Our planet is constantly spinning. If you ever need to check this is true, just look and see the Sun as it changes position in the sky – the Sun is actually staying put and it’s us that’s moving! Earth is constantly spinning on its axis, completing a full rotation every 23 hours and 56 minutes. Amazingly, the inhabitants of Earth (us included) aren’t able to feel this spinning at all because everything around us (including the Earth’s atmosphere) is rotating too! If Earth ever suddenly slammed on the cosmic brakes, we’d know about it pretty quickly as the atmosphere would keep travelling at its original speed, wiping the surface of the planet clean in the process.  

All this information makes the fact that Earth is slowing down a little worrying. But there’s no need to panic, the deceleration is only tiny, and that’s all thanks to the Moon and its pull on our tides. Roughly every 100 years, the day gets about 1.4 milliseconds (or 1.4 thousandths of a second) longer. No need to go changing your clocks just yet!

The speed of the Earth’s rotation at the equator

Earth’s speed as it orbits the Sun.

A long way round

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Although they’re staying put relative to Earth’s orbit, both the Sun and the solar system are actually moving at 720,000 kilometres per hour as they travel around the centre of the Milky Way galaxy. But even at this incredible speed it is still going to take about 230 million years to travel all the way around the galaxy. That’s a long road trip!

Slowpoke

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Earth slowing down may be a gradual thing, but if you add up all those days and years it can make a huge difference. At the time of the dinosaurs, Earth would complete a single rotation in just 23 hours, we’ve added a whole 56 minutes to the day since then!