by Bill McLain
FACTOIDS
Some female fireflies do not have wings and look very much like flat larvae. These are called “glowworms.” Most glowworms give off a greenish light, but the “railroad worm” also has a red headlight.
Some frogs eat so many fireflies that they also glow.
The rhythmic flashes of the firefly are used to attract fireflies of the opposite sex.
Some fish give off definitive patterns of light to help them either form or maintain schools.
White phosphorus glows in the dark when exposed to air rather than light. However, the chemical reaction between it and the air can also cause it to explode into flames. It is extremely dangerous and has been used in warfare for years.
DID YOU KNOW?
If you live near an ocean or have ever taken a cruise at night, you may have seen the waves glowing with a blue-green tint or noticed that the wake of the ship was luminous.
This light is produced by large numbers of phosphorescent marine life such as plankton, jellyfish, and small crustaceans. They generate a heatless light by chemical means. The light produced is almost always blue-green. Some squids also surround themselves with a luminous light when in danger.
The deep-sea angler fish uses its light to great advantage. The lights in its mouth attract and illuminate prey which quickly fall victim to this predator.
Most of us have seen phosphorescent stickers, toys, and light sticks. But if you’ve ever seen the beauty of luminous ocean waves at night, you are indeed fortunate.
Why aren’t there 100 seconds in a minute and 100 minutes in an hour instead of 60? (Some people never did learn to use fractions.)
About 5,000 years ago there was a great city, Uruk, in Sumeria, an area we now call the Middle East. It was here that the earliest known writing was found, as well as a system of mathematics. This early numbering system was based on the number 60 rather than the number 10 as in our system. The ancient Sumerians divided each hour into 60 minutes and each minute into 60 seconds. Although their numbering system has not been used for centuries, their system of dividing hours into minutes and minutes into seconds survived and is still used today.
In our modern numbering system we use fractions to denote a part of something. For example, if we divide 10 by 3, our answer is 3?. However, if we want an answer without fractions, then we have only two choices because the number 10 can only be divided evenly by the numbers 2 and 5. (If we divide 10 by 1, we still get 10 so we don’t consider that combination here.) If we divide 10 by 2, the answer is 5 or “half,” and if we divide 10 by 5, the answer is 2 or “one fifth.”
The ancient Sumerians didn’t know how to write fractions, yet they often needed to know what a “half” or a “third” of something was. To solve this problem, an Uruk mathematician decided to base the Sumerian numbering system on the number 60, which can easily be divided by both halves and thirds. Although 10 can only be divided by 2 or 5 if a whole number answer is desired, 60 can be divided by 10 different numbers that provide answers without fractions (2, 3, 4, 5, 6, 10, 12, 15, 20, and 30).
FACTOIDS
Scientists have found chemical traces of wine proving that ancient Sumerians were drinking wine more than 7,000 years ago.
Sumerians were probably the earliest fish farmers. They kept fish in artificial ponds over 4,000 years ago.
A form of duplicating designs was invented by the Sumerians. They would inscribe a cylindrical stone with a design. This stone was then rolled over a soft clay tablet, leaving a reverse impression of the design. This principle of using a roller to duplicate a design is similar to the basic principle of a modern printing press.
The concept of multiplication was devised by the Sumerians.
Wagons were in use over 5,000 years ago. In Sumeria, the wagons had solid wheels. Copper nails were used to nail a leather tire to the wooden wheel. The wagons were pulled by oxen or by the Assyrian onager (wild ass), which is now nearly extinct.
The cuneiform writing of the Sumerians was not deciphered until the early nineteenth century.
What is the star closest to our sun? (Close but oh, so far.)
Generally speaking, the star closest to our sun is Alpha Centauri, which is 4.35 light-years away. However, it is actually a triple star system. Alpha Centauri A and Alpha Centauri B form a binary star, or two stars that orbit each other. Alpha Centauri A is larger than our sun while Alpha Centauri B is slightly smaller. The third star, Alpha Centauri C, is actually the nearest individual star to our sun and is 4.22 light-years away. It is significantly smaller than our sun, and because it is so faint, it was not discovered until 1915. Because of its closeness, it is often called Proxima Centauri.
Alpha Centauri intrigues scientists because it is one of the few stars in the galaxy that might offer life conditions similar to those in our solar system. To determine if a star possibly harbors planets that could support life, scientists have come up with five tests. Proxima Centauri fails all five, Alpha Centauri B passes most, but Alpha Centauri A passes all five.
The first test is that a star must fuse hydrogen into helium at the core, thereby generating heat and light.
The second test is that a star must be the right temperature. If it’s too hot, it may burn out too quickly and if it’s too cold it may not produce the energy needed to sustain life.
The third test is that the star must be stable. Instability would cause a star’s brightness to vary considerably, so that it would alternately freeze or burn any life on a nearby planet.
The fourth test is that a star must be old enough to give any surrounding planets time to evolve life.
The fifth and final test is that the star must have the chemical elements such as carbon, nitrogen, oxygen, and iron needed to produce planets and life.
