Friday, April 3, 2009

Planet Earth

Earth is the third planet, and 93,000,000 miles (150,000,000 km.) from the sun. It is estimated to be over 4.5 billion years old.
The planet rotates once every 23 hours, 56 minutes, and 4.09 seconds. It makes one full revolution around the sun every 365 days, 6 hours, 9 minutes, and 9.45 seconds. Earth's axis is tilted at a 23.5° angle.
Earth has a total surface area of 196,800,00 square miles. Approximately 57,300,00 square miles, or 29% of the total surface area is land. Water covers approximately 139,500,000 square miles, or 71% of the total surface area.
The highest temperatures on Earth have reached 136° F (58° C) at Al Asisiyah, Libya. Temperatures of - 128° F (-89° C) have been recorded at Vostok station in Antarctica.
The atmosphere is a thin, gaseous layer of air that envelops the planet. Its inner layer is called the troposphere and reaches only 11 miles above sea level. It contains most of the planet's air, which consists of nitrogen (78%) and oxygen (21%). The stratosphere, or outer layer, stretches 11-30 miles above sea level and contains ozone (O3). Ozone filters out most of the sun's harmful ultraviolet radiation.
More than 99% of earth's atmosphere is less than 50 miles (80 km.) high. However, particles of the atmosphere are found 1,000 miles (1,600 km.) in space above the planet's surface.

No comments:

Post a Comment