So called human-built megastructures may actually be slowing down the Earth's rotation. This isn't exactly new information, but it has recently been making the rounds again, especially on social media ...

It's even changing how long a day is ...

Add Yahoo as a preferred source to see more of our stories on Google. (cokada/iStock/Getty Images) Alien megastructures built to harvest stellar energy or alter the orbits of stars may be physically ...

Around 2.5 million years ago, our planet looked very different to how it does now. Not only did woolly mammoths traverse the terrain alongside Stone Age people, our planet was undergoing a series of ...