“…There is no chance of an impact on this pass, researchers stress. But at 1,100 feet (335 meters) wide, 2014 HQ124 could do some serious damage if it slammed into us…Scientists estimates that they’ve found about 95 percent of the potential ‘civilization-enders’ out there — mountain-size asteroids at least 0.6 miles (1 km) across. But there are probably more than 1 million near-Earth asteroids at least 100 feet (30 m) wide, and less than 1 percent of them have been discovered…”

[Read More: Big "Beast" Asteroid Flies by Earth Sunday: What Would Happen if It Hit Us?]