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end of the spectrum are the reds and oranges. These gradually shade into yellow, green, blue, indigo and violet. The colors have different wavelengths, frequencies, and energies. Violet has the shortest wavelength in the visible spectrum. That means it has the highest frequency and energy. Red has the longest wavelength, and lowest frequency and energy. LIGHT IN THE AIR Light travels through space in a straight line as long as nothing disturbs it. As light moves through the atmosphere, it continues to go straight until it bumps into a bit of dust or a gas molecule. Then what happens to the light depends on its wave length and the size of the thing it hits. Dust particles and water droplets are much larger than the wavelength of visible light. When light hits these large particles, it gets reflected, or bounced off, in different directions. The different colors of light are all reflected by the particle in the same way. The reflected light appears white because it still contains all of the same colors. Gas molecules are smaller than the wavelength of visible light. If light bumps into them, it acts differently. When light hits a gas molecule, some of it may get absorbed. After awhile, the molecule radiates (releases, or gives off) the light in a different direction. The color that is radiated is the same color that was absorbed. The different colors of light are affected differently. All of the co

d after Lord John Rayleigh, an English physicist, who first described it in the 1870's.) WHY IS THE SKY BLUE? The blue color of the sky is due to Rayleigh scattering. As light moves through the atmosphere, most of the longer wavelengths pass straight through. Little of the red, orange and yellow light is affected by t

As you look closer to the horizon, the sky appears much paler in color. To reach you, the scattered blue light must pass through more air. Some of it gets scattered away again in other directions. Less blue light reaches your eyes. The color of the sky near the horizon appears paler or white.

ORIGIN OF THE CELEBRATION Section: Festival The start of the New Year has been celebrated in China for more than 3,000 years. New Year was a time when the farmers gave thanks for the harvest and prayed to the gods for a good harvest in the coming year. This was the one period in the busy farming year when there was time to have a celebration and when the family could get together, relax, and be merry. Chinese New Year begins with a New Moon. The Lunar Year is calculated from the time it takes for the Moon to travel around the Earth, while the Western (Gregorian) calendar is based on the time it takes for the Earth to circle the Sun. The orbits of the Moon bear no relation to the time it takes for the Earth to go around the Sun, which is why the Chinese Lunar New Year is celebrated on a different date each year. In China the New Year was renamed the Spring Festival, in 1911, when the Western calendar was officially accepted in China. However, it is still commonly known around the world as the Chinese New Year. Chinese years are named after one of twelve animals. These have been used in the same order to name the years since the sixth century A.D. Each animal is said to have its own personality and emotions, which are present in people born within its year. ~~~~~~~~By Sarah Moyse This article is copyrighted. All rights reserved.Source: Chinese New Year (0-7613-0374-X)

RELIGIONS AND RITUALS Section: Festival Although the New Year celebration is not mainly a religious one, many Chinese will visit a temple at this time of the year to make an offering to the Buddha or to the gods in the hope of making the New Year a good one. Ancestors and gods are honored with ceremonies in the home around a family altar decorated with flowers. Incense and candles are burned at the altar. At important family banquets the ancestors may be recognized as "spiritual guests" and first offered food that is afterward eaten with the meal. The Chinese have three main systems of ideas that are important to them: Confucianism, Daoism, and Buddhism. Although these systems are very different, many Chinese follow some or all of the rituals associated with them just to be safe. Confucius lived in the fifth century B.C. and spoke about the value of good behavior in private life and in government. He said that politeness, honesty, courage, and loyalty were what made good people. He believed in self-development through education and thought that people gain in wisdom as they grow older. It is part of the Confucian tradition to honor parents and ancestors.

Daoism comes from the teachings of Laozi, who lived at the same time as Confucius. His book, the Dao De Jing (The Way and Its Power), describes the way (dao means "way") to live at peace with nature so as not to upset natural balances. The Way involves balance between opposite forces. They are called yin and yang. While yin is dark and female, yang is the opposite, being light and male. When yin and yang are balanced, there is perfect harmony with nature. Unlike Confucianism and Daoism, which started in China, Buddhism came from India and is based on the teachings of the Buddha -- a holy man. Buddha taught that people need to let go of earthly desires and become fully aware of what they are doing in the present. Buddhists believe that after death each soul moves on to another body, which may be animal or human. What one is chosen for in the next life depends on how good or bad the person has been in this life. The Chinese also pray to other gods, holding the view that the more gods who can look after them the better. The important ones are the Kitchen God, who watches the family in the home, the Jade Emperor, who is the most important god in heaven, the God of Wealth, who determines how wealthy people are, and the Door Gods. ~~~~~~~~By Sarah Moyse This article is copyrighted. All rights reserved.Source: Chinese New Year (0-7613-0374-X)

Solar energy can also be used to make electricity.

solar power plants, like the one in the picture to the right in California's Mojave Desert, use a highly curved mirror called a parabolic trough to focus the sunlight on a pipe running down a central point above the curve of the mirror.

mirror focuses the sunlight to strike the pipe

The western portion of Prince William Sound was the most heavily oiled in 1989 and oil on some beaches remains a serious concern for residents of the Sound who use these areas.

