The “Julia Child” of kids’ hands-on science
How do you know it’s the holiday season? There are lights everywhere sending that message. But that’s not the only kind of message light can send. A little more than 100 years ago when a telegraph began to become popular, people sent wireless messages called heliographs. They were made of flashes of light in Morse code (the same pattern of short and long as used in telegraphs) by reflecting the sun’s rays with a mirror. When the mirror was at a particular angle to the sun, it reflected a flash of bright light to observer miles away.
Maybe there’s another way to send light. Put a holiday light on one rim of a heavy glass measuring cup or dish. See where the light emerges on the rim on the opposite side. Move the light back and forth and watch what happens on the other side. The light travels down the side, and bends to go across the bottom and up the other side, but if you look at the cup sideways you can’t see the beam. Light stays inside the glass as it travels from rim to rim.
Could we make something like a wire from glass that can transmit light? Absolutely! An optical fiber is a flexible, transparent fiber made of glass or plastic that acts as a wire for light. Imagine a beam of light entering a fiber at exactly the right angle to bounce off the inside wall of the fiber where it meets the air. It is then reflected at exactly the same angle to bounce off the opposite wall making a zig-zag path until it reaches the end of the fiber. This internally reflected light stays inside the glass fiber as it travels at the speed of light.
HUGE quantities of all kinds of information—words, pictures, music, and videos—can now be sent through optical fibers, much more than through wires. A modern network with copper wiring can handle about 3,000 telephone calls at the same time, while a similar system using fiber optics can carry more than 30,000!
So when you hit “send,” know that your holiday message is a blinking beam of light, bouncing off the inside walls of a glass fiber on its speedy journey to friends and family. How ‘bout that!
Want to know more about optics? Have a look at Vicki Cobb's book Light Action! She co-authored it with her son, Josh, who is an optical engineer and her other son, Theo, drew the pictures. It's full of experiments that let you use optics to:
-Bend light around corners
- Stop time with a pair of sunglasses
- Capture light on a silver tray
- Magnify pictures with an ice cube
- Pour light into your palm
- Project a big-screen image from your small TV
- Fool a doorbell with a bike reflector!
For more information, go here.
Vicki is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.
MLA 8 Citation
Cobb, Vicki. "What Can You Learn from a Holiday Light and a Glass Cup?" Nonfiction Minute, iNK Think Tank, 14 Dec. 2017, www.nonfictionminute.org/ What-Can-You-Learn-from-a-Holiday-Light-and-a-Glass-Cup.
Nonfiction is the new black
When the Seleucid emperor Antiochus IV came to power in 175 BCE after his brother was assassinated, he insisted on being called Antiochus Epiphanes (“Antiochus the Visible God”). To the Jews who had the misfortune to be among his subjects, he was Antiochus Epimanes (“Antiochus the lunatic”).
No matter his name, he was definitely bad news to the Jews. Because of his Greek background, Antiochus believed in many gods. The Jews, on the other hand, were monotheistic. Antiochus soon began imposing his beliefs on the Jews and making it much more difficult for them to practice their religion. For example, anyone caught circumcising their newborn children would be put to death.
In 168 he sacked Jerusalem. His forces cut down thousands of defenseless Jews of all ages, looted and desecrated the Second Temple, and erected a massive statue of the chief Greek god Zeus (using himself as a model for the sculptor who created the statue). Soon the altar ran red with the blood of swine that were slaughtered as sacrifices. For good measure, Antiochus also outlawed the Hebrew religion.
The outraged Jews fought back. An elderly priest named Mattathias and some of his men killed a group of Seleucid soldiers. That ignited a revolt against Antiochus’s rule. When Mattathias died, his son Judah assumed the leadership role. Judah soon acquired the surname of Maccabee (“the hammer”) for his skill in battle. After a series of successful guerrilla operations, he led his vastly outnumbered forces to two decisive victories that resulted in the recapture of Jerusalem in 165.
The first order of business was cleansing the temple so it could be rededicated. The ceremony began on the 25th day of the Hebrew month of Kislev. According to legend, the small amount of purified oil that was readily available for the rites was expected to burn just a single night. Instead it burned for eight nights, when a new supply became available. That miracle gave rise to the ceremony of lighting one candle for each of the eight nights of Hanukkah, which means “dedication.”
