We have been living on Earth. The only planet - from 9 planets that are members of the solar system - which is known to be eligible for life, with a weight of 66 sextiliun (1.000.000.000.000.000.000.000 or 10 ^ 21) tons and 1 trillion cubic kilometers in volume. But have you know the earth is more distant?
Below are 10 facts about the Earth that you might never know. Hopefully useful as an addition to your knowledge.

1. Earth's surface is more subtle than billiard balls
If the Earth depreciated to about the size of a billiard ball, the surface will be smoother than the surface of the billiard balls. Is this true? Let us look further, to the count of the smallest in mathematics.
First of all, how gentle a billiard ball? A billiard ball with diameter of 2.25 inches or about 5.7 cm, and has a tolerance of approximately 0.005 inches or 0.013 cm. In other words, the ball should not be experiencing stress or conflict of more than 0.005 inch or 0.013 cm in its highest position. That's really soft. The ratio of the size of a collision is allowed compared to the size of the ball is 0.005 / 2.25 or about 0.002.
Now we compare with Earth ball. Earth has a diameter of about 12.735 kilometers (on average). By using the comparative subtlety of billiard balls on top - or the Earth is considered as a billiard ball - if no collision (mountains) or pressure (rivers) more than 12.735 miles x 0.00222, or about 28 km in actual size.
Known to the highest point on Earth's surface is the summit of Mount Everest is about 8.85 kilometers, and the Marianas Trench, the deepest point is about 11 km. The figures are still far within the limits of tolerance, which is 28 km. So it has been proven to Earth's surface smoother than a billiard ball.

2. Earth is not round
In general, note that the Earth is round like a ball from thousands of years ago. Eratosthenes even calculated the circle with incredible accuracy!
But it was not as perfect as that. Earth rotates on its axis, and as a result the earth became swollen due to centrifugal force, a force pushing out that you also experience when you are riding in a car that turned left suddenly. Because the rotation of Earth, appears a force out that the maximum in the Earth's equator, making the lumps out in areas such as basketball Katulistiwanya occupied. This form is called a ball with bumps transverse (oblate spheroid).
If you draw a line from north to south pole of Earth, Earth's diameter is 12,713.6 km. If you measure the diameter of the equator as the margins, the length is 12756.2 km, where there is a difference of about 42.6 kilometers. That exceeds the tolerance in billiard balls. So the Earth is softer than billiard balls, but not sebulatnya, had understated the size of Earth.
3. Earth drawn here and there
But pemasalahan not finish up there. Earth also experienced a bruised due to the Sun and Moon. Sun and Moon has a gravitational pull that Earth's pull. As a result there bumps on the surface of the Earth - both on land and at sea - the section closest to the Sun and Moon. The increase or lump due Moon has gravity amplitude (height) with a rough estimate of 1 meter in the water - so-called high tide, and perhaps about 30 cm in the soil. Sun are much bigger than the Moon, but because it is so far away then the resulting increase of about half of it. This is much smaller when compared with the deviations due to the rotation of the earth, but still there.
4. Earth is not really aligned with its geoid If the Earth has infinite elasticity, and the circumstances that the Earth responds by not limited to any pressure, so the shape becomes a strange and distorted (highly elastic gel-like), that's called the geoid. For example, if the entire Earth's surface is water completely - if global warming has resulted in very severe - then the form will be geoid surface. But the continents do not see regularly, so that the surface of the Earth is only approximately a geoid.
Precise measurements of the earth's surface are calibrated against this geoid, but the geoid itself is hard to measure. The best thing we can do now is take the model by using complicated mathematical functions. That is why ESA launched a satellite named Goce (Gravity field and steady-state Ocean Circulation Explorer) on 17 March, to directly determine the geoid's shape.
5. Jumping into the holes that penetrate into the Earth as it tries to orbit into space
We wished to dig a hole through the Earth which berkedalaman 13,000 km, and travel to the center of the Earth. What happened? Whether we can cross the center of the earth and out to the surface of another?
First of all, you will experience continuous acceleration when falling towards its center as drawn, with a total travel time approximately 20 minutes to get there. However, when you try to pass through the center of the Earth to rise to the surface, you will begin to slow and eventually will fall back to its center. Whatever you try will certainly fall, because gravity center of the earth when you were growing increasingly distant from the center point, and acceleration due to gravity is reduced when approached. The speed you need to get past the center point and up to the surface of the earth is about 7.7 km / sec.
In fact, mathematical calculations that control the same movements at the time of orbital objects. The time needed to fall to Earth the same as those needed to return to orbit, if the orbital is really on Earth's surface (orbits slow down as the orbital diameter bigger). Even that strange, it does not matter where you start from the hole, a straight line through the Earth from any point toward the other point (the shortest distance, through the center line of the earth, or elsewhere) to give you time-travel the same, ie 42 minutes or about it.
6. The depth of the earth which affects the heat shrinkage, the surface of the sink, and radioactive decay.
In the past, you, me, and everything on Earth was scattered in a disk around the Sun several billion kilometers. From time to time, all this strewn collected into planetesimals, such as small asteroids, which hit at the same time, some elongated, shaped larger. In the end, after this thing is big enough, then the active pull of gravity with the other. Together, they release kinetic energy in the form of heat, and the young Earth tangible ball that melts. Presto! A heat source appears. With increasing gravity, the force trying to destroy the Earth to form a more solid ball. As you squeeze a hot object. Presto! The second heat source is created.
Since the Earth is still liquid, heavy materials fall to the center and lighter material ejected upward. So the Earth's core contains iron, nickel, osmium, and various other metals. As this material falls, heat is produced, then the potential energy is converted into energy of motion, which is then converted into thermal energy separately.
And most of the heavy elements are radioactive, like uranium. When the proceeds, releasing heat. The calculations are probably more than half of the heat inside the planet.
So the Earth gets hot in them because there are at least four sources. And still hot until now because of earth's crust to be a good insulator. The Earth's crust to prevent heat from escaping efficiently, even after a period of 4.55 billion years of the earth is still a warm place that is not fun.
Sometimes, the amount of heat that flows out onto Earth's surface from an internal source of approximately 45 trillion Watts. About three times the global human energy consumption. If we can keep all the heat and convert it with 100% efficiency in the form of electrical energy, means literally the energy for all mankind. But unfortunately, it can not be done.
7. Earth has five "months" other.
We all know that the Earth has a moon only. But did you know there are four other objects, at least, which is very close to Earth in our solar system. They are not really the moon, but much like the moon.
The largest named Cruithne. The distance is about 5 kilometers from Earth, and has an elliptical orbit that is, a time inside and outside the Earth's orbit around the sun. Cruithne orbital period is about Earth's orbital period, and because the strangeness of this path, then he is always on the same side to Earth from the Sun. From our perspective, it makes a weird form of orbit, sometimes closer, sometimes farther from Earth, but never really far away.
That's why some people say this thing as a "month" of the Earth. But Cruithne actually orbits the Sun, so that is not Earth's moon. Just as the three other objects were found. But "few months" will not harm the Earth, even if they are near the Earth, but their orbits do not physically pass through it. So the Earth remain safe from them.
8. Earth would be a more giant
We may still be safe from collision Cruithne, but space is still littered with many ruins, and the fact that the Earth cuts a wide area of about 125 million square kilometers. When we navigate this material, we accumulate on average 20-40 tons of material per day! Most of tangible dust particles so small that burned down in Earth's atmosphere, such as what is called a meteor. This meteor fragments eventually falling to the ground after being taken by the rain and buried, the river and then drift into the ocean.
40 tons per day may sound like a lot, but it only 0.000000000000000000000002% or 2 × 10 ^ -23 times the mass of the earth. In other words required about 140,000 million trillion years to double the mass of the Earth, then in one year was enough cosmic junk material to fill a full six-storey building.
For the record the Earth is also losing mass, because the atmosphere had a leak due to various different processes. Though still much slower than the increase in mass accumulation, so that its influence remains will double its mass.

