Rarity of February 29 Birthday?

Having, or knowing someone with, a February 29th birthday is rare, right?  Actually, no.  February 29th comes around every four years during leap years.  This year, 2016 is a leap year, as was every 4 years prior to 2016.

Let's look at the rarity of a February 29th birthday.  Since February 29th only occurs every 4 years, one can reasonably estimate that the odds of being born on February 29th are four times lower than being born on any other day of the year.  This assumes that birthdays are spread equally across the year, which I will in this estimate.  During a non-leap year, an individual has a 1/365 (0.27%) chance of being born on a specific day.  Multiply this by 1/4 to get a 1/1461 (0.068%) chance of being born on February 29th.  Yes, it is lower, but not ridiculously lower to conclude February 29th birthdays are very rare.

How many people have February 29th birthdays?  The Earth's population currently sits at 7.3 billion, multiply this by the chance of being born on February 29th and you get approximately 5 million people with February 29th birthdays.  That's a lot!  In the U.S. alone, with a population of 319 million, we can expect around 220,000 people with February 29th birthdays.

What are the odds you know someone with a February 29th birthday?  Let's consider the average number of friends each facebook user has (338).  Multiply this by the odds of having a February 29th birthday and you find that a quarter of one person was born on February 29th.  Obviously one can't have a quarter of a person, but it shows that it isn't that unexpected to know someone with a February 29th birthday.  Add in the people you know who you aren't Facebook friends or people you know who don't have a Facebook account, and it's quite likely you do know someone with a February 29th birthday.

So is a February 29th birthday something to marvel over due to its rarity?  Nope.  Not at all.

This Blog's History: Talking to Your Kids About Cancer

For This Friday in This Blog's History I link you back to a post I wrote looking at the difficulty of explaining cancer to kids.  The original post comes with a cool video that explains a bit about cancer in way understandable to the average person not involved in the field of cancer research.

Talking to Your Kids About Cancer

Ant Farm Setback

I mentioned several days ago that my wife and I gave our 8 year old an ant farm for one of her Christmas gifts.  She was excited as was our 5 year old.  The ant farm doesn't come with the ants since the ants would not survive sitting in a box for who knows how long waiting for someone to pick it up and buy.  The kit comes with a voucher to order the ants for free from a supplier.  Cool!  Waiting a few days is no problem.  What I didn't consider was the typical weather during the winter season.

The supplier will not ship ants in the winter as long as there is a chance the temperature will drop below 32 degrees F for the obvious reason that the ants will likely die during shipping!  Bummer!  It makes sense, of course, and we don't want a vial of dead ants.  Still, it was a bit disappointing knowing we have to wait a couple of months before getting our ants for the ant farm.  

So, consider getting an ant farm for your child, but just be aware that you may not have ants right away depending on the season.  

Cooking at High Altitudes

Every once in a while you might be baking something and notice the baking instructions on the side of the box are modified if you live at high altitudes.  Why would the baking instructions of a cake, for example, differ based on your location on Earth?

The answer is air pressure.  Let's use the example of boiling a pot of water and cooking noodles.  You likely know that the boiling point of water is 100 degrees C (212 degrees F), but this depends on the air pressure.  The boiling point of water that we know as 100 degrees C is defined at sea level.  The higher your altitude, the less air pushing down on you and the lower the air pressure.  

At an altitude of 1000 feet the air pressure is about 97% of that at sea level.  At 2000 feet the air pressure is about 93% of that at sea level.  At 5000 feet, almost a mile above sea level, the air pressure is about 83% of that at sea level.  What does this have to do with cooking?

Consider a boiling pot of water.  To boil the water one needs to raise the temperature of the water enough such that the water turns into water vapor.  The water can more easily turn into water vapor if the pressure pushing down on the water is less.  Therefore, it is easier to boil water at higher elevations because the temperature needed is lower.  A higher temperature causes the water molecules to move faster.  With less air pressure pushing down, they don't need to move as fast to escape (become water vapor), and the water boils at a lower temperature.  

Once the water starts to boil, you can't increase the temperature any further.  If the water boils at a lower temperature and you dump your noodles in the water, the noodles are cooking at a lower temperature.  As a result, it will take longer to cook the noodles.

How much lower is the boiling point of water at higher elevations?  At 1000 feet the boiling point of water is 98.9 degrees C which is not much lower than the 100 degrees C at sea level.  Thus there is no need to change the cooking instructions at this altitude.  At 5000 feet, however, the boiling point of water has dropped to 94.9 degrees C which is significant drop.  Many people live at even higher elevations with even lower boiling points.  Therefore there is a need to adjust cooking times at higher elevations.  

