“It’s impressively close. I don’t think it’s quite sunk in yet. It’s a pretty big deal,” Associate Professor Michael Brown, from Monash University’s school of physics and astronomy, told The Sydney Morning Herald.
“[If it hit Earth] it makes the bang of a very large nuclear weapon–a very large one,” he said.The rock was flying from the direction of the sun, which is why astronomers failed to detect it, said Brown.
“It was faint, it was close to the sun. It’s been getting closer to us, getting brighter and brighter, and finally, some smaller telescopes have picked it up. Literally, right about now, it’s about 70,000 kilometers (45,000 miles) from Earth,” he said.
Scientists were surprised by the discovery because they had no idea it was moving in our direction. Astroid 2019 OK, also called “City-Killer” is the biggest asteroid to be observed in 2019 so far, according to Astronomy Magazine.
The Herald reported the rock was first detected at the SONEAR Observatory in Oliveira, Brazil, on Wednesday, July 24, 2019.
“SONEAR discovers asteroid that will pass very close to the Earth tonight (July 25th, 2019),” SONEAR, a privately funded observatory, wrote on its Facebook page.
NASA’s Jet Propulsion Laboratory confirmed SONEAR’s discovery, according to The Sydney Morning Herald.
“It would have hit with over 30 times the energy of the atomic blast at Hiroshima,” Swinburne University astronomer Associate Professor Alan Duffy told The Sydney Morning Herald.
‘The PDCO is responsible for providing timely and accurate information to the government, the media, and the public on close approaches to Earth by potentially hazardous objects (PHOs) and any potential for impact,” the website says.