字幕表 動画を再生する 英語字幕をプリント • 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 minutes • The 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 again • And 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 gravity • Long-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 Earth • Don'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 water • Seawater 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 extinct • In 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 ocean • To 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 angle • So 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 it • One 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 underground • Try 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-Earths • Earth 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 freezes • Scientists 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 it • Since 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 dwarf • There's no telling if we'll ever find another Earth - that's a job left to the future generations
B1 中級 地球について知らなかった15のこと (15 Things You Didn't Know About Earth) 205 8 Furong Lai に公開 2021 年 01 月 14 日 シェア シェア 保存 報告 動画の中の単語