27 Jul 2012

This post is just for kids!

If you are getting a little bored and want something to do, here's some science fun that you can eat. Make sure an adult helps you with this activity as you can get a nasty burn.

This is from Bubble Science

 Bubble Candy
There is a wonderful candy filled with bubbles that feels like an edible sponge on your tongue. When this amber-colored treat is covered with chocolate, it’s sometimes called Seafoam or Honeycomb. Grab an apron and an adult helper and make some bubbly candy.

You Will Need

a deep saucepot with tall sides

3 cups (750 mL) sugar

1 1/2 cups (325 mL) golden corn syrup

1/4 tsp (1 mL) salt

1 tsp (5 mL) unflavored gelatin

1 tbsp (15 mL) cold water

a small bowl

1 tbsp (15 mL) baking soda

a wooden spoon

a candy thermometer

10-inch (25-cm) square pan

butter or margarine

an adult helper

What to Do

The candy mixture is very hot and can cause serious burns. Make certain an adult uses caution when preparing the mixture. Do not touch the candy until it is cool.
1. Pour the sugar, syrup, and salt into the saucepot and stir to mix.
2. Have an adult place the pot on the stove and cook over medium heat. Stir the mixture until the sugar dissolves.
3. While the adult is busy stirring the mixture, place the gelatin in a small bowl and add the water. Stir to mix.
4. Prepare the pan by using a small amount of butter or margarine to grease the bottom.
 5. Have an adult use a candy thermometer to measure the temperature of the boiling syrup. When the candy reaches 290 degrees F (145 degrees C), have the adult add the baking soda, stir gently, then add the gelatin. Keep stirring and remove from heat.
6. Have the adult continue to stir the candy gently (so as not to stop the foaming action) for several minutes, then pour the mixture into the greased pan.
7. Let the candy sit until it is cool (at least an hour). To remove from the pan, place the pan into a larger pan of warm water. Make sure the water doesn’t get into the pan with the candy. Have an adult run a knife around the edges of the pan to loosen the candy.
 8. If you wish, you can melt chocolate and drip it over the candy. Store the candy in an airtight container.

What Happened

As soon as the baking soda was added, the mixture started bubbling. The bubbles were formed because the baking soda, a chemical called sodium bicarbonate, gives off carbon dioxide gas when it is heated. This gas becomes trapped in the heated mixture and forms millions of tiny bubbles. When the candy hardens, the bubbles make it really crunchy.

Bubbles in Food (sidebar)Bubbles can be found in all sorts of food. Take for example the "holes" in Swiss cheese. No, it isn’t a tiny mouse eating round sections out of the cheese. Cheese contains bacteria that give off carbon dioxide gas; as the cheese ripens, the gas forms bubbles. The cheese hardens around these bubbles, and that pretty much accounts for the holes. And now for some really interesting Swiss cheese trivia: The US government has regulations controlling exactly how big the holes, or "eyes," must be for Grade A Swiss cheese. If the holes are too big or too small, it can’t be called Grade A.

Bubbles in Soda

The next time you drink a carbonated beverage, take a close look at the liquid. You should see tiny bubbles rising from the bottom of the glass or bottle. Take a sniff over the top of the glass. Does your nose tickle? The bubbles rising from your drink contain a gas called carbon dioxide. It’s these bubbles that make your drink fizzy. Carbon dioxide gas is added under pressure when the soda is bottled or canned. When you open the container, the pressure drops and the gas can’t stay dissolved in the soda so it comes out. Warmer soda doesn’t hold as much gas as cold soda so if you want to keep that fizzy feeling, you need to drink your soda cold. Then, when it warms up in your mouth, the bubbles will form.

20 Jul 2012

I like lichens!

By Claire Eamer

Lichens add colour to a stone wall.
Have you ever noticed big splotches of white, green, or even red and orange on rocks and tree trunks? The white ones look a bit like bird poop, but they aren’t. (Well, actually, they might be – so look closely!)

Mostly, those splotches are lichens. And they’re actually pretty amazing.

To begin with, lichens aren’t one thing, but two. As the excellent guidebook Plants of Northern British Columbia puts it, lichens are fungi that have discovered agriculture. The basic structure of the lichen is provided by a fungus, a relative of mushrooms and puffballs. That structure is a kind of factory, filled with willing workers. Inside each fungus factory is a colony of algae, and that’s what creates the lichens’ sometimes-garish colours.
Lichens on an ancient standing stone.

Colour isn’t all the algae contribute. Safe inside their fungus, the algae work away at what they do best: converting sunlight into carbohydrates, vitamins, and proteins through photosynthesis, the same process plants use. The fungus, which can’t produce its own food, takes a share of what the algae produce as a kind of rent.

The arrangement works so well that the fungi and algae are inseparable, so they go under the single name of lichen. The kind of relationship the two partners have is called symbiotic, which means neither partner dominates the other and the arrangement benefits both of them.

The splotchy lichens (like the lichens on this ancient standing stone in northern Scotland) are just one form, called crustose or crust lichens. There are also lichens shaped like overlapping scales, and others shaped like curling dried leaves, miniature bushes, tiny clubs, or even fine hair. The floor of the boreal forest, which stretches across much of Canada, is so littered with lichens of all shapes and sizes that it’s sometimes called a lichen forest.
Lichens in the Yukon forest.

