at a level for middle/high school students to clearly follow.

Check it out!

Mythbusters on Netflix

I've recently posted about watching Mythbusters with my 6 year old.  Imagine my excitement when I discovered that all past seasons of Mythbusters are available for streaming on Netflix!  Woohoo!!!  The other day we sat down and started the series from the very beginning.  During the first episode my daughter turns to me and says:

"Daddy, I love watching Mythbusters with you.  We get to see all sorts of science experiments that we can't do here.  Like explosions!"

LOL!  Yes, no explosions in the house.  As much as I'd like to blow up a toilet, it's probably not a good idea!

Ice Cream for Dinner

Let me be absolutely clear that I'm not saying it is okay for you to feed your child a diet of ice cream.  I'm simply saying that sometimes it's okay to break the rules...on rare occasions.  Let me explain.  Recently my wife had my 6 year old and I had to pick up my 3 year old from daycare after work.  It had been awhile since I had an opportunity to have an outing with just my 3 year old and I.  Although it was a bit too close to dinner for an ice cream snack, I decided, what the heck, who cares, it's a rare occasion.  So at 5-5:30 PM, I took her out for ice cream.  Granted, she didn't each much of a dinner later, but breaking the rules once in awhile is okay.  Your kids will thank you!  My 3 year old loved going out of ice cream and the smile on her face made the lack of eating much of a dinner well worth it!  Just be sure to not make ice cream dinners a habit.  Once every couple of months?  Sure.  Once a week?  Eh...probably not.

This Blog's History: The Pizza Box Oven

This Friday in This Blog's History I bring back to you a very cool science experiment that you can keep in store for a hot summer day:  The Pizza Oven Box.

The next time you order a take out pizza, you can re-use the box as a mini oven to cook something.  We cooked chocolate banana splits with ours!

For full details, check out the original posts:

Pizza Box Oven
Pizza Box Oven Success

Seeing Your Own Breath

It's quite possible that your kids will ask you (or have already asked you) why they can see their own breath at times.  As you're likely aware, it's very common to see your own breath when it's very cold outside.  Kids may think they are breathing out smoke or making some sort of cloud, but what's really going on?

When you breath out air from your lungs, there's a concentration of water vapor in this air.  The air that comes out of your lungs on a cold day is much warmer than the surrounding air.  The energy from the warm air transfers to the cold air.  The air that just leaves your lungs quickly drops in temperature.  As the air drops, the water vapor goes through a phase change from a gas to a liquid.  The water vapor changes into very tiny droplets of water.  These very tiny droplets of water, when viewed as a collection, look like a cloud of air leaving your mouth.

Although it would be more exciting if you could breath fire, that's not the case here.  It's a simple phase change of water from a gas to a liquid.

Is it Okay to Co-sleep with your Child?

Let me begin by saying that I'm completely against co-sleeping with a small child.  There's just too great of a chance of rolling over your child during the night and smothering him/her.  There's plenty of research out there on this that you can search for yourself.  As my daughters grew, I wanted to send a message that my bed is my bed.  I didn't want to send a message to my daughters that it was okay for them to frequently sleep in bed with Mommy or Daddy.  However, I don't think it's necessary to stick to this rule 100% of the time.  As long as your kids understand that they have their own bed, it's okay to let them sleep in bed with you on rare occasions.

So what are considered rare occasions?  For starters, thunderstorms.  I know that when it's stormy outside at night that I'll end up on the couch as my two kids wake up and worm their way between Mommy and Daddy in bed.  I have no problems with this.  I realize that loud thunder can be scary and it's okay if they want to cuddle up in bed with us.  I say us, but usually I end up going to the couch because my kids flop around like a fish and end up kicking me quite frequently.  :-)

Another rare occasion is when one kid is out of the house for the night.  My 6 year old daughter recently attended an overnight event with my wife, so it was just me and my 3 year old.  She wasn't happy that her big sister was leaving for the night, so I let her cuddle up with me in bed.  Again, it's such a rare occasion when this happens that it's perfectly acceptable to break the "sleep in your own bed" rule.

As long as sleeping in bed with Mommy and/or Daddy is set aside for rare occasions only, there's no reason to be super hardcore about sleeping rules.  Have a little fun once in awhile.  Your kids will thank you.

Is it Better to Walk or Run in the Rain?

Here's an interesting question that can lead to some quality science discussion between you and your kids.  Is it better to walk or run in the rain if you want to avoid getting soaked?  The initial answer may be to run.  If you're running through the rain, you are spending less time in the rain, thus reaching year destination faster and having fewer raindrops hit you.  On the other hand, as you run, you are more quickly running into raindrops that you are less likely to do if you are walking.

Hmmm....so which is best?  Do you walk or do you run?  It turns out that this isn't an easy question to answer and many different people have done scientific experiments on this.  My 6 year old and I recently watched an early episode of Mythbusters (first or second episode) where they tested this by weighing clothes after walking/running through the rain.  They concluded that walking through rain keeps you drier.  However, I discovered that they repeated this experiment (haven't seen this episode yet) and found that running through the rain keeps you drier.

There are many other studies out there as well:

Is It Better To Run Or Walk In Rain To Stay Dry? Scientists Say Run
Why You Should Run, Not Walk, in the Rain
Walk Or Run In The Rain? There's An Equation For That
Staying dry in rain: run or walk?

