When 2018 LA reached Earth, it was traveling very fast at around 10 miles per second (38,000MPH) and disintegrated in the atmosphere on impact.
However, NASA excuses itself saying that "this was a much smaller object than we were tasked with detecting and warning", according to Lindley Johnson from the NASA's planetary defense. The officer added, "The modern facilities, capabilities, and the models for impact prediction have potential to predict the impact of larger objects".
Paul Chodas of the Center for Near-Earth Object Studies (CNEOS) at JPL points out that 2018 LA is just the third time that an asteroid has been identified to be on a trajectory for impact.
The camera, which Swanepoel said faces to the NW, captured the entry of the asteroid at 6:49 p.m. local time, and according to the Minor Planet Center, it exploded at an altitude of around 50 kilometres above the ground. Though Asteroid 2018 LA didn't cause any damage, it surprised the astronomers as they were able to spot it shortly before it entered the atmosphere.
But smaller asteroids which could wipe out a city might only be detected hours or days before they smash into our planet.
It shows that the tracking systems are getting better, NASA officials said.
One such larger object was the asteroid that went completely undetected until it collided with the atmosphere over Russian Federation in 2013, creating a shock wave that blew out thousands of windows in the town of Chelyabinsk ans caused a number of injuries.
With more telescopes pointed at the asteroid, it became apparent that there may be an impact, Brown said.
In addition to monitoring the Earth, NASA also tracks the asteroids from space. However, the asteroid of 2008 was detected nineteen hours before it struck the sky over Sudan. The second predicted impact event was for asteroid 2014 AA, which was discovered only a few hours before impact on January 1, 2014, in the Atlantic Ocean, leaving too little time for follow-up observations. These smaller asteroids manage to slip into the atmosphere on occasion, where they're usually spotted as fireballs streaking across the sky.