Airplane-sized asteroid detected at 11th hour sneaks up close, whizzes past Earth

On Thursday, 25 July, an asteroid about the size of an airplane passed really close to the Earth. Scientists barely noticed it in time, but luckily, there was no threat from the space rock this time around. Named 2019 OK, the asteroid is huge — estimated to be around 57 to 130 m wide and moving very fast. It came within 73,000 km from Earth that is a quarter of the distance between the Earth and Moon.Michael Brown, Melbourne-based observational astronomer and associate professor at Monash University told The Washington Post, "It snuck up on us pretty quickly. People are the only sort of realising what happened pretty much after it’s already flung past us."How did it go unnoticed? Especially when there are teams of astronomers specifically tasked with keeping track of near-Earth Objects (NEOs) is space? The presence of this object was noticed early in the week by a team in Brazil and the US, and later confirmed by NASA. Information on this NEO was published hours before it whizzed past us.[caption id="attachment_7073151" align="alignnone" width="1280"]

Representational image. Credit: Pixabay[/caption]The reason that this asteroid missed being detected, according to The Print, could have been the speed and size it was traveling at. It was going too fast, at 24 km per second, and was too small for astronomers to notice it. Asteroid 2019 OK also has an elongated orbit that stretches from Venus to Mars, which means that it is not in the Earth's vicinity for a long period of time and could evade detection. It was also coming towards us from the direction of the Sun, which made it hard to observe it.Lastly, the asteroid was coming towards Earth from the direction of the Sun, making it extremely hard to visually identify it. This is the first time that an asteroid this large fell out of the radars of all the national space agencies. While 2019 OK is not big enough to destroy the planet, it is in no way harmless. It could have wiped out an entire city, which would mean the death of millions of people."It would have hit with over 30 times the energy of the atomic blast at Hiroshima," Alan Duffy, an astronomer at Swinburne University told the Sydney Morning Herald.