The results are all the same.  It's better to run than walk through the rain if you wish to stay drier, but it's not as clear cut as it may seem at first.

No More Santa???

I've mentioned before on this blog that I think this past Christmas was my 6 year old's last year of believing that Santa Claus is real.  I'm not even sure she really believed Santa Claus was real this past Christmas.  She's a very practical child, taking after her Daddy.  She's very good at analyzing the evidence available to her and arriving at a conclusion based on that evidence.  About 2 weeks after Christmas, while I was cleaning up the kitchen after lunch, she comes up to my wife and asks, "Mommy, are fairies real?"

My wife and I have had previous discussions preparing ourselves for questions such as this.  Telling your kids that Santa is real is a method of deceiving your kids, whether you think it's okay or not.  Had I done things over, I may or may not have led my daughter to believe in Santa.  I'm not sure.  But both my wife and I decided that once our daughter starts asking questions, we're not going to lie to her.

So when the "are fairies real" question popped up, we first asked our 6 year old, "Well, what do you think?"  Our daughter says "No, they're make believe.  They're not real."  We followed that up with a few "why do you think that" questions and then confirmed with her that fairies are not real.  Our daughter didn't specifically ask about Santa, but given that she's already come to her own conclusion that fairies aren't real, it's only one more step to come to the conclusion that Santa isn't real.

This Blog's History: The Floating Egg Yolk

This Friday in This Blog's History I bring back to you a classic density experiment.

The Floating Egg Yolk

By changing the density of water by adding salt to it, you can make the yolk of an egg float.  It all depends on whether the egg yolk has a greater or lesser density than the water.  Check the original post for more details and pictures.

Not My Type of Science Experiment

I love doing science experiments with my daughters, but there's a limit as to what I'm willing to do with them.  Here's the perfect example of what I'm NOT doing for a science experiment.  My wife, daughters, and myself are all in the kitchen dining room area the other night.  My 3 year comes up to me and says:

"Daddy, I have to go potty."

And off she heads.  She comes back a few moments later with a big smile on her face and says:

"Daddy!  Smell my hands!!!"

Uh...no.  I'm not smelling your hands knowing that you just went potty, and given you're 3, who knows if you actually washed your hands or not.  Plus, that smile is very mischievous!  Not taking my chances!!!

What Happens When a Can of Pop Freezes?

What happens when a can of pop freezes?  As the liquid inside the can freezes, it expands.  The frozen pop has nowhere to go so it pushes against the can until the can breaks and the contents fly out making a mess.  During the very cold stretch a couple of weeks back, we decided to test how long it takes a can of pop to explode in -12 degree F weather.  It took a surprisingly long time.  Sometime between the 2 hour and 2 hour 15 minute mark, the can popped.  We didn't notice right away until we looked out and the can was gone!  It had fallen off the deck railing and fell into a snow bank.  Upon fishing it out, this is what we found.

We then had a nice Sprite slushy!

On a related note, make sure to place the can far from the house.  I placed the can on the opposite side of the deck from the sliding glass door, but apparently it wasn't far enough.  The next day we noticed splatters of Sprite all over the door!

Center of Mass

The other day my daughters presented me with a great opportunity to teach them the basics of center of mass.  They have this Winnie the Pooh train they ride around the house on and on this occasion they tied a jump rope to hit and a play shopping cart to pull around the shopping cart while riding the train.  Unfortunately for them the cart kept tipping over.  The reason?  They tied the rope to the top of the cart.  Since the train is lower to the ground, whenever the train pulled on the cart, the cart was pulled downward and tipped.  I have the same problem with the hose on my vacuum cleaner.  The hose is attached to the top of the vacuum, so when I'm on the ground sucking up dust from underneath the bed, for example, pulling on the hose tips over the vacuum.  Ticks me off every time!

So I told my kids why it was tipping over and helped them find a better place to tie the rope, such as the bottom of the cart.

My daughters' geeky Dad saves the day once again!

Freeze a Bubble

It's likely that your kids enjoy playing with bubbles.  This is usually a summer activity and if your kids are like mine, they'll spend a good hour blowing bubbles and chasing them around.  However, this isn't just a summer activity.  There's a cool science experiment you can do with bubbles in the winter.  If it's particularly cold outside, the bubble mixture will freeze before the bubble pops.  We had some below zero weather a couple of weeks back, so one day we took the bubble mixture outside and tried to freeze a bubble.  To do so, first blow a bubble like normal and then catch the bubble on the bubble wand.  This may be difficult depending on the bubble mixture.  It was a bit windy out and the bubbles kept popping once they hit the wand.  For us, doing this outside was a failure, but we weren't defeated yet.  We came back in and caught the bubble on the wand inside where it was less windy.  We held the wand inside the freezer for a few moments to get our frozen bubble.  

The only problem with doing it inside is that the bubble mixture will quickly unfreeze once you pull it out of the freezer.  See our bubble less picture below.

There was a nice frozen bubble on the wand, but once we removed it from the freezer, it quickly unfroze and turned back into a liquid.  There's still a bit of frozen bubble mixture stuck to the sides of the wand.  

Give this a shot and hopefully you'll have better luck outside than we did.