Washington: If you are not aware that a giant asteroid the size of a football field flew past Earth over the weekend, you are not alone as even NASA scientists got to know about the flyby only a few hours before it happened, media reported.
NASA scientists noticed the massive asteroid at an observatory in Arizona just 21 hours prior to the flyby, ScienceAlert reported on Tuesday.
The asteroid, designated 2018 GE3, made its closest approach to Earth at around 2.41 a.m. EDT on Sunday, according to a Space.com report.
Travelling around 106,000 kilometres per hour, the asteroid was as far away from our home planet as half the average distance between Earth and the Moon.
NASA has estimated that the asteroid is somewhere between 47 to 100 metres wide, meaning it is roughly 3.6 times the size of the one that cleared 2,000 square kilometres of forest when it exploded over Russia's Tunguska region in Siberia in 1908.
And that particular asteroid was estimated to have produced about 185 times more energy than the Hiroshima atomic bomb, the report said.
"If 2018 GE3 had hit Earth, it would have caused regional, not global, damage, and might have disintegrated in the atmosphere before reaching the ground," SpaceWeather.com reported.
"Nevertheless, it is a significant asteroid, illustrating how even large space rocks can still take us by surprise. 2018 GE3 was found less than a day before its closest approach," said the report.