What makes a planet unique? Is it the large size, number of moons, or even raining diamonds? Several planets would fit the criteria. The unique ability that any planet in the known universe lacks is the ability to nurture Life. Let’s take a look at why Earth is called a unique planet.
Our planet seems to bear a wrong name because more than 70 percent of the Earth’s surface is covered by water, and less than a third of the surface rises from these oceans at different heights. Around 20 kilometers lie between the highest mountain peak, the Mt. Everest, and the lowest point of the seafloor in the Mariana Trench.
What is so peculiar about Earth?
Seen from space, the Earth appears to be a blue dot because almost three-quarters of the Earth is covered with water. Although water is transparent in small quantities, from a certain depth, it gets an ever stronger blue shimmer. Because we see the mighty oceans blue, the Earth is also called the blue planet. A lot of salt is dissolved in seawater, so it is not suitable as drinking water. The little freshwater on Earth is frozen mainly in glaciers and ice caps. Only a tiny fraction of the freshwater is in groundwater, in lakes and rivers, or the air.
The speed of rotation is about 1600 kilometers per hour, i.e., over one and a half times the speed of sound. And the speed around the sun on its one-year trip is around 30 kilometers per second. The special position of the Earth in the Goldilocks Zone has enabled a partially technological civilization or, rather, at least as an inhabited planet. It results primarily from the temperature, which in turn depends on solar radiation and the distance from the sun to Earth.
The largest terrestrial planet
With a diameter of 12,756 kilometers at the equator, Earth is the largest of the four earth-like or terrestrial planets Mercury, Venus, Earth, and Mars in the solar system and also has the largest mass. The others are mostly gas giants.
The composition of the atmosphere
One of the main reasons why Earth is called a unique planet is the Earth’s atmosphere. It is made up of around 21 percent of free oxygen in the form of oxygen molecules, 78 percent nitrogen, and around one percent of the noble gas argon. The much-discussed carbon dioxide, on the other hand, is a trace gas with the content of only 0.035 percent. Free oxygen is evidence of biological activity because if you sterilized the Earth completely, all oxygen would have disappeared from the atmosphere after less than 10,000 years. The atmosphere is a kind of spacesuit that protects against the cold of space, provides the necessary breathing air, and also offers (still) adequate protection against the high-energy UV radiation from the sun and the even shorter-wave X-rays and gamma rays from the cosmos. Humanity and the other diverse life forms on this Earth cannot go anywhere else as this is our only home.
The inside of the Earth
We know the inner structure of Earth with high accuracy since its interior can be illuminated with earthquake waves. The surface consists mainly of two types of crust, the oceanic and the continental crust. The oceanic crust is, on average, about 10 to 15 kilometers thick and forms more than two-thirds of the Earth’s surface. The continental crust is much wider, with a thickness of about 40 kilometers on average. The entire Earth’s crust makes up less than one percent of the Earth’s mass. The mantle begins below the crust, which extends to a depth of 2900 kilometers. It consists of dense silicate minerals and represents two-thirds of the Earth’s mass.
The metallic heart of the Earth – The Earth’s Core
The outer core of the Earth begins under the Earth’s mantle. It consists of a liquid mixture of metallic iron and nickel. It reaches a depth of 5100 kilometers. Mass flows and electrical currents generate the Earth’s magnetic field through a generator effect in the liquid metal of the outer core of the Earth. It has not yet been fully understood. Beyond a depth of 5100 kilometers to the center at 6371 kilometers, the solid inner core of the Earth closes, which has the same composition as the outer core of the Earth. To date, no corresponding measurement data are available for the other worlds in the solar system that has the same values.
Our faithful companion – The Moon
Another unique feature of the blue planet is its large natural satellite, the moon, which reaches around a quarter of the Earth’s diameter. Its mass corresponds to approximately 1.2 percent of the mass of Earth. All internal geological activity has long been extinguished on the moon. For several billion years, its surface has only been changed by external influences such as asteroid impacts. The moon is, therefore, a museum of the early days of our solar system.
Suggested Read- Why Is The Atmosphere Essential For Life?
So many special facts are the reason Why Is Earth Called a Unique Planet. Instead of fighting and oppressing others and differentiating the skin color or belief, we should finally understand that we are all traveling through the vastness of the cosmos on the wonderful blue spaceship called Earth.