Zooming through space with its only surviving moon in tow, this marvellous planet has lots of sensational scientific secrets!
1. It came from the sun
Earth formed by accretion from the solar nebula, a disk-shaped mass of dust and gas left over from the formation of the Sun, which also created the rest of the solar system. Gravity slowly gathered this gas and dust together into clumps that became asteroids and small early planets called planetesimals.
2 The Earth may have once had two moons
Some astronomers now theorise that Earth once had a second moon, until it made the fatal mistake of smacking its big sister. For a while when the Earth was young, they posit, it had a big moon and a smaller “companion moon”. One day that smaller moon collided with the bigger one in what astronomers are calling the “big splat.”
3 It’s extremely hot in the core
The Earth’s core is divided into two parts, a solid inner core and a liquid outer core. The temperature of the Earth’s inner core is approximately 6000 degrees Celsius.
4 The crust varies in depth
The crust ranges from 5-70km in depth and is the outermost layer. The thin parts are the oceanic crust, which underlie the ocean basins (5–10 km) and are composed of dense rocks like basalt. The thicker crust is continental crust, which is less dense and composed of rocks like granite.
5 The Earth is whizzing through space
While it may feel as though we are sitting still, in fact the Earth is moving around the Sun at 107,826 km per hour.
6 The continents have moved around
The Earth’s land masses were once super continents which have since broken apart to form the continents we know today. Some 300 million years ago, there was just one continent, a massive supercontinent called Pangaea. And thus there was just one giant sea, called Panthalassa.
7 The landscape has an interesting backstory
While the shifting slabs of rocks called tectonic plates are unseen to us, some of their effects are monumental. The Himalayas, along the border between India and Tibet, began to form between 40 million and 50 million years ago, when India and Eurasia collided.
8 The sky can be magical
Auroras occur when charged particles from the sun are funnelled toward Earth by the planet’s magnetic field and collide with the upper atmosphere near the poles. They are more active when the sun’s activity peaks during its 11-year solar weather cycle.