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 the ‘Gravity 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, form ‘Pangaea

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