SciShow Videos - YouTube

Looking for great YouTube video channels that share science?  I've shared a few already, but here's another great channel I subscribe to.

SciShow

Most of the videos are short, just a few minutes in length, which is great for those of us on a busy schedule but still want a few minutes now and then to learn some science.  The videos are interesting, exciting, and guaranteed to teach you something new.  I've yet to watch a video in which I didn't learn something new!

I encourage you to check out these videos and share this with your kids.  They'll love it too and you'll likely be amazed at the science they'll share with you after watching these videos.  That's the moment you know your kids are in love with science, when they seek out science learning experiences on their own and then share with you!

Green News Report

It's been awhile since I've shared a science podcast on this blog.  If you read this blog, you already know I'm a big fan of podcasts, especially science related podcasts.  I've shared several on this blog, such as Talk Nerdy with Cara Santa Maria, The Skeptics' Guide to the Universe, Star Talk Radio by Neil deGrasse Tyson, and This Week in Science.  Here's another one for you to add to that list.

Green News Report

The Green News Report is a short, 6-7 minute podcast usually published twice a week.  The hosts briefly share a few news stories related to climate change.  It's a great podcast to get the basics on climate change news, especially if you don't have much time to devote to podcasts.  We all have 6-7 minutes to spare twice a week!  I encourage you to check it out and share it with your middle/high school kids.

This Blog's History: Where Did the First Baby Come From?

A few weeks ago I shared a post of my response to my 5 year old asking about where the first human baby came from.  Not the easiest question to answer.  For This Friday in This Blog's History, I'm providing the link to the original post that has my response to my daughter.  Fortunately there are a number of fantastic books on basic evolution for kids!

Where Did the First Baby Come From

A New Planet?

You've likely seen this news already, but in case you haven't, astronomers have announced evidence for a 9th planet in our Solar System!  How exciting!  It's not every day evidence for a new planet comes about!  I'm being very careful about my wording here and not saying a new planet has been discovered but instead stating that evidence for a new planet has been found.  Those are two different things.  The evidence is strong, but needs to be confirmed and further studied.

The evidence supports a planet that is ten times the mass of Earth with a closest approach of 200 astronomical units.  The distance between the Earth and the Sun is defined as one astronomical unit.  This possible planet is about the size of Neptune, but much farther out.  Neptune has an average distance of 30 astronomical units.  This possible planet could have an elliptical orbit that takes it much farther out from the Sun.

Note that this planet was NOT imaged.  It's too far out to reflect enough light to detect with an optical telescope.  The evidence comes from gravitational tugs on the other dwarf planets that are already known.  Below is an image mapping the orbit of this possible planet.

This is an exciting discovery, but it's important to be cautious over declaring the definite discovery of a new planet.  The evidence looks strong, but more work needs to be done to change our textbooks.  Still, very exciting!!!

Gravitational Waves Detected!!!

You've likely heard this by now but it's such an exciting discovery that I can't help but share it on this blog.  Last week astronomers announced the first detection of gravitational waves!!!  Gravitational waves are ripples in spacetime produced by an object with mass, that move outward as waves.  Gravitational waves are a prediction of Albert Einstein's General Theory of Relativity in 1916, 100 years ago.  Until now, however, they have escaped our grasp in determines of a detection.  Today it was announced this has changed.

In addition to confirming Einstein's General Theory of Relativity, the detection of gravitational waves provides further evidence in support of the Big Bang Theory.  More experiments need to be done to confirm these results, but at the moment, they look very strong!  Awesome science in action!!!

Scientists Detect Gravitational Waves

Science Channel - YouTube Channel

Once a week, for the next several weeks, as well as the last two weeks, I'm sharing a YouTube channel that specializes in science.  Thus far I've shared ASAPscience, The Backyard Scientist, and Braincraft.  This week's science YouTube channel is the Science Channel.

The Science Channel is connected to the Discovery Channel on cable TV.  Several clips are from science shows on this cable network.  There are several themes, including 'How is it Made' and 'Outrageous Acts of Science'.  Basically these videos are trailers to the TV shows, but enough is shown to learn something from the YouTube videos.  

I encourage you to check it out and show your kids.  There are quite a few very cool videos!  For example, just the other day I learned how gingerbread house pieces are made!  Now I can share the background information to my kids the next time we are struggling mightily getting our gingerbread houses to stay standing!

