قالب وردپرس درنا توس
Home / Science / The scientists have almost missed the approach of the "City Killer Asteroid".

The scientists have almost missed the approach of the "City Killer Asteroid".



Alan Duffy was confused. On Thursday, the astronomer's phone was suddenly flooded with calls from reporters who wanted to hear about a large asteroid that had just flown over the earth, and he could not figure out "why everyone was so alarmed."

"I thought It was "Duffy, who is also senior scientist at the Royal Institution of Australia, told the Washington Post that he needed to worry about something we knew would come." Forecasts had already predicted that a few asteroids would pass relatively close to Earth this week.

Then he looked at the details of the space rock asteroid 201

9 OK.

"I was stunned," he said. "This was a real shock."

This asteroid was not an asteroid that scientists pursued, and it seemed to have come out of nowhere, "said Michael Brown, a Melbourne-based observing astronomer, opposite the post office, according to NASA, the rugged rock was large, 100 meters wide and moving quickly on a path that took him to a distance of about 70,000 kilometers from Earth, which is about a fifth of the distance to the moon and what Duffy regards as "unpleasantly close."

  • Apollo 11 astronauts were exposed to "degrading experiences" when they returned to Earth 50 years ago

"said Brown, a professor at the Australian Monash University of Physics and Astronomy. "People only understand what happened after it happened to us already."

The presence of the asteroid was discovered earlier this week by various astronomy teams in Brazil and the United States. Information about his size and path was posted a few hours before his rebound to Earth, Brown said.

"It shook me from my morning complacency," he said. "It's probably the largest asteroid that has come so close to Earth for a number of years."

So how did the event go almost unnoticed?

First there is the problem of size, said Duffy. Asteroid 2019 OK is a sizeable boulder, but not nearly as big as the ones that can trigger an event like dinosaur extinction. More than 90 percent of these asteroids, which are 1 kilometer, 0.62 miles or more in size, have already been identified by NASA and its partners.

"Nothing of that size is easy to spot," Duffy said about the 110-meter mark. wide asteroid. "They really rely on reflected sunlight, and even with the next approach, it was barely visible with binoculars."

Brown said the "eccentric orbit" and the speed of the asteroid are likely to be factors in why he saw it in front of him. His "very elliptical orbit" brings it "from beyond Mars into Venus's orbit", which means that the time spent near the earth, where it is detectable, is not long. The asteroid moved at a speed of 24 km / s, while other newer asteroids, which were flown from the earth, a speed between 2.5 and 20 km / s had.

"It's been weak for a long time," Brown said of Asteroid 2019 OK. "After a week or two it'll be bright enough to spot it, but someone has to look in the right place, and as soon as it's finally recognized, things will happen quickly, but this thing is fast approaching, so we'll be there very soon Knowing the Flyby Of It. "

Last-minute recognition is yet another sign of how much over space is still unknown. A sobering reminder of the real threat that asteroids can pose, Duffy said.

"It should openly worry us all," he said. "It's not a Hollywood movie, it's a clear and present danger."

Duffy said astronomers have a nickname for the kind of space rock that came so close to Earth: "City Murderer Asteroids." If the asteroid the earth would have hit most of it would hit Earth Probably they hit the ground, causing devastating damage, Brown said.

"It would have been like a very large nuclear weapon," with enough power to destroy a city. "Many megatons, maybe in the 10 megaton TNT ballpark, so something you should not bother with."

In 2013, a much smaller meteorite with a diameter of about 22 meters broke above the Russian city of Chelyabinsk and dislodged one violent shockwave that collapsed roofs, shattered windows and left about 1,200 people injured The last space rock that hit the Earth as large as the asteroid 2019 OK was more than a century ago, Brown said. This asteroid, known as the Tunguska event, caused an explosion that filled nearly 500,000 square kilometers of forest land in Siberia.

Although the odds that a large asteroid lands in a city are "modest," Brown said it's still worthwhile spending resources on detection and prevention. According to Brown, Asteroid 2019 OK proves there are "still dangerous asteroids that we do not know can arrive unannounced on our doorsteps."

Scientists are working to develop at least two approaches to ward off potentially harmful asteroids Said Duffy, "One strategy is to slowly turn the asteroid away from its course and push it away from Earth," he said, the other he described as a "very elegant solution." If an asteroid is early enough According to NASA, it may be possible to redirect it using spacecraft gravity.

People should not try to "blow it up" with a nuclear weapon, Duffy said.

This makes for a great Hollywood movie. " , he said. "The challenge with a nuclear power plant is that it may work or not, but it would definitely make the asteroid radioactive."

Given Asteroid 2019 OK, Duffy emphasized the importance of investing in a "global dedicated approach" to asteroid detection because "sooner or later there will be one with our name, it's just a matter of when and if."

"We do not have to go the way of the dinosaurs," he said. "We actually have the technology to be sure of finding and distracting these smaller asteroids if we commit to doing so."

Emily Lakdawalla, chief editor of the Planetary Society, which promotes space exploration, said the recent near miss is a reminder that this is an important activity to observe the sky. "The more you can learn about an asteroid, the better people can be prepared to prevent potential disasters," she told the Post.

Nonetheless, Lakdawalla said the asteroid's close contact with the Earth may have caused concern Zero percent danger for us. "

" It's the kind of thing you learn something that you do not know anything about, like things that fly near you, and your tendency is to be scared, " she said. "But just like sharks in the ocean they really will not hurt you and they are really fascinating to look at."


Source link