"Want me hit you with a bolt of lightening?"

 

"Want me to hit you with a bolt of lightening?"

Think about that question for a second what would your reaction be?  I was asked just this question a number of years ago as I sat inside a Van der Graff generator with a few of my coworkers.  We all looked back and forth at each other in nervous silence for a minute before someone offered up a feeble sounding "sure."

The Museum of Science's Van der Graff Generator (Photo from the Museum of Science Boston)

I should probably explain how we all got to be sitting in the top of the generator in the first place.  One afternoon at lunch the man in charge of the lightening shows at the Museum of Science, I'll call him Len,  mentioned to us he was going to be cleaning out the insides of the generators and if any of us were curious what they looked like on the inside to meet him there tomorrow morning.  The next morning my boss and I along with some other curious coworkers gathered at the agreed on time in the lightening theater.  Len popped open the door at the bottom and instructed us to climb up the ladder to the ball at the top so we could see it innards.  One by one we climbed up the ladder next to a very long conveyer belt which had little brushes over it at the very top.  Once Len had joined us in the big ball at the top he proceeded to explain the generator worked like a big static electricity producer. The faster the conveyer belt ran the more static was produced by the brushes and the extra charge would build up on the outside of  the metal before discharging to create the lightening bolts we saw in his demonstrations.  After a few more minutes of questions from us Len then looks at us with a glint in his eye and asks "want me to hit you with a bolt of lightning?" After agreeing he slips back down the ladder and closes the door at the bottom.  We all let out a nervous giggle as the conveyer belt began to build up its static charge.  "Should this be open?" I shouted down to Len who now sat inside the Faraday cage at the controls.  "You're fine just keep your heads inside" he reassured us.

After a few tense minutes there was an audible crack and we all looked out the hole as the lightening hit the cage Len sat inside.  Cool we all thought as the belt began to spin faster now. After a few minutes of watching rather small lightening bolts hit the cage Len called up "Close the window." We did as instructed an sat completely enclosed in our metal sphere and waited.  Then there was another loud crack and a sound like someone throwing a tennis ball against the side of the metal.  On and on this went for a few minutes the belt spinning faster and faster, the cracks and bangs against the metal getting louder and louder.  When the banging reached deafening proportions we pounded on the sides of the metal sphere, our agreed on signal for Len to stop.  We waited for the belt to stop moving and the door at the bottom to be opened before descending back down the ladder.

"So?" Len asked after we had all safely made it out of the generator.  "Cool!" was our response. "How many volts was that last strike?" someone asked. "Enough to blow up a large redwood." Len casually responded.   

If your trying to figure out how we were all not blasted in to millions of little pieces the answer is simple and complex at the same time; we put our faith in the skin effect. Since I never took physics I can't really explain how this works, but because of the frequency of a bolt of lightening the charge was spread over the surface of the copper metal in which we sat and never penetrated the metal sphere. 

The same idea works if your sitting inside your car in a lightening storm as long as you DON'T touch anything inside the car, just sit there with your feet flat on the floor and hands in your lap. See this in action on BBC's Top Gear.

To see the Museum of Science's Van der Graff Generator in action check out this YouTube Video. https://www.youtube.com/watch?v=1-mFl_YXqiA  But it is MUCH cooler in person!

For More information:

For a great explanation on how the generator works and why Van der Graff created them in the first place see the HowStuffWorks website.
For a really in-depth explination of how the skin effect works. http://fermi.la.asu.edu/w9cf/skin/skin.html
More information on cars and lightening http://www.lightningsafety.com/nlsi_pls/vehicle_strike.html
How to be safe outside in a lightening storm. http://www.ready.gov/thunderstorms-lightning

For a brief glimpse inside the generator I sat in watch Since Bob's video. http://www.sciencebob.com/experiments/videos/video-van_de_graaff.php

What is it about chocolate?

Quick run to your kitchen throw open the cupboards and the refrigerator and look to see how many pieces of chocolate you find. Go on I'll wait.

So what did you find?  If your like me there is a lot of chocolate in your house or in my case there was until this last weekend when things when from good to poop in a rather short period of time. 

I was listening to the TED Radio hour on NPR over the weekend like I normally do and something caught my attention.....the mention of chocolate. This was kinda weird since the topic of the day was about success.  I perked up to hear Ron Gutman talk about smiling your way to success. "A smile, he reported, has the same brain stimulation as eating 2,000 bars of chocolate."  This was not the first time I had heard some scientific research related in terms of chocolate, but since I don't know who is reading this I will refrain from posting it because it is not appropriate for all age groups.

