Scientists think that Earth was formed over 4.5 billion years ago. This is the same as when the rest of the planets were formed. Earth is the fifth biggest planet in the whole solar system. It is also the densest planet. The Earth's axis of rotation is the diameter is roughly 8,000 miles. Earth is the third closest planet to the Sun. The average distance from the sun is approximately 93 million miles. The diameter of the Earth at the equator is 12,756 km which is 7,926 miles. The circumstance or distance around the Earth at the equator is 40,075 km. This is 24,901 miles. Earth is the only known planet to have big amounts of liquid water. Liquid water is mandatory to live. The size and composition are the physical characteristics of the Earth. Earth appears like a massive blue marble with swirls of white, brown, yellow, and green. 71% of the Earth consists of water which covers the Earth's surface. The white swirls in the Earth are all clouds. The areas of the Earth that are brown, yellow and green are the land and the areas of white are snow and ice. The equator is an imaginary circle that divides Earth into two halves. The Northern Hemisphere is the northern half of the Earth. The Southern Hemisphere is the Southern half of the Earth. The Earth's axis of rotation is consistently tilting beside its orbit around the sun. This causes the change of seasons which are Winter, Spring, Summer and Fall. During the summertime, the Earth is tilted so that the sun lands more directly. In the Winter the Sun appears lower on the horizon and the light comes at different angles. The summer days are longer than the nights because of the tilt of the Earth. The winter days are shorter and there is less sunlight. There is only one moon on the Earth. Earth's moon is the biggest moon of an inner planet. The Earth has a single moon. There are many characteristics and specifications of Earth's moon. The moon has a very small core. It is only 1 to 2% of the moon's mass and approximately 420 miles wide. It consists mainly of iron. Although it may also have big amounts of sulfur and other elements. The rocky mantle of Earth's moon is roughly 825 miles thick and is composed of dense rocks which are rich in magnesium and iron. The crust on top averages 42 miles deep. The exterior part of the crust is broken because of all the big impacts that has happened to it. The Earth consists of the solid and liquid portion and the atmosphere or gaseous portion for the composition.The moon on Earth is rocky. The atmosphere of the moon is likely very thin. Daytime temperatures on the sunny side of the moon can go up to 273 degrees F and it gets as cold as minus 243 F on the dark side. The specifications of the Earth's moon is that the diameter at Equator is 3.48 times 10^3 km (0.273 Earth's distance). The mass is 7.35 times 10^22 kg (0.0123 Earth m). The surface gravity is 0.17 times Earth gravity. The surface temperature is -170 degrees to 130 degrees Celsius. (-275 degrees to 265 degrees F). Earth appears flat although in reality the Earth has a small curve to it, which is why scientists confirm that the Earth is round. The mass of the Earth is 5.97*10^24 kg. The mass of the Earth is used to describe masses of rocky terrestrial planets. The size of the Earth is 3,959 miles (6,371 km). It is also the biggest of the terrestrial planets of the inner solar system. Earth is larger than Mars, Venus and Mercury. The gravitational relationship between the Earth and the Sun is geometrical. The Earth's orbital velocity vector and the Sun's velocity escape are at right angels to each other. Even though the Earth is moving away from the Sun at the same rate that the Sun and Earth enlarges into each other, the Earth happens to stay at the same distance. |