29 May 2020

Fade to ... blue?

Back when the canoe was purple.
Fading: it sure can make things look old. Red patio umbrellas fade to pink; posters fade to monochrome; and twenty years after I bought my purple canoe, I found it was still shiny, but now it was blue! It totally changed colour. How is that possible?

Not all colours fade at the same speed. Red is the least stable, and blue seems to last longest. Why is that?

What Makes Colour & What Makes it Fade

Colour comes from pigment either naturally or by adding it. (Tulip colour is natural and paint has colour pigment added to it.) Air and sunlight break down the chemicals in that pigment colour, though, and so can the other substances the pigment is mixed with, like plastic. Sometimes a reaction creates oxygen, and that bleaches the colour too. Heat and humidity can speed this up; they tend to speed up all reactions.

Colour Wavelengths Matter

The longer the wavelength of absorbed light is (which causes the colour we see), the faster it will break down. Even the longest colour wave is stupendously small; you could fit almost 1600 wavelengths of red light into the width of a human hair.

This size chart of wavelengths on the elecromagnetic spectrum comes from the English Wikipedia (Original author: Philip Ronan) and is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.
Blue is in the 400 nm range of wavelength and red has much longer, weaker waves up in the 700 nm range. Red fades much faster than blue.
Grab your crayons or your paints and you will find that mixing blue and red makes purple. That is what my canoe builder did; she told me she mixed red and blue paint to create purple that could not be bought. Since the red part of the mixed paint degraded faster than the blue part, it resulted in a 20-year-old canoe that is blue.
The red faded from my purple canoe, leaving behind only the blue in the mixture after 20 years. The purple underneath peeks out after sanding.

Colour to Last 

If you were making something to sit outside in the sun for a long time, what colour would you make it? Look around you: Does it look like makers tried that? What colour are tarps? How about tents or sail covers?
To preserve cave paintings, we limit their exposure to light, heat, and humidity by limiting how many people can visit them. People bring heat with their bodies and humidity with their breath, as well as lights to view the paintings.

Colour to Go 

What if you wanted to get rid of colour? How could you use what you know about light and oxygen to bleach something?
piqsels.com License to use Creative Commons Zero - CC0
How are colour fading facts being used to get this laundry bright white?

22 May 2020

Did you know....?

By Claire Eamer

Have you noticed that the world is way too serious these days? I mean -- there are reasons why it's serious. I know that. But we can't do serious all day, every day. So here's some non-serious sciency stuff.

When I'm researching a new book, my family gets used to my wandering through the living room or sitting down to a meal and starting the conversation with, "Did you know...?" It means I've found another awesome, mind-boggling, who-woulda-thunk-it fact in my research. Some of those facts make it into the final book. Some don't. But I love them all. So here are a few.

When I was researching Out of the Ice: How Climate Change is Revealing the Past, I read about Ötzi the Iceman, the man who died 5300 years ago in the Alps and whose body lay frozen and preserved all that time, along with his travel gear. Which included socks! Somehow, knowing that a guy who lived and died so long ago wore socks makes him so much more real in my mind. And they weren't ordinary socks. He wore leather shoes stuffed with grass to protect him from the cold, and string socks to keep the grass in place.
Okay, it doesn't look much like a modern sock. But if you look closely at this
replica of the Iceman's footwear, you can see a kind of twine mesh sock
holding the insulating grass in place. The outside shoe had a bearskin sole
and deerskin upper. This replica is in the Bata Shoe Museum in
Toronto, Ontario.
Speaking of socks, here's another sock-fact I learned -- this time while researching What a Waste! Where Does Garbage Go? Roman soldiers wore socks! Inside their sandals!!

