A boulder-sized asteroid designated 2018 LA slammed into Earth's atmosphere on 2 June Saturday after it was determined to be on a collision course with Earth.
The asteroid that was comparatively tiny, was estimated to be only about 6 feet (2 meters) across, was first discovered by the NASA-funded Catalina Sky Survey, operated by the University of Arizona.
Although there was not enough tracking data to make precise predictions ahead of time, a swath of possible locations was calculated stretching from Southern Africa, across the Indian Ocean, and onto New Guinea.
Reports of a bright fireball above Botswana, Africa, match up with the predicted trajectory for the asteroid. The asteroid entered Earth’s atmosphere at the high speed of 10 miles per second (38,000 mph, or 17 kilometres per second) at about 16:44 UTC and disintegrated several miles above the surface, creating a bright fireball that lit up the evening sky. The event was witnessed by a number of observers and was caught on webcam video, NASA said.
“This was a much smaller object than we are tasked to detect and warn about,” said Lindley Johnson, Planetary Defense Officer at NASA Headquarters. “However, this real-world event allows us to exercise our capabilities and gives some confidence our impact prediction models are adequate to respond to the potential impact of a larger object.”
“The discovery of asteroid 2018 LA is only the third time that an asteroid has been discovered to be on an impact trajectory, said Paul Chodas, manager of the Center for Near-Earth Object Studies (CNEOS) at JPL. “It is also only the second time that the high probability of an impact was predicted well ahead of the event itself.”
The first event of this kind was the impact of asteroid 2008 TC3, above Northern Sudan on October 7, 2008. The second predicted impact event was for asteroid 2014 AA, hours before impact on Jan. 1, 2014, in the Atlantic Ocean. The Catalina Sky Survey has been responsible for discovering all three of these small asteroids on impact trajectories.