Earth is the outermost planet in the solar system and the only other celestial object known to host and support life, including plant and animal life. About 29.2 percent of Earth’s surface is water containing oceans, seas and lakes. The remaining portion of the planet is land. It is one of the most common planets in the solar system and is very dry and inhospitable to living things. About two-thirds of the Earth is land, and it receives about half of its sunlight.
The planet’s atmosphere surrounds Earth as a large envelope. Because of its extremely dense atmosphere, Earth cannot freeze or boil water. Instead, it has an average temperature that varies by about one to two degrees above Earth’s freezing point. Because of this atmosphere, Earth cannot support life as we know it, but it does have many natural resources that provide food, fuel, water and shelter for life forms.
Water is essential to life, both on Earth and in the universe. About 70 percent of the Earth’s total water supply is located on the surface of the planet. The water vapor in the air traps heat near the Earth’s equator, thus causing the planet’s temperate climate. Another portion of the atmosphere called the ionosphere, provides a layer of protection against solar wind. The rest of the Earth’s atmosphere is mostly water vapor.
One type of planet is called an “ice planet.” Because there is not enough of oxygen in Earth’s atmosphere to support life, the majority of earthlings are only found on the surface. The majority of earthlings live in the ocean, where they breathe air that is less dense than the Earth’s atmosphere and therefore is not humid. Oceans have some of the most amazing features in the solar system. They are filled with a variety of sea animals, including fish, crabs, whales and octopus. Some of the most beautiful objects in the universe are found around the oceans – including space junk, icebergs, viruses and microbes.
Astronomy is a field that uses the stars, the moon and planets to study the makeup of our earth. It is one of the few scientific fields that get their information from nature. Astronomy is one of only a few natural sciences that have made great strides forward by harnessing the power of the planet around us. Astronomy is the study of celestial bodies such as the sun, moon and planets. It is a science that has created many imitations, much like any other scientist might create a creation.
Although most people are familiar with the planet Venus, our earth is actually one of only two planets around which scientists have detected water. Scientists believe that the presence of water vapour around the earth is caused by an atmosphere that is too hot. The presence of water vapour around the planet was first discovered by satellites in the 1970’s. The detection of water around the earth has led to the formation of theories about the origins of life on earth, and it has also led to the development of a technology that allows us to hunt for water molecules around the world.