FACTOIDS
Although 4.35 light-years seems like a small number, if you started a journey to Alpha Centauri as a baby and traveled at 10,000 mph, you would die of old age before you had completed less than 10 percent of the journey. Take heart, however, because after only 45,000 years of travel you would be halfway there.
The Hubble Space Telescope is currently checking for the existence of planets around Alpha Centauri.
The fastest-known star doesn’t have a name, just a number (PSR 2224+65), but it’s traveling through space at 1,000 miles per second (that’s well over 3.5 million miles per hour).
The asteroid that came closest to hitting the Earth was the size of a house and passed by on December 9, 1994, narrowly missing us by only 60,000 miles.
DID YOU KNOW?
Scientists and amateurs alike believe that there could be a planet orbiting Alpha Centauri. If Alpha Centauri is so much like our sun, wouldn’t its planet be similar to our earth? Not likely.
Although the planet’s terrain would probably be similar to earth’s continents, islands, and oceans, the planet would be different in most other ways.
Temperatures would be much higher than those on earth and could be lethal to humans trying to live in the tropical regions. Life would prefer the cooler highlands. The Arctic and Antarctic regions would probably be quite balmy, never reaching cold temperatures like earth.
The planet would be covered with clouds and the sky would be seen only rarely. The atmospheric pressure would be one and a half times that of earth’s. Although humans could tolerate it, they would probably move to higher elevations not only to live in atmospheric pressures similar to ours but also to escape the intense heat.
Because of the cloud cover and high temperatures, the weather would often be violent, spawning cloudbursts and hurricanes. The frequent rainfall would cause rapid erosion so there would be fewer high mountains. There would also be more rivers, lakes, and wetlands.
Although the planet would not be a Garden of Eden, humans could survive there. In fact, knowing how well people have adapted to extreme climatic conditions here on earth, humans would probably prosper.
A NASA expert stated that “we will discover extraterrestrial life in the ne
xt 25 years.” Perhaps it won’t be on Mars after all. It just could be a planet orbiting Alpha Centauri.
Why are the oceans salty but not lakes?
Most of the salt in the oceans comes from rocks containing various salts. Wind, rain, and erosion gradually wear down mountains and rocks. Rain then dissolves the salts into streams that eventually reach the sea. This has been going on for millions of years and that’s why the oceans are salty.
Although water vapor evaporates, rises from the ocean, and is carried to the land, the heavier salt is left behind. As the river waters from new rainstorms feed the oceans, they carry more salt. Thus, after every rainstorm the oceans become just a little bit saltier.
Most lakes are relatively new compared to the age of the earth, and the salt from rainwater has not had time to build up. In addition, many lakes have outlet streams or rivers to let the water out when it reaches a certain height. The lakes may also be in a cooler climate, which prevents a high degree of evaporation.
The famous salty lakes, such as the Great Salt Lake in Utah, the Salton Sea in Southern California, and the Dead Sea in the Middle East have no outlets. All are in desert climates and a lot of water is lost through evaporation. The new water coming in carries salt and these lakes build up salt deposits just as the oceans do.
FACTOIDS
Flecks of gold are suspended in seawater. If all of it were mined and distributed, every person on earth would get about 9 pounds of gold.
Although ocean water is warmer near the shore where it’s shallow, the average temperature of the deep ocean is just a little above freezing, around 39 degrees Fahrenheit.
The deepest-known spot in all of the oceans is the Mariana Trench in the Pacific Ocean, which is almost 7 miles deep.
Of all the water on earth, 97 percent is salt water, 2 percent is frozen water trapped in glaciers and ice caps, and the remaining 1 percent is fresh water.
Although we speak of different oceans, such as the Atlantic and Pacific, or of the Seven Seas, all oceans are connected and flow into one another.
The difference between low and high tides at the Bay of Fundy in Nova Scotia, Canada, can be as much as 50 feet, or the height of a 3-story building. They are the highest tides in the world.
The largest tidal wave ever measured was 210 feet, about 18 stories above sea level. It hit the coast of Siberia in 1737.
DID YOU KNOW?
Even fresh water contains salt but not enough to be noticeable. If you were to take a glass of fresh water and add a pinch of salt, it might still taste fresh or it might seem slightly salty, depending on your personal taste.
However, if you add a teaspoon of salt to a glass of water virtually everyone will complain it’s too salty to drink. That is almost the same proportion of water and salt as in the oceans. In fact, ocean water is about 220 times more salty than fresh water in a lake.
To give you an idea of how much salt this is, if all of the salt in the world’s oceans were removed and spread over all of the earth’s land, it would form a layer about as high as a 40-story office building.
However, this salt is not distributed evenly throughout the oceans. The Red Sea and Persian Gulf are very salty because evaporation is high. The Sargasso Sea in the North Atlantic is also very salty because the water temperature is high and it is too far from land to receive an influx of fresh water. On the other hand, some parts of the ocean are hardly salty at all. For example, water from the Columbia River in Oregon is so powerful that it travels over 200 miles from shore before mixing with seawater.
