The Moon Is Drifting Away From Earth—Here’s Why It Matters

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The Moon is slowly leaving us. Every year, it drifts about an inch and a half farther away, a detail scientists confirm by bouncing lasers off mirrors Apollo astronauts left behind. It’s not something you’ll notice, or even be alive for, but it’s happening all the same.On average, the Moon sits 239,000 miles from Earth. Its orbit isn’t a perfect circle, so the distance shifts by about 12,000 miles every month. That wobble is why some full moons look bigger and brighter and get hyped as “supermoons.” But the long-term story is stranger: tides are pushing the Moon outward, and Earth is paying the price with ever-so-slightly longer days.The Moon pulls harder on the side of Earth that faces it, which makes the oceans bulge toward its gravity. Since Earth spins faster than the Moon circles us, those bulges get dragged slightly ahead, and that forward tug gives the Moon a little boost. With each tiny boost, its orbit widens and it drifts a bit farther away, while Earth slows down in return. We can even see proof of this in ancient fossils—clam shells from 70 million years ago show daily growth lines that reveal a day lasted only 23.5 hours back then.The Moon started much closer. Most astronomers agree it formed about 4.5 billion years ago after a planetary collision. Back then, it would have loomed huge in the sky. Imagine eclipses so oversized they might have felt apocalyptic.The Moon Is Moving Away From Us—Here’s How It Impacts EarthLooking ahead, the retreat won’t matter much in our lifetime, or for millions of years. Eclipses will still line up, tides will still swell and crash, and days will still fit into the 24-hour cycle our bodies are wired to. But if you fast-forward billions of years, Earth and the Moon may eventually lock into sync, forever showing the same faces to each other. That’s when the drifting would stop.The Sun won’t let it get that far, though. In about a billion years, it will burn hotter and boil off the oceans, ending the tidal pull that keeps nudging the Moon away. A few billion years after that, the Sun swells into a red giant, erasing the entire system.The Moon’s slow escape is one of those cosmic facts that makes you feel both small and lucky. We get to watch a planet and its satellite in a rare, fleeting phase of balance—close enough for eclipses, far enough for tides—before the clock inevitably runs out.The post The Moon Is Drifting Away From Earth—Here’s Why It Matters appeared first on VICE.