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North and South Pole areas for most people are real secret. Most people have a vague idea on these areas and imagine them as areas very similar to each other. It is strange that between the Antarctic areas (South Pole) and Arctic areas (areas of the North Pole) there are more differences than similarities! The area of the South Pole is mainly composed of the continent called Antarctica. This continent covered with snow and ice, has an area larger than Europe. In contrast, the North Pole area consists of the Arctic Ocean, surrounded by the shores of North America, Europe and Asia. Other big difference is that the man, animals and plants gradually migrated northward in the North Pole area, adapting to the polar environment, but on the area of the South Pole, which is separated with hundreds of kilometers of ocean from all continents except South America, there are no land animals or people. Plant life is there so poor that there only grow lichens, algae, grasses and some other plants. P...

Why do Seasons Change - What Causes the Change in Seasons? People since ancient times considered the change of seasons. Why is it hot in summer and cold in winter? Why the days get longer in the spring? Why during the winter the nights are longer? We all know that the Earth revolves around the sun, and at the same time around its axis. If the Earth's axis (the imaginary line that passes through the North and South Pole) was at 90 degrees to the Earth's orbit around the sun, than we would have no distinct seasons, and all the days of the year would have the same length. But the Earth's axis is slightly tilted and this is because on the Earth influence various forces. One is the attraction toward the sun, the other is attraction of the moon, and the third is the Earth’s movement around its axis. Due to the action of these forces, the Earth revolves around the sun in an inclined position. The Earth is always throughout the year in this position, so that the Earth...

The Equator is very well marked on each map or globe, so for some people it is hard to believe that it doesn’t exist. The Equator is only one imaginary line, which we can always cross and not to know that we’ve crossed it. That’s why the sailors celebrate every passing of the Equator with appropriate crossing ceremonies. What is the Equator? The Equator separates the Earth to northern and southern hemispheres. It is an imaginary line that goes around the circle the Earth in the middle, between the North and South Pole. Other imaginary lines that make a circle around the Earth parallel to the Equator are called "parallels". The Equator is marked with zero, and the lines above and below it, signify north and south latitude, which are used to make it easier to locate a point on the Earth's surface. As we know the Earth in the maps is divided into several areas. Starting from the top, or from the north, we have the arctic regions, tropical regions and the south tempe...

Moving continents - Are the continents still moving? If you look at a map of the world and the shapes of Africa and South America, you will notice that they seem to fit together. If you make a jigsaw puzzle of the two shapes, you will see that this is true. Early in the 20th century, a German scientist called Alfred Wegener studied fossils in rocks from Africa and South America. Fossils are imprints or remains of plants or animals usually found in rocks. He found that the fossils on both continents were the remains of the same animals and plants. He introduced the theory that mountains in different countries might once have been joined together. The Cape Mountains in South Africa, for example, could have once been joined to mountains south of Buenos Aires, in Argentina. Wegener believed that, over millions of years, the continents had gradually moved away from each other. Continents are still moving today. Scientists call this movement the continental drift. Why are the co...

Why the earth is round in shape? Why does the earth spin? Why does the earth rotate around the sun? The answers to these questions are connected to the story of “How was the Earth Formed”. It all started billions of years ago, with a giant, spinning cloud in space. There are many such clouds in space right now. They are made up of chemicals in the form of gas and dust. Some of these clouds are turning into new stars, the same way as five billion years ago, our sun and its planets were formed. These clouds are hundreds of millions of miles wide! The force of gravitation (the same force is keeping us on the ground) pulled the gas and dust particles into a shape of a huge, flat wheel, which spins around. Gravitation slowly pulls the cloud together. Most of the gas is collected in the middle of the cloud and forms a lump that grows bigger and bigger. As the lump gets bigger, its gravity becomes stronger and it pulls more gas into itself. Because gravity pulls equally from all direct...

How does a light bulb work - for kids? Have you ever looked closely at an ordinary electric light bulb? Hold it carefully while you do so. Inside, you may see wire "legs" holding up a thinner wire arranged in a coil. When a light bulb is switched on, electricity flows along the thin wire and makes it glow. Why does it glow white, and not red like the wire in an electric heater? Why doesn't the thin wire quickly burn out? Many bulbs are filled mostly with argon gas. Because argon is inert, or chemically inactive, it allows the wire to glow brightly without burning. If the bulbs were filled with air or oxygen, the wire would be destroyed by burning. The wire glows white because it is so hot—over 4500°F (2482°C). And it doesn't melt because it's made of a metal called tungsten, which melts only at extremely high temperatures. Gases in bulbs Sometimes the gas inside a lamp produces a colored light. Different gases glow in different colors. Street li...