Is it true that opals contain a lot water? (More valuable than diamond?)
Opals usually contain 4 to 9 percent water, but some may contain up to 30 percent water. These precious stones are formed from lumps of silica and are actually silicon dioxide and water. The water in the stone cannot escape unless the opal is heated to extreme temperatures.
Most opal is more than 60 million years old and is typically found where hot springs once flowed. The silica in the springs lined the walls of cracks, vents, and cavities in the bedrock. When the hot springs dried up, the silica hardened into opal. It is one of the few gemstones that is sedimentary in origin.
An opal has an extraordinary ability to refract light and reflect specific wavelengths of light. This capability is so unique that the term “opalescence” was coined to describe it. Each tiny sphere of silica within an opal refracts a single pure spectral color depending on the size and spacing of the sphere. Looking at an opal can be like looking at water droplets in a rainbow.
When buying an opal you should consider the color of its “fire,” the intensity of its “sparkle,” and the rarity of the color. An opal is not subtle. Even in indirect light it shows flashes and flares of a mystical inner fire.
But most of all, you should choose one that simply appeals to you.
FACTOIDS
High-quality opals can bring as much as $80,000 per carat, making them more valuable than diamonds.
Arabs believed that opals have a fiery color because they fell from heaven in flashes of lightning.
Archeologists have found 6,000-year-old opal ornaments in African caves.
Opals were set in the crown of the Holy Roman Emperor and in the crown jewels of France.
The ancient Aztecs mined opals in Central and South America.
Opals are considered to be very magical. They are reputed to have healing powers and are used for various rituals. Black opals are the choice of witches. However, wearing a black opal near the heart is said to ward off evil and protect travelers.
Although opals are found in various parts of the world, 90 percent of the world’s gem-quality opals come from southern Australia. All black opals come from Australia.
It is said that Cleopatra wore an opal to attract the gaze of Mark Antony.
DID YOU KNOW?
Opals have a special meaning for the Aboriginal people living in Australia. They believe that they have lived in Australia since Dream-time, the beginning of all creation. Archeologists have proven that the Aborigines have lived in Australia for tens of thousands of years. To them an opal is something that a Dreaming ancestor left behind as a sign of the ancestor’s presence. One legend tells the story of how the people received the gift of fire from opals.
The people sent a pelican to explore the country so he could come back and tell them what was there. The pelican carried provisions of water and fish in his beak to sustain him on the long journey. But before he had flown very far, he became ill and landed on top of a hill. As the pelican rested, he saw that the ground before him was a kaleidoscope of color. He did not realize that he was looking at a field of opals.
Being curious, the pelican pecked at the flashing stones with his beak until he accidentally created a spark that lit the nearby dry grass. The flames grew larger and spread a great distance until they reached a group of people camping near a creek. The people took the fire and for the first time were able to cook their fish and meat. Their creator had given them the gift of fire.
More questions? Try these websites.
HOW THINGS WORK
http://landaul.phys.virginia.edu/Education/Teaching/HowThingsWork/home.html
This is the site of Louis A. Bloomfield, physics professor and author of the book How Things Work: The Physics of Everyday Life. Louis answers a myriad questions about physics such as “How do I explain Einstein’s theory of relativity to a seventh-grade student?” and “Why does cold water defrost things faster than hot water?”
SCIENCE ANSWERS
http://webfoot2.omsi.edu/online/whatzit/home.html#implode
Here you’ll find answers to questions about astronomy, chemistry, earth science, information science, life science, physics, and space science. All of the answers are written in easy-to-understand language.
ASK DOCTOR MATH
http://forum.swarthmore.edu/dr.math/frmath.college.html
Dr. Math answers questions about all branches of mathematics. When you go to this site, don�
��t be frightened when you see Answers: College Level and Beyond. Just click on All Levels to find answers at the elementary, middle, and high school levels. If you have a specific question, you can e-mail Dr. Math. Whenever I’ve written him, he’s always answered.
ANECDOTE: A VISIT FROM THE DUTCH ROYAL NAVY
I’ve always enjoyed helping people. If I can find an answer to someone’s question, then that’s a reward in itself. However, there are times when the reward is much more tangible … and totally unexpected.
Rob Dijxhoorn, who lives in the Netherlands, sent me an e-mail asking for some specific information relating to computers. I responded that same day and thought no more about it. Just another question, another answer, all in a day’s work.
I didn’t know until later that Rob was very excited when he received my response. He was thrilled not only because he had an answer that no one else had been able to give him, but also because the answer came all the way from California and had arrived the very next day.
Some months later Rob came to San Francisco on vacation and wanted to thank me personally. All he had was my e-mail address, which contained an acronym for the facility I worked in. He asked the hotel clerk what the acronym meant and the clerk told him. He then called directory assistance, asked for the phone number of the facility, called the receptionist, and asked for the street address. Rob then asked someone at the hotel for directions, rented a car, and drove the 50 miles from his hotel to the building where I worked.
