There’s a reason we only ever see one side of the Moon. It’s tidally locked to the Earth, presenting only one side to us as it orbits around the planet. Tidal locking is a fate that befalls lots of ...

Tidal locking is the phenomenon which sees a moon appear fixed in place around a planet, with only one side being visible. This happens when the rotational period - time it takes to spin 360° - is the ...

Even a thin atmosphere can keep a planet spinning freely, giving it a day-and-night cycle like Earth's, say astronomers in Canada and France. The result implies that many of the planets lying within ...