A massive asteroid hurtled past Earth Friday. The fly-by object did not pose any risk of striking Earth.
The nearly two-mile wide asteroid named 1998 QE2 whirled past the Earth at around 5 p.m. in America’s Eastern Time zone. It was 3.5 miles away from the Earth. The distance is roughly 15 times further from the moon, Earth nearest neighbor.
However, by the standards of astrophysics its mere 3.5 million miles distance from the Earth qualifies as a relatively close approach. Scientists are constantly on the alert on these rogue rocks, because of their potential to cause massive devastation if they hit the Earth.
Early this year in February, asteroid 2012 DA14, which was noticed a year ago, came close to earth. It whirled the earth by a meager 17,200 miles. As large as the size of a football field, it barely missed hitting the Earth. In fact, it came closer that than many communications satellites circling the Earth. This marked the closest approach of such a large asteroid that astronomers have even known.
On the same day in Russia, a smaller, unrelated asteroid exploded 12 to 15 miles above the country’s Chelyabinsk region, which is about 930 miles east of Moscow. It broke into pieces in mid air. The blast caused widespread panic. The shock waves from the blast damaged hundreds of buildings and injured more than 1,000 people, according to media reports. A local zinc factory collapsed.
Many reported witnessing a bright flash and numerous explosions.
“At first I saw a huge bright fire up in the skies, and then came a loud explosion that not only shattered the windows, but blew out the window frames,” Taisiya Alabuzhina told reporters.
“My heart is still beating 200 heartbeats a minute! … I saw this terrible flash, it was red-orange! My eyes are still hurting,” a witness from Chelyabinsk wrote on a local web forum. “I turned off all the lights, sat the kids on a couch and waited… Oh, my God, I thought the war had begun.”
Scientists think the explosion was caused by an asteroid that was about 50 feet wide and weighed about 7,000 tons before it hit Earth’s atmosphere.
The giant asteroid or comet that struck just of the coast of Yucatan Peninsula some 65 million years ago has been estimated at six miles across. It traveled faster than a jetliner and created a 110-mile-wide crater. Scientists maintain that dinosaur extinction happened because of this event. Also this massive blast changed the Earth was changed forever.
Scientist conclude that after this episode, dark clouds of dust blocked the sun, darkened, and chilled the earth to dangerous levels and further caused the extinction of plants and animals living at that time.
The events in Russia in February triggered debate about the threat our civilization faces from asteroids.
“An asteroid that size, a kilometer or bigger, could plausibly end civilization,” John Holdren, a White House science adviser, told legislators at a US House of Representatives Science Committee hearing in May.
However, according to Holdren, only about 10 percent of an estimated 10,000 potential “city-killer” asteroids, those with a diameter of about 50 meters, have been found.
These episodes highlight the challenges astronomers face in predicting such space objects. Astronomers have classified about 95 percent of the space objects wider than half a mile – those that could destroy civilization.
Astronomers assess that an asteroid the size of 2012 DA14, which came within a cosmic hair’s breadth of our planet on Friday, strikes the Earth approximately once every 1,200 years.
By Perviz Walji
Sources: Christian Science Monitor, Science Recorder, RT