Because the Hebrew calendar is lunar-based, the dates of Hanukkah change each year. This year Hanukkah begins [December 12] at sunset and lasts until sunset on December .
To the Jewish families who celebrate the holiday, Happy Hanukkah!
The holidays are approaching and millions of people will be listening to Handel’s Messiah. Read all about the composer in Jim Whiting’s Masters of Music biography.
MLA 8 Citation
Whiting, Jim. "The Story of Hanukkah." Nonfiction Minute, iNK Think Tank, 11 Dec. 2017, www.nonfictionminute.org/the-story-of-hanukkah.
Science through the lens
Which lunch food has a shape that resembles a falling raindrop?
b. potato chip
c. hot dog
d. hamburger bun
e. all of the above
f. none of the above
If you chose (f), you’re like most people who think raindrops are shaped like tears.
If you chose (e), you’re probably just hungry.
In either case you’re wrong.
That leaves us with lunch. Let’s start from the top.
Choice (a), orange, is a sphere. Water droplets are spherical because water is cohesive, meaning it sticks to itself. The “skin” that holds the drop together is surface tension and the reason insects can walk on water.
If you chose (a), you made a logical choice based on the properties of water, but you are wrong. Notice that you were not asked to identify the shape of a raindrop sitting on a leaf. You were asked to identify the shape of a falling raindrop. (Always read questions carefully!)
Moving down the list to (b), we encounter the potato chip. Potato chips come in many shapes, ranging from relatively flat to completely crumpled. Have you ever seen a raindrop that looks even a little bit like a potato chip? If you chose (b) you are wrong, but have a good sense of humor.
Choice (c), hot dog, is an interesting option. Could a spherical drop of water morph into the cylindrical shape of a hot dog? After all, a hot dog is a cylinder with a hemisphere (half sphere) on each end. Could a water droplet in free fall separate itself into two hemispheres with a long drip of water in between? Although this is an imaginative idea, the laws of physics make it impossible.
Choice (d), hamburger bun, is the only remaining choice, and is the correct answer. Here’s why:
A raindrop is acted upon by three forces: gravity, buoyancy, and drag. Gravity is the force that pulls the drop toward the earth, while buoyancy of the surrounding air pushes it upward and keeps it from falling. When the force of gravity is greater than the force of buoyancy, the raindrop falls. The air around it creates drag, slowing the drop down to its maximum speed. In the process, the sphere is distorted into a shape that resembles a hamburger bun.
Got it? Now, you may go to lunch.
Bugs bite, drink blood, and rob food from gardens and fields. They can even kill plants, animals, and, occasionally, people. Is bugging a crime? In her latest book, Bug Shots, Alexandra Siy compiles "rap sheets" on several of the major categories of bugs and takes a very close look at some of the types of insects in an engaging text. For more information, click here.
Alex Siy is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.
MLA 8 Citation
Siy, Alexandra. "The Race for the Sky." Nonfiction Minute, iNK Think Tank, 7 Dec. 2017, www.nonfictionminute.org/ A-Raindrop-Quiz.
Daddy longlegs are the spiders we run across the most often, right? Think again.
How many body parts does a spider have? Two. A “head” (called a cephalothorax) and an abdomen (where that sticky silk comes from). How many body parts does a daddy longlegs have? One. So, these animals aren’t even spiders. Daddy longlegs are one of many animals called opilionids (oo-pill-ee-OH-nidz). They are in the same animal class as spiders (Arachnida), and they all have long legs so they look like spiders—but they’re a separate order.
Opilionids aren’t dangerous to humans, but their predators had better watch out. Scientist Dr. Thomas Eisner discovered that a daddy longlegs carries toxin in its armpits. His research began one day when travelling through Texas. He picked up a daddy longlegs and smelled it— that’s right, his nose was his scientific instrument. He observed an odd smell so he carted the creature back to his motel room and studied it. The smell was a toxic chemical called benzoquinone (say BEN-zo-qwi-NO-ne). So of course, Dr. Eisner wanted to know more about that!
