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Will an Asteroid Strike Planet Earth?

Kelley has great interest in astronomical matters and pays very close attention to asteroids that could impact planet Earth.

Barringer Meteor Crater

Barringer Meteor Crater

Astronomers watch for rocks that could collide with the Earth

Do you like living dangerously? Well, you don't have much choice. In the game of cosmic billiards, the cue ball is headed our way - sooner or later!

It’s been theorized that an asteroid only a half-mile in diameter could destroy civilization on Earth, and hundreds of such rocks are out there in space, many of them crossing the Earth’s orbit, perhaps right this minute.

In June 2011, a bus-sized chunk of real estate missed the Earth by only 7,500 miles. If this asteroid had hit the Earth, it would have blown a sizable crater in the ground, perhaps injuring or killing some hapless folks as well. And earlier in 2011, a somewhat smaller asteroid missed the Earth by only 3,400 miles!

Are you nervous yet? You should be. Everybody should. If a big enough rock hit the Earth, the climate could be disrupted so severely that plants wouldn’t grow for years or even decades. Now there’s food for thought!

Now let’s look further into the subject of asteroids colliding with the Earth and see if there’s something we can do about this potentially devastating possibility. Please read on.

Asteroids of the inner Solar System

Asteroids of the inner Solar System

Types of Asteroids

There are three types of asteroids. Main Belt Asteroids are the ones revolving around the Sun between the orbits of Mars and Jupiter. Theory has it these asteroids – millions of them, in fact - are the remnants of a protoplanetary disk that didn’t quite come together as a planet. The largest such asteroid is Ceres, which is about 600 miles in diameter and considered a dwarf planet like Pluto. The second largest asteroid in the Belt is Vesta.

Trojan Asteroids follow planets around but rarely collide with them. The most common Trojans are the ones that follow Jupiter. There may be millions of these types of asteroids as well.

Near-Earth Asteroids (or NEA’s) are the ones we should worry about. These potential killers have orbits that take them near the earth; some even cross the orbit of the planet. These are known as Earth-crossers. As of 2010, over 7,000 NEA’s are known to exist, and as many as 1,000 of them could be as much as a kilometer (.62 miles) in diameter.

Any one of these NEA’s could have the Earth’s name on it. Of course, the ones we don’t even know about may pose a much deadlier risk!

Chicxulub Crater

Chicxulub Crater

Barringer Meteor Crater in Arizona

Barringer Meteor Crater in Arizona

Comet Shoemaker-Levy 9

Comet Shoemaker-Levy 9

Aftermath of the Tunguska Event

Aftermath of the Tunguska Event

The Dinosaur Killer Asteroid and Others

About 65 million years ago an asteroid stuck the Earth that may have brought about the extinction of the dinosaurs. (Some scientists think continental drift snuffed the dinos, but that’s the subject of another article.) Scientists may have spotted the resultant hole in the ground, the so-called Chicxulub Crater just north of the Yucatan Peninsula in Mexico.

It’s been estimated that this immense asteroid was six to 10 miles in diameter, roughly the size of Mt. Everest. When it landed in the ocean, it caused mega-tsunamis thousands of meters high. (Try to imagine this scene.) If an asteroid this size struck the Earth today, it could possibly wipe out the entire human species!

Meteor Crater in Arizona

If you want to see what happens when an asteroid hits the Earth, then take a look at Barringer Meteor Crater in Arizona. (An asteroid becomes a meteor as it burns white hot in the atmosphere.) About 50,000 years ago, an asteroid struck the earth, leaving this crater, which is about 4,000 feet in diameter and 150 feet deep. Made of nickel and iron, the asteroid that blasted out this hole in the ground was about 50 meters (54 yards) across. The energy of the impact has been estimated at 10 megatons. You wouldn’t have wanted to be within a 100 miles of this hot spot!

Comet Shoemaker-Levy 9

In July 1994, people discovered what happens when an asteroid slams into a planet. Comet Shoemaker-Levy 9 was actually a comet, which is simply an asteroid with ice on it. As the comet orbited the planet Jupiter, it broke into smaller parts, all of which eventually fell into the planet, releasing incredible amounts of kinetic energy. The largest chunk, fragment G (about a mile across), struck Jupiter with the equivalent force of 6 million megatons of TNT, 600 times the world’s nuclear arsenal, the impact creating a dark cloud the size of the Earth!