The remaining 1,100 miles of oiled shoreline were considered to have light to very light oiling. Crews visiting beaches in 1993 found hundreds of sites that contained substantial oil deposits.

A 1992 National Oceanic and Atmospheric Administration (NOAA) study* estimated that a great majority of the oil evaporated, dispersed into the water column or degraded naturally.

One unique feature of bats is their modified forelimbs, which support a wing membrane (patagium). The basic elements of the mammalian limb are present in bats, although the relative sizes of most bones and muscles differ from those of nonflying mammals. The most elongated parts of the limb are those of the hand (metacarpal bones) and fingers (phalanges). The primary functions of these bones in bats is to provide support for the patagium and control its movements.

Numerous blood vessels and nerves are present throughout the wing membrane. Bats also have five unique muscles present in the patagium, and use additional muscles in the chest and back to move the wings up and down.

The most obvious difference between bird wings and those of bats is that bird wings are made of feathers, not a skin membrane. Birds have an elongated arm, but do not have elongated fingers like bats. Additionally, the muscles used in both the upstroke and downstroke are found in the chest of birds, while the upstroke muscles are on the back in bats (Fenton, 1983).

According to the American College Dictionary, pollution is defined as:  �to make foul or unclean; dirty.

When it is unfit for its intended use, water is considered polluted.

Point sources of pollution occur when harmful substances are emitted directly into a body of water.

They give the order Chiroptera its name (literally, "hand-wing"), and functional wings and true flight are characteristics of all bats.

The wing membrane is an extension of the skin of the body. It is made up of external epidermis and an internal layer of dermis, which contains blood vessels (easily seen in a live bat when the wing is stretched in front of a light) and muscles.

Dog lovers have no problem telling you why the dog is considered man's best friend

Loyalty, unconditional love, companionship and laughs

Canine Assistants

Dogs have been used as guards, hunters, draught animals, eyes for the blind, drug and explosive detectors, rodent controllers- and even weapons! In Roman times and the Middle Ages, mastiffs wearing light armour, carrying spikes and pots of flaming sulphur and resin ran into battle against mounted knights. In World War II the Russians trained dogs to run suicide missions between the tracks of German tanks with mines strapped on their backs.

He conceived the basic idea of an electromagnetic telegraph in 1832, and produced the first working telegraph set in 1836. This made transmission possible over any distance.

can easily converse at 20 to 30 words per minute

Morse Code can be transmitted using sound or light

Scientists made an alarming discovery in the 1980s: The average surface temperature on Earth is slowly increasing. This trend is known as global warming. It is believed to be caused by an increase in the amounts of certain gases in the atmosphere. Greenhouse Effect To understand global warming, it helps to first understand something called the greenhouse effect. A greenhouse is a glass house in which plants grow. The glass lets light in and at the same time keeps heat from getting out. This trapped heat keeps the plants warm even when it is cold outside. Likewise, Earth's atmosphere traps energy from the sun. Carbon dioxide and other gases—called greenhouse gases—in the air do this trapping. Without these gases too much heat would go back into space, and living things could not survive. However, as more greenhouse gases get into the air, they also trap more heat. This leads to global warming.

Bats are not flying mice; they are not even remotely related to rodents. Bats are such unique animals that scientists have placed them in a group all their own, called 'Chiroptera’, which means hand-wing. Bats are grouped with primates and lemurs in a grand order called Archonta.

Bats are not blind. Most bats can see as well as humans. Fruit bats have eyesight that is adapted to low-light, much like cats. Fruit bats also see in color.

If a bat swoops toward you, it’s probably after the mosquito that is hovering just above your head -  not your hair.

Today we enjoy skydiving as a breathtaking leisure sport, but its origins lie within the army.  The history books are chock full of dates and occurrences where skydiving has played an important part.

Army skydiving had a big role to play in the Second World War, when paratroopers dropped into enemy zones to fight