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  • From lakes that actually explode to a twin planet that crashed into Earth once upon

  • a time, we count 15 facts about the little blue planet we like to call home

  • 15 - 24 Hours, • The common saying goes that there's only

  • 24 hours in a day - but that isn't actually true, the Earth spins on its axis for 23 hours

  • and 56 minutesThe reason we add an extra 4 minutes is

  • because the distance in which we've orbited the sun is so great that it takes some extra

  • time just for us to face the sun againAnd since the Earth is spinning slower

  • and slower every few million years, in around 250 million years a typical day will actually

  • last 1.5 hours longer 14 - Gravity Glitch,

  • There is an area in Canada known as Hudson Bay with uneven mass - and where there's uneven

  • mass, there's uneven gravityLong-since melted glaciers once lined

  • the area, but now they're gone and the burden of gravity remains in both the ice sheets

  • and underneath the Earth's crust, leading to lower gravity here than anywhere else on

  • EarthDon't get too excited though - it's not

  • like you'll be able to start moon-jumping around Canada - the difference in gravity

  • is only a 0.005% reduction, so minute that you can't even feel it

  • 13 - Photo, • 65 miles above the atmosphere, the first

  • ever photo of Earth was taken with a camera carried by a V-2 missile in 1946 - it snapped

  • a frame every second and a half and managed to survive re-entry

  • The scientists who reviewed the footage were beyond ecstatic, jumping up and down

  • with joy that they could finally see their own world in a still image

  • Likewise in 1967 the first full-on, colour Earth image was taken by the DODGE satellite,

  • which you can see on-screen here 12 - Ocean Salt,

  • Most of the salt in our ocean comes from rocks on the shores, mainly because rainwater

  • which is naturally acidic breaks down the rock and distributes their components into

  • the waterSeawater salt is so dense that if you

  • were to dissolve all the oceans in the world and spread the remaining salt over all the

  • land on earth, you'd have a 500 foot thick salt layer coating EVERYTHING

  • 11 - Rocks Can Walk, • There exists a flat lakebed in Death Valley

  • known as Racetrack Playa, in which rocks physically move from place to place

  • And it's not just small rocks, but ones weighing tens or hundreds of pounds - the

  • theory goes that these ice-encrusted rocks are flooded by meltwater from the hills

  • This makes everything nice and slick which, along with a hard breeze, allows the rock

  • to travel 10 - Twin Planet,

  • There is a well known theory that at the beginning of Earth's development there existed

  • a smaller twin planet known as Theia, roughly the size of mars

  • • 4.5 billion years ago it crashed into Earth and while most of it was absorbed into

  • Earth's crust, the rest drifted off and formed that celestial body known as the Moon

  • The reason this theory came about is because typically planets of Earth's size don't have

  • moons quite so big, and not to mention various matters found on the Moon are somehow shared

  • with Earth 9 - Heat,

  • Many assume the Sun to be our main source of energy, a life-giving ball of energy to

  • which we are utterly dependent - and that if we ever stopped receiving heat from the

  • sun, the human race would go extinctIn reality, Earth's core is just as hot

  • as the surface of the Sun - between 5,000 to 7,000 degrees celcius

  • In the event of a catastrophe say, sun rays are permanently blocked by clouds and

  • all land on Earth freezes, we can still harness the energy within Earth to keep us alive

  • 8 - Exploding Lakes, • Three lakes in Cameroon, near the border

  • of the Congo named Nyos, Monoun and Kivu - more commonly referred to as the exploding lakes

  • In 1984 on a small stretch of road, a gas cloud appeared and swallowed a great many

  • local villagers walking on their way to work before getting swept away with the wind

  • • 37 people were killed instantly, and they discovered the gas cloud was in fact carbon

  • dioxide released in an explosion from the lakes, which happened to be sitting above

  • volcanic Earth - and continue to do so to this day

  • 7 - Unexplored Oceans, • Even though we've touched down on the

  • Moon and conquered vast mountains, the truth is we've only explored little under 10% of

  • the oceanTo this day we've only discovered near

  • 210,000 underwater species with an estimated 20 million yet to be seen

  • That means a distant fish-human hybrid may indeed have evolved somewhere deep beneath

  • the ocean surface, and mermaids could still be a real thing - either that, or more species

  • of fungus 6 - Supercontinent,

  • Back a long time ago when dinosaurs first roamed the Earth, there existed a supercontinent

  • called Pangaea that merged all the countries of the world together into one landmass

  • But did you know that another supercontinent will form in the next 250 million years?

  • It's name will be Pangaea Ultima, including a subduction of the western Atlantic, the

  • destruction of the Atlantic and Indian basin, rejoining America with Africa and Europe - the

  • centre of this giant landmass effectively a semi-arad desert prone to extreme temperatures

  • 5 - Leaving a Mark, • Nuclear tests in the 1950s continuing

  • to this day have thrown dust into the atmosphere circling our planet - most of it falls down

  • as rain and snow, but some gets trapped in glaciers

  • These glaciers formed over millions of years leave timeline indicators that help

  • scientists date the exact time that piece of ice formed in Earth's history

  • Which means when scientists of the future look at our glacier slice, they'll no doubt

  • shake their heads and whisper a gentle "goddamnit" • That's IF the glaciers survive their rapid

  • melting from global warming - which they aren't 4 - Earth Isn't Round,

  • For a long time in Earth's history, people have believed the world is flat and no doubt

  • you'll find people tell you this even in the comment section of this video

  • But the Earth isn't exactly round either - there's a bulge inside the equator stretching

  • about 20 miles outwards, which actually gives it more of a rotund appearance if you look

  • at it from the right angleSo while it is technically circle, like

  • all bodies that have eaten take away one too many times, the slight gut gives it away

  • 3 - Underwater Gold, • If you were to go exploring in the deep,

  • vast oceans, you might discover some flakes of gold, but did you know there are more than

  • 20 million tons of gold at the bottom of the sea?

  • The only reason we haven't grabbed our scuba gear and excavation equipment is because

  • the gold is spread out over such a wide area, where one litre of water contains just 13

  • billionths of a gram of gold that people don't think it's worth it

  • There currently doesn't exist any efficient way of harvesting this gold - but if we could

  • manage it, we'd have enough to give every single person on earth 9 pounds worth of gold

  • 2 - Largest Living Thing, • Most would point to the Blue Whale if

  • asked to identify the largest living creature on this planet, but there exists another living

  • organism that could easily top itOne mushroom grows fungus which tunnels

  • underground, one particular variety of honey mushroom found in Oregon was discovered to

  • be over 2,200 acres big, stretching all undergroundTry to imagine yourself with body hair

  • spanning over 2,000 football fields and you're able to feel everything that comes into contact

  • with it - and you'll know what it's like to be this mushroom

  • 1 - Super-EarthsEarth has always been a curious place

  • because it's only just barely far enough away from the sun not to get burnt, but not so

  • far that it freezesScientists have been searching through

  • a number of exoplanets, planets that orbit another star other than our sun that happen

  • to be in the habitable zone, not too hot and not too cold - just enough of both to sustain

  • life as we know itSince 2012, several Super-Earths have

  • been discovered considerably bigger than Earth but still in the habitable zone - we've even

  • seen a planet discovered this year that is roughly the same size, could theoretically

  • sustain life and orbits a red dwarfThere's no telling if we'll ever find

  • another Earth - that's a job left to the future generations

From lakes that actually explode to a twin planet that crashed into Earth once upon

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關於地球,你不知道的15件事 (15 Things You Didn't Know About Earth)

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    Furong Lai 發佈於 2021 年 01 月 14 日
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