9. Mount Everest is not the biggest mountain
The height of a mountain probably has an obvious definition, but would be more accurate if measured from the bottom to the peak point kulminasinya. Mount Everest stretches 8850 meters above sea level, but that from the point first to the general limitation of the Himalayas. Volcano Mauna Kea, Hawaii, 10,314 feet from end to end, although only reaching 4205 meters above sea level, but it is a bigger mountain than Everest.
10. It's not easy to destroy Earth
Maybe you've heard about various ways the destruction of Earth, but actually it is not easy to destroy the Earth.
Let's take the example of the destruction of the evaporating planet. Views of Earth by evaporation like blowing hard, are scattered and can not go back even though there is gravity. How much energy is required, if it is done?
Suppose we take a stone. Upward with a strong throw to the air to escape from Earth. And it will take a lot of energy! Now do continue, once again, kept repeating itself, around 10 ^ 15 times, until the entire Earth down. It takes so much energy! But there are advantages, every stone that we release will reduce the bit gravity of Earth - because the mass of Earth will shrink a rock mass. When gravity is reduced, it means that much easier the next throwing stones into the sky.
Mathematical calculations to calculate how much energy it takes to throw a rock simultaneously, covering also decrease the Earth's gravity. If you make some basic assumptions, the energy required is roughly 2 x 1032 Joules, or 200 million trillion trillion Joules. Quite a lot. For comparison, the number was equal to the sum total solar energy emitted during the week. It is also comparable with trillions of times the destructive energy than all nuclear weapons on Earth.
If you want to vaporize the Earth with nuclear weapons, and blow up a number of all existing nuclear Earth in every one second, then takes 160,000 years to turn the Earth into a gas. And that if you only consider the factor of gravity alone! And there chemical bond energy in the earth, the mutual binding between the material, so it will need another energy.
Even major clashes can not vaporize the planet. A Mars-sized object hit the Earth more than 45 billion years ago, and the remains then fabricated and formed the moon, but Earth still does not evaporate. Even hitting a whole planet into another planet would not destroy it! Of course, the collision of the Earth will reach a molten core, so that permanent damage occurs. But Earth is still there.
Even if the sun will become a red giant, but still not be able to swallow the Earth, would only be harmful to humans only. But the total evaporation will not occur. Because the planets tend to survive, and will remain a safe place to live

 
Source article: http://www.bspcn.com/2008/09/09/10-things-you-don% E2% 80% 99t-know-about-the-earth /
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