I started looking for fun sort of motivational facts about chocolate and here is what I came up with:

1)  "One chocolate chip can give a person enough energy to walk 150 feet.^"
                        (Bring on the chocolate chip cookies I say. )
2) "A Hershey's bar was dug up after 60 years from Admiral Richard Byrd’s cache at the South Pole.  Having been frozen all those years, it was still edible."
3) "Chocolate melting in a person’s mouth can cause a more intense and longer-lasting “buzz” than kissing."
                        (On the same note I read once that there are 22 calories in a Hersey Kiss and you burn 25 calories in a passionate one minute kiss. Not a bad way to burn calories if you ask me.)

4)   "Chocolate is a perfect food, as wholesome as it is delicious, a beneficent restorer of exhausted power. It is the best friend of those engaged in literary pursuits. – Baron Justus von Liebig (1803-1873), German chemist"
                         (I'm not sure exactly how these go together.)
5)  "Chocolate is a Vegetable: chocolate is derived from cocoa beans. Bean = vegetable. Sugar is derived from either sugar cane or sugar beets. Both are plants, which places them in the vegetable category. Thus, chocolate is a vegetable. To go one step further, chocolate candy bars also contain milk, which is dairy. So candy bars are a health food."
                          (It isn't but I like the logic here)

Why are we so enamored with chocolate is it the way it melts on the tongue, the fact that it gives us the same chemical happy feeling in our brains that other pleasurable things do, or is something coded in our DNA from way way back. Imaging being the Aztecs your trying to make something like beer and come up with chocolate were you bummed out by this or after some taste testing by your friends did you decide it was the best thing on earth?

Ruth Wakefield, who invented the  chocolate chip cookie, sold her recipe to Nestle for a lifetime supply of chocolate. You go girl! 

Whatever it is that has us so addicted may it never be factored out of chocolate.  I tip my hat to you Aztecs for your mistake is one of my favorite things.

Want more chocolate?
http://www.facts-about-chocolate.com/chocolate-quotes/
Even local bears love chocolate.  http://www.youtube.com/watch?v=_3GiXckb9z0
http://facts.randomhistory.com/chocolate-facts.html
http://www.webmd.com/food-recipes/rm-quiz-chocolate

It's Raining Antlers?

As I was returning home from a walk last week I saw a sight which just made me stand there and laugh. The one antlered elk. Try as the pour guy might he just could not make the other one fall off. Each year around the middle of March our antlered friends, the deer, elk, caribou, and moose loose their antlers. A hormonal change causes their antlers to fall to the ground. Sometimes they both fall off at once and other times.... Well let's just say there are some funny looking elk walking around. Why would you want to loose your antlers each year you ask? Simple to win over the girls. Imagine that during a particularly rough mating season you smashed heads with another make of your kind and broke off part of an antler. Now, since the females of your kind look for antlers which are the same on both sides you have just lost your chance at mating.  

                                            Copyright Peter Zuzga

 However, since antlers fall off each year as long as the animal has not damaged the part of the skull where the antler grows next year his rack will come back good as new.  Antlers unlike horns are made from bone and are shed each spring. Within a few weeks our antlered friends start to regrow their antlers and while they are in velvet antlers act as a built in cooling system for the animal. There is blood circulating underneath the velvet. It is hard to imagine an animal growing an antler of this size in just one season (April-early September), but they do.  Antlers are the fastest growing bone known to man and can grow as much as an inch a day at the height of the growing season.

                                                                   My Final Antler

Their weight is pretty impressive too. A full grown healthy male elk can have a rack which weighs a total of 40 pounds. That's a lot of weight to be carrying on your head all the time.

Since I am on the topic of antlers why don't I tell you about some of the differences between antlers and horns.

Antlers	Horns
Made out of bone	Made out of keratin (like your fingernails)
Are solid	Are hollow in the middle
On an elk they can weigh 40 pounds	On a Bighorn Sheep up to 30 pounds
Shed every year	With the animal for life

Just remember if you see a shed antler out in the woods it is best to leave it where it is there are many small rodents out there which eat the antlers to get much needed nutrients to help them grow. Think of shed antlers as vitamins for wildlife.  Happy antler spotting. 

Don't Do It! Don't Investigate The Wiggly Thing!