All those shapes, sizes, and colours have led to some pretty entertaining names. Spraypaint lichen, dog’s tongue lichen, chocolate chip lichen, and toad pelt are just a few. And there are plenty more. About 14,000 species of lichen have been identified so far, and there are still thousands more to find and describe.

Interested? Here are a few links:

A general online guide to lichens.
Ebook guide to lichens in Canada’s west coast forest
Ebook guide to lichens in Canada’s mixed hardwood forests.
And for lots of information about lichens, as well as some beautiful photos, The Lichen Guide.

13 Jul 2012

Arizona Meteor Crater

by Joan Marie Galat

Next time you make travel plans, trying searching the name of your destination with the word ‘astronomy’ and see what appears. You might discover a new science center, observatory, planetarium, or if you are very lucky, one of Earth's 150 meteor craters!

The best preserved impact crater is the Barringer Meteorite Crater in Arizona. Known simply as Meteor Crater, it is located on private land on the Southern Colorado Plateau between Winslow and Flagstaff.  The crater's rim rises up to 60 metres (196 feet) above the surrounding plain. The hole is 1.6 kilometres (1 mile) across, four kilometres (2.4 miles) in circumference, and more than (180 metres) 590 feet deep!

The Holsinger Meteorite is a fragment of
the asteroid that created Meteor Crater in Arizona 
About 50,000 years ago, the crater formed when part of a nickel-iron asteroid struck the desert. Travelling 26,000 miles per hour (almost 42,000 kilometers per hour), the approximately 100,000 ton rock hit with the force of more than 20 million tons of TNT! In only a few seconds, the blast moved 175 million metric tons of rock.

Scientists use the site to study how meteors impact planets, as well as to train astronauts and test robots.

The crater is located on privately owned land, however an on-site visitor centre offers excellent guided tours. You will also enjoy the large theatre, interactive exhibits, and observation telescopes. 

5 Jul 2012

Paddling the Ice Kap

No, I didn't get up North or to Antarctica, to paddle my kayak at either of the actual ice caps. Instead I got to try out a kayak model called the Ice Kap, from Sterling Kayaks. It was a great day to learn more about kayaking science. Yes, there's science in kayaking! There are all the measurements, when designing and constructing boats. There's also research. Which boat shape is good for racing, or for surfing in waves? And then there are the experiments. No lab coats and clipboards for me -- I just try the different boats and have fun, while my friends Louise and John keep a notebook of their own experiments with kayaks.

At the MEC Paddlefest on Willows Beach, we found an assortment of several models from Sterling Kayaks. Each is a custom job, with the foot pedals set to accommodate the paddler's own leg length, for example. I got to sit in an Illusion, but even with the footpedals adjusted as far as possible, my feet still couldn't reach. That would be no problem if I owned one of their kayaks, explained the designer, Sterling Donaldson. He would put the footpedals closer to the seat for someone as short as me. He's calculated the centre of gravity and balance points for all his kayak designs.

Donaldson gets fibreglass under his fingernails and epoxy all over his hands, he complained at one point. But there's no substitute for the hands-on approach when customizing a kayak for someone with special needs.

The foam seats are a terrific support... lifting the knees a little and fitting around the butt. I'm guessing that my partner Bernie would find THIS seat doesn't hurt his back. The seat back is good support, but low so that a paddler can lean back when rolling the kayak. On each side of the seat is a support for foam padding, to customize the fit to the paddler's thighs.

I got into the Ice Kap which is designed for small people. The coaming, the edge around the cockpit opening, is low. As in half-way up my thighs when I'm seated in the kayak. No more rubbing my elbows on the coaming with each stroke! That happens in most kayaks for me. The designer Donaldson pointed out, most shorter people are not only short in the leg, but have short backs as well. It's hard to roll a kayak that is too big.

My friend John Herbert  took a photo of me on the water in the Ice Kap. It's pretty clear in the photo that this boat has a lot of rocker, a curve which brings the keel up in the bow and stern. That makes for a lot of fun riding waves. I expressed some concern about the front deck being so high out of the water, and the stern so high. Wouldn't they catch wind and turn like a weather vane? "None of our boats weathercocks," Donaldson insisted.
The Illusion has a similar hull to the Ice Kap, but the coaming rises a little higher at the paddler's thighs and sides. John could tell that he wouldn't fit either model. At 6'4", he went for their Grand Illusion that fits the 6'3" designer. But the model on the beach had been padded to fit a thinner paddler. Not for John today!
Louise tried the Ice Kap as well, just to add another model to her research for which style of boat she would buy this summer. We compared notes. Afterwards, John and Louise changed out of their paddling clothes while I just wandered around evaporating. One of the most important things I learned about kayaking science is to wear clothes that evaporate dry quickly.
Our verdict: if you're a thin, short man or woman who is wanting an exciting kayak, try the Ice Kap for an experiment of your own. If you're not thin, try the Illusion as the coaming is just a little higher instead of pressing on the sides of your thighs.
And if you're a differently-able paddler (like every member of our paddling group, and plenty members of SISKA and VCKC and the entire crew of the Breaststokers Dragon Boat team), talk to a kayak designer about kayak science. How can a kayak meet your needs?
This particular designer understands. Sterling Donaldson not only talks the talk, he walks the walk with one leg and crutches on the beach among his kayaks. He grew up designing experimental aircraft with his father, and now he applies the scientific methods he learned to building kayaks.