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.
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.
STEM through the lens
In 1953, a scientist named Edmund Schulman discovered that bristlecone pines are the world’s oldest trees. They live high in the mountains—between 9,000 and 11,000 feet above sea level where the soil is rocky, the air is as dry as a desert, and the temperatures are extremely hot in summer and cold in winter. Most ancient bristlecones grow in California’s White Mountains and Nevada’s Snake Range, and scientists now know that some of these trees are more than 5,000 years old. They are the oldest known living things on the planet.
Edmund Schulman used a boring bit, a tool shaped like a drinking straw, to drill into old trees and pull pencil shaped pieces of wood called cores out of the trunks of very old trees. Cores contain patterns of stripes. One stripe represents one year of growth. Schulman counted more than 4,600 stripes from a tree he named Methuselah--after the oldest man in the Bible.
Today, the Methuselah Tree’s exact location is kept secret to protect it from too many visitors. Like all ancient bristlecone pines, Methuselah’s annual growth rings contain secrets spanning thousands of years—secrets that are being discovered by scientists who know how to “read” tree rings. Rainfall, fires, volcanoes, droughts, and climate changes, are literally recorded in the growth rings.
In the summer of 2011, I went searching for Methuselah. I brought along my camera. Although I am not a tree-ring scientist, I did my own research using my five senses. I tasted the pitch and pollen from cones (it was a little bit bitter); smelled the bark (it smelled like rain); touched wind sculpted and sun bleached wood surfaces (it was smooth and grooved); listened to the sound created when I tapped the rock-hard wood (it was sharp and short); and I was amazed by their strange forms and colors (they looked like dancers).
Did I find Methuselah during my adventure? Actually, when I stopped searching,Methuselah found me. I will share that story along with a lot of science, in the book I am writing. But I won’t publish Methuselah’s photo or location. Some things must be kept secret.
Alexandra Siy says, "I write books that put the "A" into STEM! Reading about science should be as creative and fun as doing science. Science is not simply information and facts--it's about questions, exploration, and the process of discovery. My books are illustrated with real scientific images that bring alive the stories that inspire kids to think like scientists! " If you would like to know about some of her award-winning books, click here.
Alexandra 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 Oldest Tree on Earth." Nonfiction Minute, iNK Think Tank, 10 Oct. 2017, www.nonfictionminute.org/the-nonfiction-minute/the-oldest-trees-on-earth.