Earth's life
the moon
The moon is a large Earth-like satellite, with a quarter of the diameter of the planet. The moon is the largest satellite in the solar system, in relation to the size of its planet, and the orbits around other planets are called moons after the Earth's moon.
The gravity between the planet and the moon results in a tidal phenomenon on Earth. This same effect on the moon led to a tidal block: the period of its rotation is the same as it takes to orbit the Earth. As a result, it always faces the planet with only one face. As the moon orbits the Earth, the sun illuminates different parts of its face, resulting in different lunar phases. The luminous part of the moon is separated from the dark part by the solar line between the illuminating part and the dark part. Due to the tidal interactions that occur on Earth's surface, the Moon is about 38 millimeters away from the Sun a year. Over millions of years, these simple changes - in addition to increasing the length of the day on the planet by 23 milliseconds a year - will bring about dramatic changes.
For example, during the Devonian Period (about 410 million years ago) there were 400 days a year and each day lasted 21.8 hours. (32) The Moon significantly affects the evolution of life on Earth by helping to moderate the planet's climate. Both ancient biology studies and computer simulations show that the tilt of the Earth's axis and its stability in this situation is caused by tidal interactions with the moon. Some theorists believe that without this constancy in the Earth's axis versus the torque caused by the Sun and other planets on the eclipse at the equator, the axis's rotation may be randomly unstable - leading to massive changes of the planet over millions of years. Like Mars. If the Earth's axis of rotation comes close to the surface of the Sun's apparent circle of circles, it can lead to very harsh weather due to the very large seasonal variations that will occur. Scientists studying planets and celestial bodies who have studied the impact of this on the planet have predicted that this could lead to the death of all large-scale animals and the destruction of plant life.
But this is still a subject of controversy, and it may be decided by future studies of Mars - a planet with a period of rotation and inclination of its axis like the planet, but not followed by a large moon, and its core is not liquid.
Observing the moon from the planet, it is far enough to appear in the form of a disc with a clear shape like the sun. It is worth noting that the angular size (or stereoscopic angle) of these two objects is identical because, although the diameter of the sun about 400 times larger than the diameter of the moon, it is also about 400 times the distance from the Earth that the distance from the moon from the Earth.
This allows a total eclipse and annular eclipse to occur on the Earth's surface.
The theory of the impact of the impact of the giant body of the most accepted theories that explain the emergence of the moon. According to this theory, the moon was formed as a result of the collision of a primitive planet the size of Mars called the "Thea" planet Earth in its early stages. This (among other assumptions) explains the relative lack of iron and volatile elements on the moon, as well as the fact that the moon's composition is almost identical to that of the Earth's crust.
Earth's life
A planet that is fit for life is called habitable even if it does not. The Earth provides the basic conditions necessary for the presence of water and a suitable environment in which organic molecules can accumulate and the energy needed to support and promote food metabolism. Several factors contribute to the conditions necessary to establish life on the planet.These factors include the distance of the planet from the sun, its movement in its orbit, its instability, its rate of rotation, its deviation from it, its geological history, its permanent atmosphere and its protective magnetic field.
biosphere
Life forms on the planet are sometimes said to represent the biosphere. In general, it is believed that the biosphere began to develop about 3.5 billion years ago. The planet is the only place in the universe where life exists. Even more, some scientists believe that places suitable for life such as Earth are rare in the universe. The biosphere is divided into a number of biotic environments in which a large number of similar plants and animals live. Factors separating vital environments include the latitude circle and the height of land from sea level. Terrestrial biota in the Arctic, Antarctic or Highlands is free of any animal or plant life, while the largest variety of life forms at the equator.
Exploitation of land and natural resources
The Earth provides the resources necessary for man to use it to achieve useful goals. Some of these resources are non-renewable, such as mineral fuels, and are not recoverable in a short period of time. Large quantities of fossil fuel deposits were obtained from the Earth's crust consisting of coal, oil, natural gas and methane compounds. Humans used these deposits to produce energy as a raw material for chemical reactions. Mineral raw materials are also formed in the Earth's crust through the process of the formation of earth ore or minerals from the erosion of its layers and the movements of geotechnical plates.
These materials are rich sources of many minerals and other useful elements.
The Earth's biosphere provides many vital products for humans, including but not limited to: food, wood, drugs, medicines, oxygen, and the re-exploitation of many organic waste and residues. The land-based ecosystem depends on the presence of soil surface and clean water, while the ocean ecosystem relies on dissolved nutrients that have been swept away from land.
Humans live on land through the use of raw building materials in the construction of housing shelters. In 1993
Human land use rates are as follows:
Use drawdowns for percentage land
Agricultural lands 13.13%
Permanent crops 4.71%
Permanent pastures 26%
Forest 32%
Urban areas 1.5%
Other uses 30%
In 1993, the area of irrigated land was estimated at 2,481,250 km².