Green Bean Experiment Results

Last week I shared the procedure for my daughter's Green Bean Science Experiment.  Basically she planted green bean seeds in different cups and watered each cup with different liquids.  Liquids used were water, milk, Powerade, Coke, and orange juice.

Somewhat surprisingly a green bean plant sprouted for each of the liquids as shown in the cups below.

The plants grew best in water, but every liquid worked!  Each day after the green bean plant sprouted she measured the height of the plant.

Awesome!  She had a blast doing this science fair project and is already looking to next year's science fair!  We also observed mold growing in the non-water cups as well as a very stinky smell coming from the milk cups!

This Blog's History: Why are Bridges Icy?

We haven't yet moved from winter to spring, so it's important to stay safe when driving in wintry conditions.  Bridges will ice over before the main road, so one must always be careful when driving across bridges in the winter.  Why is this?  For This Friday in This Blog's History I bring back to you my post on this from a few weeks ago.  The science is explained in that post.

Why are Bridges Icy?

The Where's Waldo Board Game

The Where's Waldo Board Game is a great activity for you and your kids on a rainy, snowy, windy, and/or too-hot day.  Shortly after Christmas break we had a cold winter day in which none of us wanted to leave the house to go anywhere.  Instead we popped out a few board games and had some afternoon fun.  Where's Waldo was one of the games my daughters grabbed.

I'll fully admit that this is a fun game!  There are nine game boards on which various images are hidden.  At a basic level, if you are the first person to find the object shown on a card, you win that card.  Person with the most cards at the end wins.  My daughters were definitely better than me as I had very few cards at the end.  I was trying to win too!!!  I wasn't letting them win!  So if you have younger, elementary aged kids, this is a great birthday or holiday gift idea that the whole family will have fun playing!

The Potato Experiment

My 8 year old is in the process of doing a potato experiment.  The goal is to test how quickly spuds grow on a potato in various conditions.  We started with several potatoes that all came from the same bag.

Full disclosure:  The above picture is not our bag of potatoes.  It's a stock photo.  Apparently I didn't take a picture of our bag of potatoes.  :-)

We next pulled out several bowls, putting one potato in each bowl.  Then my 8 year old put them in various locations around the house.  One potato went in the refrigerator.  One potato sat on the kitchen.  One potato was placed in a dark closet.  Another potato was placed in the bathroom.  One potato was placed next to the window, exposed to daily sunlight.  The final potato was placed next to the heat vent on the floor.  

So yes, we are the house that has a random potato in a bowl sitting on the bathroom counter and another sitting on the living room floor next the heat vent.  :-)

Check back soon for results...or not so soon as I'm not sure how long it will take for the spuds to appear!

The Backyard Scientist - YouTube Channel

Looking for another great YouTube channel that shares awesome science?  Look no further than The Backyard Scientist.

The Backyard Scientist YouTube Channel

This guy has a number of videos on do-it-yourself science projects he has literally done in his backyard!  Some of these are not kid-friendly in the sense that they can be dangerous, so beware.  The videos are awesome and show some very cool science experiments.  For example, here's a link to a video in which he mixed molten aluminum in water beads.  The result is super cool!

Molten Aluminum vs. Water Balls

If you have a few minutes to spare and are looking for some awesome science, then this is the YouTube channel for you!

The Green Bean Science Experiment

Last week I shared my excitement of my 8 year old's first science fair project.  I explained the basic procedure which is to test the growth rate of green bean plants "watered" with different liquids.  The germination time for these seeds is 7 - 14 days, and I'm happy to report that we are seeing results on Day 7!!!  Nothing was observed on Day 6, but the very next day we could see a tiny bean green plant just starting to poke above the soil.

The liquids used are water, milk, orange juice, orange powerade, and coke.  The water and orange powerade cups are showing green bean plants.

The labeled cup image shows the liquid used in the image just above it.  The images do not do this justice as it is very hard to see where the green bean sprout is at.  Trust me, it's in there.  Nothing was observed in the other cups on Day 7, but there are a few mold layers and the milk cup reeks!!!

And by reeks I mean it smells horrible!  All in the name of science!  Stay tuned for further results.  The next step is the measure the height of the bean green shoots each day to see if there are difference based on liquid used to "water".  

This Blog's History: The Importance of Science Advocacy

About a month ago I shared my thoughts on the need for continued science advocacy at all levels of society.  When people are misinformed on basic science, bad government policies are often the result.  For This Friday in This Blog's History I re-share this post with you.