How is natural gas produced?- natural gas for kids The most important gas that we use as a source of energy is natural gas. We don't have to make this. It is found in deposits under the ground, usually near deposits of oil. Natural gas is a mixture of several gases, including butane and propane. Most of it is methane. Natural gas comes from vegetation that decomposed millions of years ago. Natural gas is used to provide heat for industry, and also for cooking and heating in our homes. It comes to our homes through pipes laid under the streets of towns and cities and across the countryside. In some places, natural gas is piped direct from the gas production platforms, where it has been pumped up from beneath the seabed or from deep underground. In other places, it is shipped as a liquid in refrigerated tankers. It is pumped from the ships into storage tanks at the docks. Adding a smell Unlike gas made in gasworks, natural gas doesn't have an odor. This means that w...

Traveling to Antarctica - Information about Antarctica Antarctica is located around the South Pole. The Antarctic continent is the fifth largest among the continents, with an area similar to the areas of the United States and Europe together.   Antarctica is the coldest part of the globe. Antarctica is surrounded by the most turbulent seas in the world. There are blowing cold winds, frequent storms, little water sediment, and winter are so strong that the whole of this area is almost completely deserted. There is never enough solar heat in the country, which during the whole year is covered in snow. The lowest temperature that was ever recorded in the world, was found just in Antarctica. Due to the immense cold, in Antarctica the food doesn’t spoil, there are no mold, mildew, or bacteria. What lies beneath the ice cover? It is not known exactly, because the Antarctic is not yet sufficiently researched. The researchers noted coal deposits and some minerals. It is possible the...

Pollination definition for kids Have you ever noticed how pleasant many flowers smell? They have attractive scents, as well as bright colors, in order to attract insects. Insects use the nectar made by flowers as food. In the process of getting food, the insects transfer pollen from flower to flower. The process of seed formation begins with this transfer of pollen grains from one flower to the stigma of another flower of the same kind. This transfer is called pollination. The main insects which pollinate flowers are bees and butterflies. These insects feed on the sweet, sugar liquid called nectar that is usually produced by special cells in the receptacle. On its way to the nectar, the insect has to pass the flower's anthers, which are covered in pollen. Some of the pollen sticks to the insect's body and then brushes off onto the stigma of the next flower that the insect visits. A thin tube grows from the pollen grain, down through the style, and into the ovule. A male cell,...

Germination of seeds for kids - What is germination? Have you ever tried to grow your own plants? If you have, you may have started with seeds. Plants have male and female parts. In seed-bearing plants, the male reproductive cells, called sperm, are carried in tiny grains called pollen. These cells are released into the ovary, the female part of the plant. There, one of the sperm joins with a female reproductive cell, called an egg, to start a new plant. This tiny new plant, called an embryo, is at first kept in a seed with its own store of food. Seeds can be many different shapes and sizes but they all do the same job. They are scattered away from the parent plant. The outer cover of each seed protects the embryo until the seed lands in a suitable place. When conditions are right, the seed takes up water and the new plant grows out of it. This is called germination. What do seeds need to germinate? How do seeds germinate? The name for the moment in which seeds sta...

Metatarsalgia definition - What is Metatarsalgia? Metatarsalgia is defined as pain in the instep area. What causes Metatarsalgia? The most common Cause is a form of flatfoot in which the arch between the bases of the big and little toes is deformed and the heads of the metatarsal bones rest on the ground. This pressure on the bones produces pain, causes the skin to thicken, and may eventually cause the toes to curl. Metatarsalgla may also be caused by a stress fracture, which can occur after prolonged walking or running. Metatarsalgia treatment Rest of the injured foot and wearing a soft-soled shoe is usually the only treatment required. Prolonged physiotherapy to strengthen the underlying muscles may be effective in patients under the age of 40 years. But if the pain is severe, it may be necessary to wear a cast for about one month.

Mercury chemical element - facts about mercury element Mercury is a liquid, metallic element that is commonly used in thermometers and other measuring instruments. Some mercury compounds are still used in antiseptics and eye ointments. What is the chemical symbol for the element mercury? The chemical symbol for the element mercury is: Hg Atomic Number: 80 Atomic Mass: 200.59 amu Number of Protons/Electrons: 80 Number of Neutrons: 121 Who discovered the element mercury? The element mercury was known since ancient times and it is unknown who discovered it first. Its name originates from the planet Mercury Is mercury poisonous? Small amounts of liquid mercury, such as that found in a thermometer, are not especially dangerous, because the element if ingested is poorly absorbed by the gastrointestinal tract. However, mercury compounds, known as mercury salts, and mercury vapor are toxic, particularly the vapor, which is very readily absorbed through the lungs. It affects the br...