Natural and environmental hazards
Large areas of the Earth are exposed to extreme weather conditions such as cyclones, tropical storms and tropical cyclones. Many places are also affected by earthquakes, landslides, tsunamis, volcanic eruptions, tornadoes, troughs, snowstorms, floods, droughts and other natural disasters.
In addition, many human-populated areas are exposed to many types of human-induced pollution such as air and water pollution, acid rain, toxic substances and the disappearance of plant life (due to many reasons, including overgrazing, deforestation, desertification), disappearance of wildlife and extinction. Some animal species, soil erosion, lack of some useful elements, depletion of soil and the emergence of alien organisms.
Scientists agree that there is a close link between human activities and global warming due to increased carbon dioxide emissions from factories and from the increasing emissions of hydrocarbons. Earth's population of about 6 billion now has about 500 million cars and buses, all of which emit carbon dioxide and other harmful gases, all of which increase and accumulate these gases in the atmosphere. This is expected to lead to dramatic changes on Earth such as rising temperatures, melting glaciers and melting Antarctica, which will lead to an increase in water levels in the oceans and seas which means that countless islands and all lowlands such as the Netherlands will be doomed. Drowning. Severe temperature changes increase the intensity of hurricanes and hurricanes, and increase the amount of destruction they generate in return.
Human Geography
The study of cartography and geography is among the sciences that have been dedicated throughout history to describe the earth. Surveys (locating and spacing between them) and navigation (locating and orientating objects) appeared alongside these two flags - providing accurate information. The world population in November 2008 was about 6.740 billion people. Indicators show that the global population density will reach 7 billion in 2013, and in 2050 this number will rise to 9.2 billion. Most of this population growth is expected to be in developing countries. Population density varies from one place to another globally, but increases significantly in Asia. By 2020, it is expected that about 60% of the world's population will live in cities rather than in the countryside. Three-quarters of the Earth's surface is covered by the oceans. In addition, half of the land will be either a desert (14%), and the remainder will be heights and mountains (27%) or inappropriate terrain for humans to live on. The northernmost of the human colonies is the city of Alert on the island of Alzmir in Nunavat, Canada (at 82 ° and 28 minutes longitude), the southernmost of which is the Antarctic Amundsen Scott Station (90 ° S).
Sovereign States occupy all land on the planet, except for some parts of Antarctica. In 2014, there were 206 independent sovereign States, including one hundred and ninety-three United Nations Member States, occupying land. Historically, the earth has not been ruled by a single government in control of the entire world, despite numerous conflicts between nations for world domination, but all these attempts have failed. The United Nations is a global organization working to resolve conflicts between states and thus avoid armed conflicts. However, it is not considered a global government. Although the United Nations offers a means of enforcing international law and although there is sometimes unanimous approval by its members for military intervention, it is essentially a forum for international diplomacy. The first man to orbit the Earth was Yuri Gagarin on April 12, 1961. In 2004, 400 people toured outer space and returned to the Earth's orbit, 12 of them on the moon. Persons who live in space for a long time are employees of the International Space Station, and the crew of the space station, which consists of three people, is replaced every six months. The longest man's journey to outer space was in 1970 when the crew of the Apollo 13, a three-person crew, traveled 400,171 kilometers away from Earth's surface.
In human culture
The English name "Earth" is derived from the word "erda" which is of Anglo-Saxon origin, which means the soil or surface on which we walk. The word was then distorted to "eorthe" in ancient English, until it reached "erthe" in medieval English. The planet's astronomical symbol is two intersecting lines around it.
The Arabic word currently used to describe the planet Earth is used in the Arabic language since at least the fourth century AD, and is mentioned in the Koran about 444 times.
The land was often elevated to worship or sanctification and made gods. In many cultures, mother gods, also called Mother Earth, were portrayed as the goddess of fertility. Creation myths in many religions recall the story of the creation of the earth by a group of supernatural gods. Many religious groups emphasize, in Christian doctrine or Islam,
The various interpretations of how the earth is created in the Scriptures are a reality and should be considered in line with the discoveries of modern science or replaced by traditional scientific interpretations of the earth's origin, origin and evolution. Scientific and other religious communities oppose such interpretations.
One of the most prominent examples of this controversy over the genesis of creation.
The earth was once thought to be flat,
But this belief was altered and replaced by the belief in the spherical Earth because of observations of scientists and orbiting the Earth. Man's perception of the Earth has changed considerably after he invaded outer space and made many trips around it. This is reflected in the increasing environmental movement on the extent of human influence on the planet. In this context, the establishment of a World Earth Day aimed at raising awareness and concern for the environment of the planet.
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