We Likely Wouldn’t See a Doomsday Asteroid Until it Was Too Late
How much warning will we really have if a Near Earth Asteroid (NEO) is about to hit Earth? The answer is pretty grim.
“With so many of even the larger NEOs remaining undiscovered, the most likely warning today would be zero,” NASA informs us. We would see nothing at all until suddenly, just as the impact occurred, we noticed a “flash of light and the shaking of the ground as it hit.” Then poof. Compared to the sudden, unanticipated impact, “if the current surveys actually discover a NEO on a collision course, we would expect many decades of warning. Any NEO that is going to hit the Earth will swing near our planet many times before it hits, and it should be discovered by comprehensive sky searches like Spaceguard. In almost all cases, we will either have a long lead time or none at all.”