The Need for Science Advocacy

With this being an election year, I  encourage you to investigate ALL politicians on your ballot and vote for those who promote high quality science.  Society cannot survive if we are ignorant of basic science.

Harry Potter and the Prisoner of Azkaban

My wife, daughters, and I continue our family activity of reading the Harry Potter books together.  We just finished the third book, Harry Potter and the Prisoner of Azkaban!  Another excellent Harry Potter book.  My wife and I have previously read the Harry Potter series, but this is the first read through for my daughters.  As with the first two books, we are following the third book by watching the third movie.  My kids LOVE the books and the movies.  We make an evening of watching the movies by making a nacho platter for dinner.  It's sort of a tradition, if by tradition you mean done three times.  :-)

The Harry Potter books become more adult themed, although still PG and PG-13 as the series continues.  This is first noticed in the third book.  As the characters age, they take on more responsibility and face greater challenges.  The books also become longer.  The first book was around 300 pages.  The second book is around 325 if I remember correctly.  The third book jumped to 435 pages.  The fourth book, which we'll start reading soon, jumps all the way to 800+ pages!  That's going to take a while to read, but we, as a family, are up for the adventure!

BrainCraft - YouTube Channel

Yesterday I shared a YouTube video on the basics of why so many people get cancer.  I pulled this video from the BrainCraft YouTube channel.  I've recently found myself checking out various science YouTube videos on different channels.  There are an amazing number of channels that produce very high quality science videos.  I plan on sharing several to this blog over time.  The first is BrainCraft.

BrainCraft YouTube Channel

In addition to the cancer video, I've watched several others and they are equally awesome!  Check it out and share this channel with your kids to watch on their own.  Knowledge will be gained, guaranteed!

Talking to Your Child About Cancer

All of us know someone, if not ourselves, who has had or currently has cancer of some type.  It seems that cancer rates are much higher today, but the exact cause is unknown and may likely be due to many factors.  There are many different types of cancer and many different types of treatment depending on the type of cancer.  At a basic level, cancer results from the uncontrolled dividing of cells in the body.  The older one is, the more likely one is to have cancer.  With increasing life expectancy, this may be one cause of higher cancer rates today.  There could be undetermined environmental effects as well.  

Given the prevalence of cancer in the world today, your child likely knows someone with cancer and has many questions.  Approximately 40% of people will have cancer at some point in their lives and 20% will die as a result of cancer.  Fortunately treatments today are far more effective than they were just a couple of decades ago.  If your not sure how to discuss the science of cancer with your child, I encourage you to watch this short YouTube video produced by BrainCraft.

Why Do So Many People Get Cancer?

This is a short, 6 minute video, that explains the very basics of cancer.  Obviously it doesn't get into the details and it isn't cancer-type specific, but for an introductory discussion on the basics of cancer, this video does a fantastic job.  

Like I said, we all know someone with cancer and anyone with kids knows that they ask many, many questions.  Sometimes we, as parents, don't have the answers and need help.  This video provides that help on this topic.  Cancer is a fact of life and something that is less scary when the facts are known.

First Science Fair Project!

I'm very excited to report that my 8 year old is participating in her very first science fair project and is super excited!  The science fair is done through her school and three projects at each grade level will advance to the regional fair.  We looked around on the web for projects that weren't too easy, but also weren't too complicated for her age level.  The goal is for her to do this project, not mom and dad.  The project she chose looks at the growth rate of green bean plants given different liquids.

We started by buying a basic pack of green bean seeds from the store.  The next step is to fill several same sized cups of potting soil.  We went with two different sized cups as a test to see if cup size has an effect.  Basically we are running the experiment twice.  Each cup was filled with exactly 1/3 cup of a liquid.  Liquids used were tap water, milk, orange juice, Coke, and orange Powerade.

My daughter will monitor the cups each day and record the first day a sprout appears above the soil line.  At that point, the height of the green bean sprout will be measured.  The goal is to determine if green beans grow best in water or a different liquid.  The germination time for these green bean seeds is 7 - 14 days, so nothing will happen for several day.  

This is an exciting time in our house.  Our 8 year old is super excited to be doing an official science fair project and is looking forward to the presentation night in about 3 weeks.  Hopefully she has some good results to show.  Even if the experiment does not work as well as planned, there's still much to be learned.  When things go wrong, it's not necessarily a bad thing in science as the disappointment can still lead to knowledge gained.  

If your child brings home a flyer about an upcoming science fair, don't ignore it.  Encourage your child to participate and search the web for ideas.  There are thousands out there!!!