As an aside, it’s a good thing Jupiter is out there “vacuuming up” comets and asteroids before they have a chance to the hit the earth; otherwise, life may not have gotten a foothold on this planet because of the nearly constant bombardment over millions of years!

Tunguska Event

Nobody knows for sure what it was, but an object from space exploded over the Tunguska region in Siberia in June 1908. Most experts believe it was a rocky asteroid or comet, about 90 yards across, which detonated some 5 miles above the surface of the Earth, the explosion flattening over 800 square miles of pine forest. If the Tunguska Event had happened over one of Earth’s mega cities, it would be similar to a 30-megaton nuclear bomb exploding in the air, likely incinerating millions of people within seconds!

Co-founder of Comet Shoemaker-Levy 9, Eugene Shoemaker estimated that a Tunguska-like event occurs on earth about every 300 years.


Out in space is an asteroid that may have Earth in its crosshairs. Apophis, an 800-foot chunk of rock (much larger than the Tunguska impactor), will approach the earth in 2029; and if it passes through what’s called a gravitational keyhole, then it could strike the Earth in 2036. However, the odds are very small that it will ever collide with our planet – about one in 250,000. At any rate, such an asteroid probably wouldn’t end civilization, but it could destroy any city on Earth!

But some Russian scientists caution that even if Apophis misses the Earth in 2029 or 2036, as it swings by the Earth, it could break into many smaller parts, any one or more of which could strike the planet.

According to Neil DeGrasse Tyson’ book Death by Black Hole, if Apophis hits the Earth, it will plunge into the Pacific Ocean between California and Hawaii. “The tsunami it creates,” the book reads, “will wipe out the entire west coast of North America, bury Hawaii, and devastate all the land masses of the Pacific Rim.”

In 2020, David Tholen, an astronomer at the University of Hawaii, said Apophis will definitely not hit the Earth in 2029 or 2036, but could still collide with the Earth in 2068, because up to this point the Yarkovsky effect has not been taken into account. The Yarkovsky effect predicts that as the sun’s rays hit one side of the asteroid, the resultant heat radiating away will alter the rock’s course by 170 meters per year, thereby pushing it closer to Earth. Scientists will learn more about the path of Apophis when it swings close to Earth in 2029.

Other NEA’s

Asteroid 2011 CQ1, which missed the Earth by only 3,400 miles in early 2011, could strike the Earth when it returns in 2022. This is not a big asteroid, but Asteroid 2005 YU55, a 1,300-foot monster, passed within 200,000 miles of the Earth on November 8, 2011. If it had hit the Earth, it would have blasted a crater more than four times the size of Barringer Meteor Crater in Arizona. Whew! That was a close one!

Asteroids Ida (left) and Dactyl

Asteroids Ida (left) and Dactyl

Asteroids in Recent Times

On February 15, 2013, asteroid 2012 DA14, swung within 17,200 miles of Earth, close enough to collide with a communications satellite. This asteroid is no pebble in the sky. Measured at about 160 feet across, it’s the approximate size of the asteroid that exploded over the Tunguska region of Russia in 1908; it’s also about the same size as the asteroid that created Barringer Meteor Crater in Arizona.

Astonishingly, on the same day, a large meteor streaked across the sky in central Russia!

As reported on “Meteor Strike,” an episode of the TV program Nova, first shown on March 27, 2013, the meteor approached the Earth at a shallow angle and exploded high in the atmosphere, injuring about 300 people. If this meteor - actually an asteroid about 65 feet across - would have plunged to Earth at a steeper angle, it could have exploded much closer to the surface or hit the ground, perhaps killing hundreds if not thousands of people. The people of Russia are fortunate indeed!

On April 14, 2017, an asteroid labeled JO25, nicknamed “The Rock” and about the size of the Rock of Gibraltar, missed Earth by about 1.1 million miles. This meteoroid is about 2,000 feet long and if it had hit the Earth it may have ended civilization for the next hundred years or so. But, scientists said, the odds of this object actually hitting the Earth were only one in a million. Hey, if people had these odds of winning, they’d buy more lottery tickets!

A so-called lost asteroid, because it was discovered in 2010 and subsequently lost by scientists, whizzed past the Earth on May 15, 2018. Labeled 2010 WC9, this meteoroid missed our planet by just 126,000 miles. At 130 meters long, or about the size of the Great Pyramid at Giza, this space rock could wipe out any city on Earth and is about six times larger than the meteor that exploded over Russia in 2013. Let’s hope scientists or any other observers never again lose sight of this city-buster!

