Thinking the Earth is flat has certainly gone out of fashion since science revealed its spherical shape centuries ago - that is, unless you spend any time the dimmer depths of Twitter.
But maybe the original theory is not as wrong as we think.
According to new research, Earth was flat 4.4 §billion years ago and almost completely covered in salt water.
But this 'flat' does not mean like a plank of wood, but rather it was flat across the entirety of the globe's surface. It is thought that there were no mountains or gradients at all.
Scientists came to this result after analysing the oldest rocks ever found, in Western Australia. Studying tiny zircon mineral grains within the rocks was key to their understanding.
"The history of the Earth is like a book with its first chapter ripped out with no surviving rocks from the very early period, but we've used these trace elements of zircon to build a profile of the world at that time," lead researcher Dr Antony Burnham, from The Australian National University, told Metro. "Our research indicates there were no mountains and continental collisions during Earth's first 700 million years or more of existence – it was a much more quiet and dull place.
"Our findings also showed that there are strong similarities with zircon from the types of rocks that predominated for the following 1.5 billion years, suggesting that it took the Earth a long time to evolve into the planet that we know today."
The study, published in the journal Nature Geoscience, showed that sediment melting, which occurs with major continental collisions and results in the creation of mountains, did not occur during our planet's early stages.
The zircon grains being studied were found preserved in sandstone rocks in the Jack Hills and date back to when the Earth was *only* 160-million-years-old.
