This unreflected solar radiation is turned into infrared radiation, or heat. Most of the energy reaches the troposphere as visible light, infrared radiation, and a small amount of ultraviolet radiation that wasn't absorbed by the stratosphere. About 34% of the solar energy reaching the troposphere is reflected back into space by clouds, dust, chemicals. Earth receives only about one-billionth of the sun's energy. This energy travels at the speed of light and reaches Earth in slightly more than 8 minutes. Tremendous pressure and temperatures in its inner core fuses the hydrogen nuclei and forms helium, releasing enormous amounts of energy. The sun is a huge ball of hydrogen (72%) and helium (28%) gases. Solar energy drives the climate and weather systems of our planet. Our sun is the source of energy for life. However, particles of the atmosphere are found 1,000 miles (1,600 km.) in space above the planet's surface. More than 99% of earth's atmosphere is less than 50 miles (80 km.) high. Ozone filters out most of the sun's harmful ultraviolet radiation. The stratosphere, or outer layer, stretches 11-30 miles above sea level and contains ozone (O3). It contains most of the planet's air, which consists of nitrogen (78%) and oxygen (21%). Its inner layer is called the troposphere and reaches only 11 miles above sea level. The atmosphere is a thin, gaseous layer of air that envelops the planet. Temperatures of - 128° F (-89° C) have been recorded at Vostok station in Antarctica. The highest temperatures on Earth have reached 136° F (58° C) at Al Asisiyah, Libya. Water covers approximately 139,500,000 square miles, or 71% of the total surface area. Approximately 57,300,000 square miles, or 29% of the total surface area is land. Earth's axis is tilted at a 23.5° angle.Įarth has a total surface area of 196,800,000 square miles. It makes one full revolution around the sun every 365 days, 6 hours, 9 minutes, and 9.45 seconds. The planet rotates once every 23 hours, 56 minutes, and 4.09 seconds. It is estimated to be over 4.5 billion years old. Only 11 percent of the incident sunlight is reflected back to the atmosphere from the water bodies.Earth is the third planet, and 93,000,000 miles (150,000,000 km.) from the sun. The sky is blue because the atmosphere scatters shorter wavelengths like the blue colour ore easily than the longer wavelength. Due to iron content in its soil, the mars surface is red in colour. This is because methane in gaseous form absorbs all the red wavelength from the sun and only reflects blue wavelengths. Methane is responsible for the blue colour of the planet. Neptune is another blue planet in our solar system whose atmosphere is made up of hydrogen, helium and methane. So, the answer to the question is option (A). This blue wavelength is responsible for the blue colour of the earth. When the sunlight which consists of all the wavelengths hits the water molecules in the seas and oceans, most of the wavelength which belongs to the infrared, red and ultraviolet range is absorbed by the molecules and what is left is the blue wavelength, which is reflected off the water surface. This is because the two-third of the earth consists of water bodies like oceans and seas. So, earth which consists of mostly oceans and seas, will appear blue in outer space.Įarth is known as the blue planet. The blue colour can be attributed to the water bodies present on the planet. Hint: The name can be derived from the colour of the planet as seen from outer space.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |