Some more Why Files

[727Sky]

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Asteroid Apophis is Coming | Ground Zero: California On April 13, 2029, an asteroid named Apophis will pass closer to Earth than our communication satellites. For the first time in human history, millions of people will watch a mountain-sized space rock race across the night sky. NASA says we're safe, but Apophis is just the beginning. Scientists estimate 25,000 city-killer asteroids cross Earth's orbit, and they've only found half of them. The other 13,500 remain completely hidden, somewhere in the darkness of space. Every three days, fragments from ancient comets bombard our planet. Just 12,800 years ago, a cosmic impact reset human civilization and triggered a freeze that lasted over a thousand years. The evidence is buried in rock layers across four continents. Today, we have the technology to fight back, but time is running out. The question isn't whether another impact will happen—it's whether we'll be ready when it does.