Aside from the explosion that it will cause, a massive asteroid can also trigger global effects that can alter Earth’s environmental and atmospheric conditions. This happened around 65 million years ago when an asteroid that was about 50 miles long crashed in a region that is now known as the Yucatán Peninsula in Mexico.
The explosion from the impact, which created a 93-mile-long crater, produced an energy equivalent to over 900 billion atomic bombs. Professor Stephen Hawking argued the laws of mathematics and physics mean an extinction-level asteroid impact is an unavoidable certainty.
According to Dr Maria UK, an astronomer at Cornell University in New York, localized asteroid impacts occur every few hundred years. Dr UK said: “A regional destruction happens at intervals on the order of 100,000 years, and devastates an area a size of a mid-sized country.
Asteroid warning: The late cosmologist feared the humanity needs to escape the planet in the future (Image: GETTY) Dr UK said the exact destructive potential of such an asteroid will depend on its composition and point of impact, but it would kill “billions” of people regardless.
Of that group, about 2,000 are considered “potentially hazardous,” meaning they have orbits within 4.5 million miles of Earth's and are big enough to cause massive devastation on impact. Congress has directed NASA to find and track at least 90 percent of the objects measuring 459 feet in diameter or larger and that pass within 30 million miles of Earth's orbit.
About 100 tons of dust and gravel-size particles enter the planet's atmosphere every day, burning up from friction as they crash through air molecules at more than 45,000 mph. Space rocks smaller than about 80 feet can create spectacular fireballs and generally cause little or no damage.
In 2013, an undetected 66-foot asteroid exploded 14 miles above Chelyabinsk, Russia, releasing 20 to 30 times more energy than the nuclear bomb dropped on Hiroshima. In 1908, a space rock estimated to be 160 to 260 feet wide exploded above an uninhabited part of Siberia, leveling 80 million trees and leaving hundreds of blackened reindeer carcasses across an area twice the size of Los Angeles.
The asteroid thought to have wiped out the dinosaurs 65 million years ago was even bigger, measuring 6 to 9 miles in diameter. It smashed into what is now the Gulf of Mexico, triggering massive tsunamis and sending up toxic plumes of sulfur.
By one estimate, it would take a nuclear weapon 4,000 times more powerful than the biggest nuke ever created to totally destroy an asteroid double the size of the one that killed the dinosaurs. A custom spacecraft would deliver the payload, but NASA won't be testing the concept anytime soon, because deploying nuclear weapons in space is both risky and banned by international law.
Another option is to use a spacecraft as a battering ram, a method NASA will experiment with in 2021 when it launches a probe against a nonthreatening asteroid. With only a few months' lead time, the best we could manage when faced with a “city killer” would be mass evacuations, a scenario NASA and FEMA already run drills for.
“These events are not rare; they happen,” NASA Administrator Jim Bridenstine told a Planetary Defense Conference earlier this year. Even on the small end, an asteroid of that size would destroy everything within hundreds of miles of ground zero, triggering massive earthquakes and fires.
The dust and smoke sent into the atmosphere would darken the skies for months, plunging the Earth into a mini ice age, causing worldwide crop failures. An asteroid similar in size to the one that doomed the dinosaurs would probably trigger mass extinctions, blot out the sun entirely for months, and kill billions of humans.
Still, some scientists think that those who didn't perish in the initial blast or die in the subsequent global famine might stand a chance at long-term survival. University of Colorado scientist Brian Too estimates that it would take an asteroid 60 miles wide to fully obliterate the human race.
You may have seen science fiction movies showing Earth being blasted by killer asteroids. The most recent killer asteroid hit Earth 66 million years ago, and was responsible for the dinosaur extinction.
Todd Slasher, executive director at Sloan Longways, says the dinosaur killing asteroid was six miles wide. Slasher says the asteroid likely caused hemispheric fires, burning of many forests, and tidal waves.
He says, “The soot and dust from such an explosion and the resulting fires would limit sunlight and cause a global cooldown, killing much of the plant life.' Mike Murray, astronomer and Delta College planetarium manager, says we would probably know about a space rock that big months or even years in advance.
