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  • 10 amazing things you didn't know about the Earth

  • 10. Secret ocean

  • Scientists have discovered a vast reservoir of water located 660 kilometers

  • beneath the Earth’s surface.

  • The underground ocean is hidden inside a blue rock called ringwoodite, which

  • acts like a sponge, trapping hydrogen and water.

  • There is enough water beneath the Earth’s surface to fill the Earth’s oceans three

  • times over.

  • Scientist Steve Jacobsen suggests that the Earth’s surface oceans were first

  • formed when trapped water was driven to the surface by geological activity. This

  • contradicts the widely accepted theory that icy comets deposited water onto

  • Earth.

  • Sources: The Guardian, New Scientist

  • 9. Uneven gravity

  • Many people assume that gravity is distributed evenly on Earth, but there are

  • certain places, such as Hudson Bay in Canada, that actually experience less

  • gravity than other regions of the globe.

  • In Hudson Bay this occurs because there is only a small amount of land mass,

  • due to retreating glaciers on the surface and swirling magma in the Earth’s core.

  • A satellite called theGravity Field and Steady-State Ocean Circulation Explorer

  • was sent into space in 2009 to create a map of the planet’s gravitational field.

  • It mapped Earth’s gravity with extraordinary accuracy and is used by

  • geophysicists to measure ocean circulation, sea-level change, and ice dynamics.

  • Sources: Live Science, New Scientist, Space Daily

  • 8. Longer Earth days

  • Around 620 million years ago, there were only 21.9 hours in a day.

  • Ocean tides generated by the Moon and Sun's gravity have added 1.7

  • milliseconds to the length of a day each century, because they alter the planet’s

  • rotational momentum.

  • The length of the day can also be affected by natural events such as the 2011

  • earthquake in Japan, which actually shortened the length of each Earth day.

  • The quake changed the distribution of the Earth’s mass causing it to rotate

  • slightly faster, decreasing our day by about 1.8 microseconds.

  • Sources: Scientific American, NASA

  • 7. Pangaea

  • Pangaea was a supercontinent that existed during the late Paleozoic and early

  • Mesozoic eras, 300 million years ago.

  • Formed by the movement of Earth's tectonic plates, it began to break apart about

  • 175 million years ago.

  • At this time most of the dry land on Earth was joined in one huge land mass that

  • covered nearly a third of the planet's surface.

  • Geologists believe that due to tectonic plate movements, in 250 million years the

  • Earth’s continents will be merged again into one giant land mass, formPangaea

  • Ultima.’

  • Currently each year Hawaii, which sits on the Pacific Plate, moves nearly three

  • inches closer to Alaska.

  • Sources: Universe Today, BBC, The Blaze

  • 6. Hot in here

  • Over the next 1.1 billion years, scientists predict that the Sun will get

  • progressively brighter and hotter by about 10% compared to now.

  • In 4 billion years, our oceans will evaporate, resulting in a runaway greenhouse

  • effect that will send temperatures soaring above 750 degrees Fahrenheit,

  • rendering life on Earth impossible.

  • In 7.5 billion years, Earth will become a vast desert similar to Mars today and the

  • Sun will expand into a red giant.

  • At this point, scientists predict that the Sun will engulf Earth altogether, meaning

  • the definite end of our planet.

  • Sources: Howitworksdaily, BBC

  • 5. Earth used to be purple

  • There is an astrobiological hypothesis that suggests that Earth used to be purple.

  • Scientists believe that before plants as we know them became dominant, ancient

  • microbes might have used a molecule other than chlorophyll to harness the Sun's

  • rays.

  • The molecule, called retinal, gave Earth’s organisms a violet hue.

  • According to Shil DasSarma, a microbial geneticist from the University of

  • Maryland, chlorophyll gradually replaced retinal because it is more efficient at

  • absorbing light, and thus purple became green.

  • Sources: Astrobio, livescience, Dawn

  • 4. How did life on Earth begin?

  • There are around 8.7 million different species on Earth, but scientists are still not

  • entirely sure how life on Earth began.

  • Most scientists believe that living things developed from molecules that were

  • able to replicate themselves, rather like DNA does.

  • These molecules either came from somewhere further out in space, or they were

  • produced by the conditions on Earth at the time.

  • A new study suggests the latter and argues that the building blocks of life, such

  • as the compounds that would be necessary to create DNA, existed on Earth prior

  • to the creation of the first life forms.

  • Sources: BBC, Live Science, Time, Phys.org

  • 3. Earth is a bumpy globe

  • Despite countless photos of Earth depicted as a perfect sphere, Planet Earth is

  • actually an imperfect bumpy globe.

  • This is because the force of Earth’s rapid rotation on its axis causes it to push

  • outwards at the equator, making it look like a squashed ball.

  • Due to the Earth’s uneven shape, Mount Everest isn’t actually the tallest

  • mountain. If measured from sea level, Everest would top the list, but measuring

  • from the center of the Earth, Mount Chimborazo takes the crown.

  • Sources: Scientific American, Independent

  • 2. Underwater mountain range

  • The longest mountain range on Earth is actually 90% underwater. It is called the

  • mid-ocean ridge system and was formed by the movement of plate tectonics.

  • Surveyed in detail in the 1950s, it stretches for 80,000 kilometers all around the

  • world and is nearly 20 times longer than the longest range on the surface, the

  • Andes Mountains.

  • Furthermore, it consists of thousands of individual volcanoes that sporadically

  • erupt.

  • Around 20 volcanic eruptions occur each year and this causes the formation of

  • 2.5 kilometers of new seafloor.

  • Sources: BBC, Ocean Service

  • 1. Geomagnetic Reversal

  • The Earth’s magnetic field is becoming less stable.

  • Researchers believe that the planet’s inner core is slowly growing, as the outer

  • core cools and solidifies, resulting in more frequent flips of Earth’s magnetic

  • field.

  • In other words, if the polarity of today’s magnetic field were reversed, the North

  • and South markings on all compasses would be 180 degrees wrong.

  • Using fossil records from hundreds of past magnetic polarity reversals, scientists

  • have determined that the reversal of the magnetic poles should not have a

  • dramatic effect on human life.

  • However, some animals, such as pigeons and whales, use the Earth’s magnetic

  • field for a sense of direction. So, if a reversal occurs in their lifetime, they might

  • have to develop different methods of navigation.

  • Sources: NASA, geomag, BBC

10 amazing things you didn't know about the Earth

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10 Things You Never Knew About The Earth

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    Tino posted on 2016/06/14
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