It lays curled on top of the snow, silent and motionless except for the end of it's tail. From across the snow alert eyes of a mouse see something small and back moving on the snow's surface. Could it be food? The mouse creeps in closer and closer until WHAM! Sharp canine teeth sink into it's neck snuffing out the mouse's life. Mouse in teeth the critter scurries back to it's den, inside is the fur and feathers of other unsuspecting creatures; ptarmigan, marmots, snowshoe hare, and weasels.

Who is this terrifying predator roaming the woods you wonder. None other than this guy, the ermine.

You were thinking some HUGE predator something like a coyote or fox weren't you. He maybe small but he shouldn't be overlooked or dismissed as some cute little furry creature. Ermines are one fierce predator taking on prey as large as a snowshoe hare or something as small as a mouse.       

These cunning carnivores often are seen hunting in a zig-zag pattern leaping over a foot in each jump, which is mighty impressive for a critter that is only 6-12 inches long. They use their keen sense of smell to locate their prey by investigating every hole, crevice, and cave in the rocks. In the winter if the snow is too deep they will tunnel into the subnivian layer, or under the snow to those non-scientists out there, and move around in tunnels looking for prey.  They will even flick their tail with it's small black tip in order to lure prey in closer, their white body perfectly camouflaged against the stark white snow.

In the spring these crafty little critters change color to be white on their belly and brown on top.  (Science moment: The increasing light levels in the spring trigger a hormonal change which causes their fur to gradually fall out leaving changing them from white to brown. The same thing happens in the fall. As the days shorten the hormonal change is triggered and the fur changes from brown to white.) Their high metabolism means they have to eat every day, so to make sure they always have a meal ready even when they can not catch one. They cache dead things in hole so there is always something to eat.

Look hard the next time your out in the snow and see if there are two small eyes starting back at you.

If you want to see some other cute ermine pictures check out Meg Sommers' web page she just captured some amazing photographs of an ermine in Yellowstone National Park. 

Cool Stuff You Never Knew About Snow!

Snow everybody's favorite four letter word has been falling a lot lately even in places where snow is a whole new concept. Well, I've been pondering snow, walking in snow, snowshoeing in snow, post-holing in snow up to my waist a bunch recently. So, here are three interesting facts I have learned about snow over the last few weeks as I prepared to teach an advanced snow science class.




1) It doesn't need to be warm to melt snow.
The temperature here in Colorado has been all over the map, 50 degrees one day 20 degrees the next with a lovely (said with a huge amount of sarcasm) wind. I was pondering the snow fluctuations recorded by our SNOTEL trying to get a handle on why if we get 241 inches of snow (that's a little over 20 feet) in an average year (October to June) why there never seems to be more than about 41-70 inches at any one time at the SNOTEL gauge?  The obvious answer is it melts. The only thing is while it can be 50 degrees at my house at the SNOTEL site, 3,000 feet above my house, the temperature ranged from 24-31 degrees Fahrenheit. So where the heck is all the snow going? Sublimation is the answer!  The constant 30-60 mile per hour winds are causing the snow to go straight from a solid into a gas without needing to melt first. A scientific paper I read showed the snow pack in the research location, not too far from where I work, decreased by 15% each year just due to sublimation.


2) Fresh power makes my eyes hurt!
Ever wonder why it seems brighter right after a light fluffy snow falls than a few days later?  Freshly fallen snow has the ability to reflect 90% of the solar rays which hit it's surface. After a few days when the snow has a chance to compact it looses some of its ability to reflect sunlight and only can reflect about 50% f the sunlight hitting it.


3) Best Insulation Ever!
There is naturally a small amount of heat radiating up from under the surface if the ground. Build yourself a snow cave and you can trap some of that radiating heat to help keep yourself warm.  Small animals, such as mice, have figured this out. While the surface of the snow maybe frozen solid the natural heat radiating from the ground causes the lower layers to melt slightly changing the shape of the ice crystals. This new crystal shape looks like sugar grains, hence the name sugar snow, this snow is much easier for small critters to move through than the hard wind packed snow on the surface. 

It's -17 Degrees and I'm Heading Outside!!!! Maybe?

The Polar Vortex has Wisconsin squarely in it's sights. Dog owners are breaking out the booties before letting the dog out to do their business and schools under the Vortex have closed for a cold day.  (For those of you reading this somewhere warm a cold day is where the temperature/wind chill is so cold that it is considered too dangerous to stand outside and wait for the bus.)

