Home to 7.2 Billion people planet Earth is a 5 billion year old ball of Iron, Oxygen, Silicon, Magnesium, and other trace elements, hurtling through space at 67,000 mph. Earth is a rather incredible place to be, here's some of the most extreme facts about the planet you live on.
Earth used to be purple. From space, land on the Earth's surface appears mostly green. But millions of years ago it would have been purple. Today plants use a green pigment called chlorophyll to harness the sun's rays which gives them a green appearance. But research shows that chlorophyll hasn't been around forever, in fact during the days of early life on Earth plants used to use a more primitive molecule to harness the suns rays. It was called Retinal, and it gave off a violet hue instead of a green one. Meaning all photosynthesising plants on Earth were, at one point bright purple.
But the dominant color on Earth's surface definitely isn't green. When the first astronauts that went into space looked back at our planet, they called it the "Blue Planet". That's not surprising when you consider that Earth's surface is 71% water.
With all that water you would think we would know more about what's down there, but 95% of Earth's underwater world still remains unexplored. That's a remarkable testament to how astonishingly vast the oceans actually are.
Only 3% of water on Earth is fresh water. The remaining 97% is salted water. And what's more, of the 3% of fresh water, 2% of it is frozen in ice sheets and glaciers. Meaning that less than 1% of water on Earth is fresh water found in lakes, rivers and underground.
The Earth's core is as hot as the Sun. The Earth is like an Onion, it is made up of three separate layers, the core, the mantle and the crust. The core is made up of mostly molten iron, bubbling away at an incredibly toasty 6,100 degrees celcius, making it as hot as the surface of the Sun. Despite this intense heat, the very centre of the Earth's core remains solid iron, because of the immense amount of pressure put upon the core from the weight of the rest of the Earth.
There is single mountain range that stretches around the entire globe. Known as the mid-ocean ridge system. It's an impressive range of underwater volcanoes that spans the entirety of Earth's oceans. It was created from volcanic eruptions of basaltic lava that occurs between the Earth's tectonic plates. At a monstrous 60,000 kilometres long, the mid-ocean ridge system is the largest geological feature on Earth. The closest contender above ground is the Andes mountain range in South America, which is a measly 7,200 kilometres in comparison to the underwater giant.
Earth isn't actually a sphere it's a shape known as a geoid. This simply means that the rounded ball bulges outwards at the equator. But what's even more incredible is what causes Earth to be this shape instead of a perfectly formed sphere. Earth spins on its axis at 1,000 mph. Such a high rotational speed exerts an incredible amount of centrifugal force upon the equator, pushing the earth and water around the equator outwards slightly. Giving the Earth somewhat of a spare tire.
Space is dirty. Every day our planet is sprinkled with massive quantities of interstellar fairy dust. 100 tons of space dust and various other debris drifts down into our atmosphere and onto the Earth's surface every day. Most of it comes from other planets and comets.
And finally, in the interstellar scope, Earth is tiny, really tiny. For example, if you compare it to the planet Jupiter, Earth could fit inside Jupiter 1,321 times. And if you think that's impressive, nothing will make you feel more like a microscopic dot in the vast nothingness of space than this fact, Earth could fit inside the Sun 13 million times. But don't get downbeat, Earth is very special and extremely unique. Earth is the only planet we know of that has given birth to life. It has just the perfect conditions, the perfect temperature and proximity to the Sun, it has water and a magnetic field that protects us from the Sun's violent radiation, as well as many other important factors. The chances of all these coming factors coming together to create a planet that can sustain life is this .0000000000000000000001% or 1 in this number 10,000,000,000,000,000,000,000,000. So the fact that we're even here to begin with is a mathematical miracle. And that's what makes Earth so amazing.