Planet Earth is third from the sun and it is known to support the life of living things. According to radiometric evidence, the planet was formed about 4.5 billion years ago. It is the densest planet of the solar system and the largest of the rocky planets. Earth has a gravity that is linked to other space objects including sun and moon. These two bodies are the only natural satellites of the earth. Earth sidereal year, is the period in which the earth revolves around the sun and it takes 365.256 days. Besides that, the rotation of the earth’s axis is important seeing that it is responsible for earth seasons. Here are interesting earth facts.
1. Densest planet
Density is among the simplest properties of the existing matter. Each object has a particular amount of energy called mass. These objects occupy a certain space called volume. Therefore, density is the ratio between the mass of objects divided by their volume. Earth is number four as the smallest planet. However, it is the largest, rockiest, and densest. This is because of gravitation, an attractive force that makes tiny particles revolve in the center of the solar system. Another factor is the central star temperature.
2. Rotation of the earth is slowing
Earth rotates around its axis on eastward. Rotation of the earth axis meets its surface on a point called the North Pole. On the other hand, the South Pole is the point that intersects the rotation of the earth axis and Antarctica. The earth rotates for 24hours and it is slowing down hence days were not long in the past. This is because the moon has tidal effects that affect the earth.
3. Centre of universe
According to the geocentric model of astronomy, the earth is the center of the universe. Earth is orbited by the moon, stars, sun, and planets. For example, the sun revolves around the earth each day. Conversely, planets and moon have motions that look like they are revolving around the earth. Moreover, the earth is solid, stable, and unmoving.
4. Covered with water
Earth is watery but you may not know the amount of water in existence. Water is on air, clouds, oceans, rivers, living organisms, plants, and inside the earth. The earth is covered by around 326 trillion gallons of water. This means that 71% is water and the remaining 29% are islands and continents. Also, 96.5% of water is found in oceans in the form of saltwater while 3.5% on freshwater lakes.
5. Earth has three layers
Earth has an internal structure that is divided into three layers. The outer layer is the crust, a solid layer that is highly viscous. The crust is shell-like and can be compared to a boiled egg. It is made up of light elements such as oxygen, silica, and aluminum. The next layer is the mantle, a liquid layer that is less viscous. It is hot, dense, semi-solid, and consists of iron, silicon, and magnesium. Lastly, the inner core is located about three-quarters from the moon. Also, it is extremely hot with a temperature of 5400 degrees Celsius. It has intense pressure that is at least 3 million times more than the earth’s surface. Research claims that there
might be another inner core consisting of iron.