At the time of its discovery, 2018 LA was nearly as close to Earth as the orbit of the moon, "although that was not initially known", stated NASA officials.
Asteroid trackers at NASA and elsewhere quickly determined the rock - about 6 feet across (2 meters) - was too small to pose any danger. Here's how to know for sure!
This is only the third time that an asteroid with an impact trajectory has been discovered, and only the second time that such a "high level of probability of an impact was predicted well ahead of the event itself", according to Paul Chodas, manager for CNEOS.
The small, Earth-bound asteroid discovered this weekend is no longer a threat. That trajectory plot was the first hint that 2018 LA could hit Earth. It appeared as a bright streak coming in force with a spectacular fireball.
Earth’s Days Are Getting Longer-Thanks to the Moon
So, Meyers and his colleagues had to find a different way to account for what happened in the solar system billions of years ago. That is not less than partly as a result of the moon was nearer and adjusted the way in which Earth spun round its axis.
Astronomers need long-term data to accurately determine the trajectory of asteroids and, as 2018 LA had just been identified, they didn't have much to go on.
Only twice before has a small asteroid been detected hours before colliding with Earth.
Asteroids Are big debris left over from the creation of the solar system.
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.
While there is a good chance of finding meteorites on the ground from the impact of 2018 LA, any fragments of the asteroid that made it to the surface would have been slowed considerably by their interaction with the atmosphere. Hours later, it struck the atmosphere. It would most certainly hurt if someone was unlucky enough to be hit by one of these, but it's unlikely to cause a serious injury. Only two other instances come to mind, according to JPL. However, the asteroid of 2008 was detected nineteen hours before it struck the sky over Sudan.
Smaller objects are fainter and more hard to spot in a large sky, though efforts like the NASA-funded Catalina Sky Survey are increasingly able to search a wider field of sky to find these somewhat elusive objects. Luckily, 2014 AA struck over the Atlantic Ocean, thousands of miles away from the nearest landmass, Sky & Telescope reported at the time.