Here's the handle of a Roman razor, made in the form of a foot wearing
a sandal and sock. The rolled top of the sock is part way up calf, and, if you
look closely, you can see a herringbone pattern in the sock. That shows it was
probably made of woven material, not knitted yarn.
Photo by The Portable Antiquities Scheme, Philippa Walton.
When you think about it, that makes sense. Not every place the Romans went was as sandal-friendly as central Italy. At the Roman fort of Vindolanda in notoriously cold and wet northern England, an ancient rubbish dump revealed the truth. Almost 2000 years ago, someone in a Roman soldier's family (his mother?) sent him a care package containing -- as recorded in a letter that is still legible -- two pairs of sandals, two sets of underwear -- and socks.

Here's why that Roman soldier wouild have been grateful for warm socks.
He almost certainly spent time on duty at Hadrian's Wall, just north of
Vindolanda. Even on a fine, warm day like this, it's a rough and exposed
place. But in winter, with the cold and the rain and the wind...? Socks
would be very welcome. Claire Eamer photo.
Both those sock facts made it into their respective books, but just in passing. Maybe I need to write a book about socks? Okay, maybe not. But maybe a book about Indian Runner Ducks? They are weird! They stand upright, like penguins, and instead of waddling like your average duck, they can run.

Here's a little family of Indian Runner Ducks. They're sometimes called
bowling pin ducks or penguin ducks, and you can see why.
Photo by Alan Rockefeller - Own work, CC BY-SA 4.0,
Runner ducks come from the East Indies, from some of the islands that now make up Indonesia. They're good egg-layers and good walkers -- which means they can be walked to market, rather than carried. They don't need water as much as most ducks, and their wings are too small for flying, so they are fairly easy to keep. But you've got to admit, they're a bit silly-looking!

And why my sudden interest in Indian Runner Ducks? I think it's related to the fact that there are currently seven Indian Runner Duck ducklings living in a basket in our laundry room. I'm looking forward to watching them race around the yard like speedy penguins in a few weeks.

Here -- have a duckling picture. If that doesn't cheer you up, I don't know what will.

Claire Eamer photo

15 May 2020

Science Books for Kids

 book reviews by Margriet Ruurs

What is science?
The dictionary defines it as:

sci·ence -
/ˈsīəns/ the intellectual and practical activity encompassing the systematic study of the structure and behaviour of the physical and natural world through observation and experiment.

There are many different kinds of science: technology, biology, physics… And possibly the best way to learn more and to find out which type of science most appeals to you, is by reading books.

Science books are as varied as the branches of science themselves. Many of the contributors to this blog are writers of books or articles about science. Here is a list of recent, and not so recent, titles that I love:

Back Holes and Supernovas by Joan Marie Galat, Capstone Books, ISBN 978-1-4296-7225-2, is a fascinating read about the lives and deaths of stars and the black holes they leave behind. Full of interesting facts and photos.

50 Climate Questions, A Blizzard of Blistering Facts.
Written by Peter Christie and illustrated by Ross Kinnaird, published by Annick Press, ISBN 978-1-55451-374-1.
This book is divided into different topics. Each page starts with a question, all to do with climate change. Questions about volcanoes, ancient civilizations, electricity and much more. Besides answers, there are text boxes with additional information as well as a few activities. The illustrations almost turn this book into a fun graphic novel.

One of my favourite science books is The World in your Lunch Box, The Wacky History and Weird Science of Everyday Foods, written by Claire Eamer, illustrated by Sa Boothroyd and published by Annick Press, ISBN 978-1-55451-392-5.
What a cool idea to look at the history, mystery and facts of food by looking at what’s in most people’s lunch boxes. The history of pizza, what kind of eggs can you eat, why are hot dogs called hot dogs, how did we get spices? A great book for anyone who’s ever… well, eaten anything.

Philippe Cousteau is the grandson of the famous Captain Jacques Cousteau who brought us awareness of oceans, its wildlife and water pollution. Philippe and Cathryn Berger Kaye, an educator, wrote two books together:

Make A Splash! ISBN 978-1-57542-417-0 is a kid’s guide to protecting oceans, lakes, rivers and wetlands. Full of facts and photos, the book shares information on such topics as over-fishing, trash, keeping rivers clean, wildlife and much more. But most importantly, it gives many examples of how kids can make a difference. It offers solutions to many problems and helps kids to become environmental activists.

