'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'.
An asteroid turned into a blazing fireball as it disintegrated over southern Africa last weekend, just hours after it was first spotted.
If one of them comes hurtling to Earth, we could have only days, if that, between when it is spotted and when it hits-and that result would be more devastation than dazzling. Later calculations showed the rock, dubbed 2018 LA, hit the top of the discernible atmosphere at a blistering 17 kilometres per second (38,000 mph) and broke apart several miles above the surface.
However, since the asteroid was determined to be so small and therefore harmless, no further impact alerts were issued by NASA.More news: Petrol prices start to fall after hitting four-year high in Australia
Saturday's asteroid was first discovered by the NASA-funded Catalina Sky Survey, located near Tucson, Arizona. Those data were passed along to the Center for Near-Earth Object Studies where an automated program known as Scout confirmed the impact trajectory.
Trajectory path of ZLAF9B2 (2018 LA) plotted across Oceania, the Indian Ocean and Africa.
Video posted on YouTube, from a farm just across the border in South Africa, showed a fireball swiftly descending and getting bigger, and then a blinding flash in the sky. According to CNEOS records, the asteroid's distance from Earth's centre, at closest approach, was calculated to be 5,874 km, which is well inside the planet's radius of 6,371 km. The smallest asteroids like 2018 LA are the hardest to spot, but also the least likely to do any damage. According to NASA, the impact created a bright fireball in the sky at about 6:44 p.m. local Botswana time (12:44 p.m. ET).
NASA officials said the scramble among scientists and observers of the small asteroid was merely a good training exercise.More news: Djokovic in 9th French Open quarterfinal in row
It was much smaller than the meteor that exploded over Chelyabinsk, Russia, in February 2013, which was an estimated 60 feet wide.
"It is also only the second time that the high probability of an impact was predicted well ahead of the event itself", said Chodas.
The Minor Planetary Centre said 'object no longer exists (in its original form), following its entry into the Earth's atmosphere on 2 June 2018. 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.
There have been only two other times when asteroids were detected so soon before impact. The same asteroid hunter, Richard Kowalski, made all three discoveries.More news: Apple unveils the six new features on your iPhone
In 2008, 13-foot asteroid 2008 TC3 disintegrated over the skies of northern Sudan approximately 19 hours after discovery.