                                               Buck in his winter booties. By Peter Zuzga


In my years of living here, there and everywhere I've lived in some pretty cold places. Thankfully though I never owned a thermometer. I never needed a contraption to tell me how cold it was all I had to do was listen to the snow. The higher the pitch of the snow squeak the colder the temperature.  When you walk your weight squishes the snow causing it to melt slightly and "flow" out from under your boot, but when the temperature of the snow gets below 14 degrees Fahrenheit the snow doesn't melt as you step down on it. The squeaking is the sound the ice crystals make as they move against each other.  The louder the squeak the colder the temperature. While going to college in the Northeast Kingdom of Vermont (Johnson State College) my fiends and I had our own ideas of what cold was. If you made it across our small campus and your eyelashes were frozen together and the moisture from your nose had frozen your scarf fast to your face for most of your next class THAT WAS COLD! Squeaky snow not so cold.

Today it is cold and tonight is going to be even colder, oh the possibilities!! Nerds and science geeks across the vast world wide web have posted and blogged about ways to have fun in the cold. Maybe it all those years I spent teaching afterschool science experiment classes that is making me want to try all those experiments you can only do when it is REALLY COLD!  First on the list freezing a cup of boiling water instantly.   I'll let this really smart person explain.

 



 Next on the list frozen bubbles. You can also take one of those big bubble wands and just hold it out to watch the ice crystals form on the big loop.

Then there is my favorite cold weather experiment which you don't need it to be this cold outside to do. Blubber, blubber, blubber. This is really simple all you need is some blocks of lard (animal fat sold in grocery stores everywhere) and a few sealable bags. Take the lard and two sandwich sized bags and squish one block each into the bag. You want a lot of lard in each bag taking out as much of the air as possible. Then take another bag and place your two lard filled bags inside it. Stick one hand in-between the two lard filled bags in some ice water. The layers of lard will insulate your hand and keep it from feeling cold. This was a favorite of mine as a way to talk about insulation. I would then make kids insulate film canisters filled with liquid using natural insulation which animals collect to line their nests with.  Once they had insulated the canister we would place them in a snow drift and wait 25 minutes inside. The kids with the worst insulation would get and edible ice pop while those with the best insulation got chilled juice.

If you have fun trying any of these experiments, BUNDLE UP exposed skin can freeze in 30 minutes or less at these temperatures!!

More science experiments you can have fun with indoors where it is warm. Caution and a responsible adult needed.

http://kidscorner.org/html/science2.php
http://eo.ucar.edu/webweather/activities.html
http://www.sciencekids.co.nz/experiments.html

Donner and Blitzen Wears Night Vision Goggles!!!!

Soon Santa will he hitching up his reindeer to his sleigh to fly around the world dropping presents here and there. His stealthy reindeer will be sporting built in night visions goggles.  Most of us have heard about how Rudolph saved the day by using his shiny nose to light the way, but new research shows reindeer have built in night vision goggles which makes Rudolph's nose useless.

I've had people ask me what is the difference between reindeer and caribou, so reindeer are a domesticated animal and a caribou is a wild animal. Reindeer tend to be much small and are a slightly different color than their wild caribou cousins.


Caribou live in very extreme climates of Alaska, Scandinavia, and Russia where there is 19-20 hours of sunlight in the summer and 5-7 hours of daylight in the winter.  Caribou have an very cool adaption which helps them to deal with these light extremes.  They actually change the way the tapetum in the back of their eyes work. Click here for a cool picture of the color of their eyes in the different seasons. Like many animals which come out a night or are most active during the early morning and late evenings they have a tapetum, a reflective layer of cells in the back of their eyes, which allows their eye to collect the most amount of light making it easier for them to see.  Caribou take this one step further and through creating more or less pressure in their eyes, depending on the season, pack the tapetum cells closer together or spread them out. Spreading them out during the brighter summer season allows them to reflect more light back out through their eyes, but in the winter caribou increase the pressure in their eyes causing the tapetum cells to pack closer together. These closely packed cells allow caribou to catch more light making it much easier for them to see in the darkness. Adjustable night vision goggles!   

So have no fear whatever the reindeer the caribou will be able to see their way to your house to drop off those presents.

More fun stuff about caribou.
http://animals.nationalgeographic.com/animals/mammals/caribou/
http://www.livescience.com/17621-surprising-facts-reindeer-caribou.html
http://www.fws.gov/alaska/nwr/arctic/carcon.htm
http://www.mnh.si.edu/arctic/html/caribou_reindeer.html