Another theory is to attach a spacecraft to the asteroid, and nudge its course with a low thrust ion electric engine. Buddy Stark at Flint's Sloan Longways planetarium says slightly smaller asteroids should be of more concern.
Asteroids about 500 feet in diameter could wipe out a large city or a couple of counties. Many movies and books have portrayed this possibility (“Deep Impact,” “Armageddon,” “Lucifer's Hammer,” and so on).
There are obvious craters on Earth (and the moon) that show us a long history of large objects hitting the planet. It's thought that this asteroid threw so much moisture and dust in to the atmosphere that it cut off sunlight, lowering temperatures worldwide and causing the extinction of the dinosaurs.
NASA has tracked 90 percent of the near- Earth asteroids that are at least a half-mile wide and believes none of them has a significant chance of hitting Earth. An asteroid that big traveling at that speed has the energy roughly equal to a 1 million megaton bomb.
If the asteroid is as big as a 20-story building (200 feet on a side), it has an amount of energy equal to the largest nuclear bombs made today -- on the order of 25 to 50 megatons. In other words, if a mile-wide asteroid were to directly hit New York City, the force of the impact probably would completely flatten every single thing from Washington D.C. to Boston, and would cause extensive damage perhaps 1,000 miles out -- that's as far away as Chicago.
The amount of dust and debris thrown up into the atmosphere would block out the sun and cause most living things on the planet to perish. If an asteroid that big were to land in the ocean, it would cause massive tidal waves hundreds of feet high that would completely scrub the coastlines in the vicinity.
In other words, if an asteroid strikes Earth, it will be a really, awful day no matter how big it is. The asteroid was just discovered recently as space rock that is two miles wide and has caused a stir among the astronomers ever since.
Apparently, when close to Earth, its size may lead to large tidal waves, earthquakes, and general disastrous events and there's a possibility it may cause the planet carnage. The scientists have discovered that it may very well return and when it does, they fear that it will pass closer to earth and this may lead to a direct hit.
Moreover, he stated that there is little to no probability that a large object will strike the earth for the coming several hundred years. This was the result of scientists issuing a warning of possibilities of huge asteroids heading for Earth without the knowledge of the people.
When you're talking asteroids, it can be hard to visualize how News of different sizes would unleash such different levels of havoc on our vulnerable little planet. But this animation makes it easy to understand, with three simple examples showing how different kinds of space rocks would lead to three very different (but all bad) scenarios if they made landfall at the Big Apple.
Travelling at the same speed and with the density of rock, this bad boy would clean up, well… pretty much a fair chunk of the East Coast and let's just say Canada wouldn't be too happy either. US National Science and Technology Council released a study report On Thursday, June 21 which detailed the threats earth is facing due to gigantic space asteroids that hurtle across the universe.
Meanwhile, NASA has revealed that objects, which are large enough to destroy our civilization hit the earth once in every few million years, and they proposed three possible ways by which a dreaded collision can be avoided. Even though this method may seem something out of science fiction, many experts believe that the usage of a gravity tractor will fetch results when the size of the asteroid is not that gigantic.
If both the above-mentioned methods fail to work, the usage of nukes will emerge as the final option to deviate the asteroid from its collision course. A month ago, NASA detected the asteroid which burned up in South Africa just nine hours before its arrival.
Humanity has the skills and know-how to deflect a killer asteroid of virtually any size, as long as the incoming space rock is spotted with enough lead time, experts say. We'd likely have to slam multiple spacecraft into a gigantic asteroid over a period of several decades to do the job, but the high stakes would motivate such a strong and sustained response, researchers say.
Undiscovered asteroids Lu and four other spacewalkers spoke Oct. 25 at the American Museum of Natural History in New York City. A primary purpose of the event was to draw attention to the danger asteroids pose to human civilization and life on Earth, and to discuss ways to mitigate the threat.
That's enough lead time to mount a successful deflection effort, which would likely involve launching two separate space missions, former Apollo astronaut and B612 co-founder and Chairman Emeritus Rusty Schweickart told Space.com earlier this year. The second would follow up, launching a “gravity tractor” spacecraft to fly along with the space rock, nudging it further via a tiny but consistent gravitational tug.