We call a day 24 hours because it’s a clean, reliable number. But Earth isn’t a perfect clock. When our planet formed 4.6 billion years ago, a day lasted a mere six hours. By the time the dinosaurs ...

Just over five years ago, Sarah Baker created an Instagram account that they hoped would evolve into something more. A couple of months later, they had connected with some other activists and ...

Add Yahoo as a preferred source to see more of our stories on Google. Earth is spinning faster this summer, leading astronomers to notice that some days have clocked in at slightly less than the ...

An asteroid entered Earth's personal space bubble last Thursday. Astronomers from the European Space Agency recorded the second closest flyby of Earth on Sept. 30, dubbing the floating space rock 2025 ...