There is a huge freaking asteroid 2,000 feet long out there in the cosmos called 99942 Apophis. In cosmic terms, 2,000 feet is very small. But what’s so special about this asteroid? It may hit the planet in 2036.
The concern: Within the object’s range of possible fly-by distances lie a handful of gravitational “sweet spots,” areas some 2,000 feet across that are also known as keyholes.
The physics may sound complex, but the potential ramifications are plain enough. If the asteroid passes through the most probable keyhole, its new orbit would send it slamming into Earth in 2036. It’s unclear to some experts whether ground-based observatories alone will be able to provide enough accurate information in time to mount a mission to divert the asteroid, if that becomes necessary.
Timing is everything, astronomers say. If officials attempt to divert the asteroid before 2029, they need to nudge the space rock’s position by roughly half a mile – something well within the range of existing technology. After 2029, they would need to shove the asteroid by a distance as least as large as Earth’s diameter. That feat would tax humanity’s current capabilities.