The chemical is toxic when it is a gas or a liquid, but not when it is a solid. On the side of the animal’s body–basically in its armpit–Dr. Eisner found a sac-like gland. In that gland? Solid benzoquinone.
When a predator such as an ant threatens the daddy longlegs, he spits up a drop of gut juice. That liquid travels down a groove from his mouth to the gland. In less than a second, he dissolves a bit of that benzoquinone into the liquid and creates toxic ammunition. You know those two long legs daddy longlegs use as feelers? He dips the tip of one of them into the toxic drop then slaps it on his predator.
Take that you scary ant! They flee.
The opilionid can reload his feelers up to thirty times from one toxic drop. When his ammo runs low, all he needs to do is drink water and spit again. Other types of opilionids skip the feelers and just let the liquid ooze out around their body, creating a super toxic safety shield.
What other secrets might opilionids be hiding? Not many people study them, so who knows?!? Maybe you will sniff out a discovery!
Some bugs litter. Some pass gas. Some bugs throw their poop! Discover ten of the rudest, crudest bugs around. Full of scientific facts, humor and just the right amount of yuck, Heather L. Montgomery's How Rude! features a countdown of the top 10 bad bugs who just won't mind their manners. One part illustration and one part photography, How Rude! is hilarious, informative, and seriously gross!
MLA 8 Citation
Montgomery, Heather L. "Toxic Armpits." Nonfiction Minute, iNK Think Tank, 6 Dec. 2017, www.nonfictionminute.org/ Toxic-Armpits.
STEM through the lens
Chances are you’ve seen this photograph before—maybe on a T-shirt, on a billboard, or in a TV ad. The “Blue Marble Shot” has been reprinted more than any other photograph in history. It was taken on December 7, 1972, by one of the three Apollo 17 astronauts on their way to the Moon. But no one knows which astronaut took the picture because all three claimed to have been the photographer.
During the few minutes Apollo 17 flew across the place in space located directly between the Sun and Earth (which was 28,000 miles away), no one should have been looking out of the window as they all had important tasks to do. But, obviously, someone, and perhaps everyone, was looking out. One of them grabbed a camera and clicked the shutter four times.
After Apollo 17 returned to Earth, the picture was published on the front page of newspapers all over the world. For the first time ever, people saw the full planet Earth completely flooded in sunshine. Heavy clouds swirled over vast oceans. The African coastline was clearly visible, with its northeastern edge fitting like a puzzle piece with the Arabian Peninsula. Madagascar, the fourth largest island on Earth, was slightly off center, looking like a slipper floating in the middle of the Indian Ocean. And because the photo was taken just two weeks before the winter solstice, Earth’s southern hemisphere was tilted toward the sun, revealing Antarctica. For the first time ever, the south polar ice caps appeared in a photo.
The mystery of who took the picture has never been solved. The commander of the mission, Eugene Cernan, who was the last man to walk on the moon, says he snapped the picture. But would the commander have had the time to take the photo at that critical point of the flight? Harrison “Jack” Schmitt, the first geologist sent to the moon, also swears that he took the picture. Perhaps that makes sense because he was responsible for making scientific observations. Ron Evans, who died in 1990, also claimed that he took the picture.
No one will ever know for sure who took the Blue Marble Shot. But the words of Commander Eugene Cernan describe what he saw out of his spaceship window “…you can look out the window and you're looking at the most beautiful star in the heavens— the most beautiful because it's the one we understand and we know, it's home, it's people, family, love, life —and besides that, it is beautiful. ”
In Alex's book Cars on Mars you can follow the course of NASA’s Mars Exploration Rover (MER) mission as twin rovers Spirit and Opportunity explore the Red Planet. Learn how scientists determined that there was once water on Mars and how the earthbound NASA team resolved problems with the rovers from afar in order to prolong the mission, which continues today. For more information, click here.
Alex is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.
MLA 8 CItation
Siy, Alexandra. "Mystery of the Blue Marble." Nonfiction Minute, iNK Think Tank, 30 Nov. 2017, www.nonfictionminute.org/ Mystery-of-the-Blue-Marble.