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3 Things We Don't Know About Earth
Earth Is the third planet in our solar system. It is the largest of the terrestrial planets, the inner rocky planets. It is also the only place in the universe known to harbor life.
Modern humans have lived on earth for about 300,000 years, and most of that time was lived as semi-nomadic hunter-gatherers. Ever since people began looking up at the stars, we have been wondering how this all came to be. Since then we have come up with some pretty good theories to answer most of our questions. But there are some mysteries that we still have not figured out, I will look at 3 of them.
It suddenly struck me that that tiny pea, pretty and blue, was the Earth. I put up my thumb and shut one eye, and my thumb blotted out the planet Earth. I didn't feel like a giant. I felt very, very small.— Neil Armstrong
1. The Ocean Floor.
The surface of Earth is covered with water, about 70% of it. That is equal to about 333 million cubic miles of water! So it may not be much of a surprise that 95% of the ocean floor has never been seen by humans, that is a lot. Also it is thought that about 99% of life is in the ocean. So there are many undiscovered creatures hiding deep in the ocean. Every year scientists are discovering new and strange animals thousands of feet below the surface. The problem is the pressure under all that water. It has become easier with advancements in robotics, but these machines are very expensive. There are many new discoveries waiting in the waters all over the world. And there will be for many years to come.
2. The Origin Of Life.
Life as we know it may be the strangest thing about our planet. There is no known mechanism to turn inanimate matter into self-replicating matter. There are many ideas about the origin of life on our planet. One idea is that deep under the sea, near hydrothermal vents, chemical reactions took place that caused early life to start. Another idea, little ponds on the surface, with the right chemicals, could have formed the building blocks for life. Though my favorite idea by far is the panspermia hypothesis. The idea goes, looking at life on Earth there are extremophiles that can survive things like, extreme heat, cold, and radiation. If some of these got caught on a piece of rock that was ejected from a planet, it could possibly catch a ride to a new planet and thrive.
3. How Many Species.
Earth has many different ecosystems. In each of these ecosystems there are new discoveries waiting to be made. I already talked about the ocean, where about 99% of life could be. But even on the surface, where people have been searching, and categorizing plants, and animals for hundreds of years, there are new discoveries all the time. It is thought that about 85% of species on land, and about 90% of species in the oceans, have yet to be discovered. The total number of species is thought to be around 8 million.
Tree of life.
Mysteries Of The Earth.
Our home in the cosmos still has many things to teach us about the universe. Understanding these things may tell us where life began, or whether or not it is likely that we will find life elsewhere. This blue marble that we are spinning on is a precious thing, there may be no other place like it. On this planet we are spinning at 1,000 miles per hour. We are orbiting the Sun at 67,000 miles per hour. And we are following our sun through the milky way at an amazing speed of over 400,000 miles per hour. So whether you are sitting, standing, walking, or running. You are moving through the universe at unimaginable speeds on this spaceship we call Earth.