Similarly, Going Blue ISBN 978-1-57542-348-7 by the same two authors, is aimed at teens.
Tackling trash, water shortages, coral reefs - every aspect of water - this book also offers solutions and doesn’t just state problems. There are many examples of young activists from around the world who are making a difference.

And finally some fictional reads with a science twist. When are animals really extinct? The last one touches on sci-fi. Or does it?

Music for Tigers by Michelle Kadarusman, published by Pajama Press, ISBN 978-1-77278-054-3, is fiction does have to do with environmental protection and species going extinct. This is a realistic story about a girl who visits a relative in Tasmania. There she learns about the environment and about an elusive animal that is occasionally spotted. Could it be the Tasmanian Tiger, believed to be extinct? After I finished reading this novel, I searched the topic online and discovered that, indeed, many sightings are still being reported. So perhaps Tasmanian Tigers are still living in deep, dark corners of their habitat….

And finally a book that walks a fine line between fiction and science fiction: Elephant Secret, by Eric Walters, published by Penguin Random House, ISBN 978-0-7352-6281-2
In this story, Samantha and her dad run an elephant sanctuary. They face financial troubles and fear that they might not be able to protect the elephants any longer. Until a new elephant baby arrives that seems both adorable and strange. The baby arrives at the same time as a mysterious investor. In this riveting novel, Samantha learns about cloning and wonders if, perhaps, she is raising a wooly mammoth instead of an elephant.

8 May 2020

Scientists and Engineers: Partners in Problem Solving

Even rubber ducks are products of engineering.
by Joan Marie Galat
When it comes to problem solving, science and engineering represent a partnership. Scientists explore and observe the world and conduct experiments to improve their understanding. Engineers look at circumstances and try to make life easier using the principles of science and math. Across the centuries, engineers have used their knowledge to create tools, machines, and structures. They've also helped create everyday objects from water-squirting rubber ducks to the screen in front of you.

When I was writing Solve This! Wild and Wacky Challenges for the Genius Engineer in You (National Geographic Kids), I came across many kinds of science and engineering partnerships. Despite having plenty of pages to work with, I couldn’t fit them all in! Here’s a few "not in the book" examples of science and engineering that led to new products.
  • In 1943, an engineer was experimenting with ways to use springs to cushion the movement of instruments on ships. His prototype became the Slinky!

  • Play-Doh was meant to be a wallpaper cleaning product. Things changed when kids discovered how fun it was to shape. The company removed the cleaning chemical and added scent and color. Thanks to science and engineering, we have irresistible Play-Doh. 
  •  X-rays, which exist in the natural world, were discovered by a scientist experimenting with cathode rays. The detection of
    light particles passing through objects later allowed engineers to invent x-ray machines. 
You can find more examples through NBC News

Try partnering science and engineering yourself! Here’s a few activities to get you started.

Don't Steal My Candy!

Use Engineering to Make a Coin Sorter

Look for more connections to science and engineering in Solve This!

1 May 2020

Home Science Project: making circuits with play dough

by Paula Johanson

Today's post is a short one, but will be fun for anyone playing at home making electric circuits. If you are learning about how to make projects that light up, or buzz, or move, you probably already have what you need. Click here for a link to a website discussing popular kits for kids to use making electric circuits. There are many places you can find online where families can buy and have delivered by post a kit, full of electrical parts that are safe to use when following simple instructions.

But you might also have another useful material at home for making circuits for models or toys or science projects. Did you know you can make play dough that conducts electricity? And you can also make play dough that insulates, so no power is conducted? All you need to make either of these doughs are ordinary food ingredients for baking cookies.

Check out the website at SquishyCircuits.com by clicking on this link. On their website there are tutorials and instructions. Though they sell packages of electrical parts and play dough, they also have play dough recipes for free download. As with any science project, it's important to be safe. Beginners and younger kids will need adult supervision.