Artist's depiction of Oumuamua

Artist's depiction of Oumuamua

Interstellar Asteroids Could Be a Threat to Earth

Most asteroids we have to worry about come from inside the solar system, but one came from the vastness of interstellar space. Some people wondered if it was a comet or a spacecraft from another star system. Discovered in October 2017 and given the name Oumuamua, which means in Hawaiian “first scout from a distant place,” this space rock is cigar-shaped and about 100 meters wide by 1,000 meters long. Fortunately, there’s no danger of it hitting Earth or any other body in the solar system, as it seems to be tumbling its way on a hyperbolic trajectory through the solar system, while on its way back into the interstellar medium.

But many other such rocky interstellar visitors could be headed our way. A meteor that burned up in Earth’s atmosphere over the northeastern coast of Papua New Guinea in January 2014 has now been labeled as another one of these interstellar interlopers. These two events make a person wonder: How many more of these visitors from the cosmos are out there? And could any of them collide with the Earth?

Could Oumuamua Be a Spacecraft Created by Aliens?

As written in his book, Extraterrestrial: The First Sign of Intelligent Life Beyond Earth (2021), Harvard University astrophysicist Abraham “Avi” Loeb thinks Oumuamua is almost certainly a product of extraterrestrial intelligence. According to a vast amount of compelling scientific evidence obtained since 2017, this cigar or disc-shaped celestial interloper could be a spacecraft energized by a laser-driven lightsail, the technology for which now exists on Earth.

But at present, at least, most scientists continue to think that Oumuamua is just an asteroid or comet tumbling through space with no particular place to go and no reason for its existence. Loeb conjectures that the object could be a space buoy designed to watch out for the approach of other space-bound civilizations.

Meteor trace over Chelyabinsk, Russia in 2013

Meteor trace over Chelyabinsk, Russia in 2013

What Can We Do?

Just about any scientist will tell you that it’s only a matter of time before the Earth is struck by an asteroid large enough to cause massive damage and loss of life. What can we do about such an eventuality? Not much. But keep in the mind that there are many agencies that watch for asteroids. Chances are any asteroid miles across will be spotted months if not years before it can strike the Earth, which would give agencies such as NASA and the U.S. military plenty of time to change the trajectory of the asteroid or destroy it.

Regarding such matters, in March 2015, the United Nations created two new organizations: the Space Mission Planning and Advisory Group (SMPAG) and the International Asteroid Warning Network (IAWN), both of which dedicated to protecting the Earth from an asteroid strike or at least mitigate the damage if one strikes the planet.

But when NEA’s hundreds of feet across come around, there may be little warning. Just hope you’re not in the path of this lethal thing from space. Yet it will hit somewhere, and the most likely worldwide result will be a reduction in food production due to the massive amount of debris blown into the atmosphere. This sunlight blocking scenario would make food prices skyrocket. So, if possible, be prepared for that, however you can.

Please leave a comment.

Meteor explosion in Russia in 2013

© 2011 Kelley Marks


Tlaapi on June 30, 2019:

Asteroids are new to me I never know our planet was under such a threat

meteor on January 14, 2018:

honestly, I would like to see an asteroid impact earth

Kelley Marks (author) from Sacramento, California on December 10, 2013:

Thanks for the comment, Lybrah. Let's hope God is watching out for the earth and its people; otherwise, we will be hit sooner or Later. Bye!

Lybrah on December 09, 2013:

Very interesting hub. Who knows if God would allow an asteroid to hit the earth? It's scary how close some of them come.

Kelley Marks (author) from Sacramento, California on October 09, 2013:

Thanks for the comment, Stuff4Kids. You seem to know a lot about asteroids, striking the earth and otherwise. At any rate, those rocks in the sky certainly helped form what is now our wonderful blue orb in space. Later!

Amanda Littlejohn on October 09, 2013:

Wow, you sure know your stuff.

I think I do favor the idea that a meteor strike was responsible for the atmospheric and climatic changes that wiped out the dinosaurs. As to the use of technology to protect ourselves from a future collision, well - yes, of course!

As far as I understand it our own little blue dot was formed from the debris of an exploded star which eventually coalesced into planetary spheres around the gravitational pull of the Sun. But yes, there sure is a lot of stuff still whizzing around out there and you do a great job of explaining it all.



Kosmo, you have almost 1000 followers and yet a simple guy who likes comment of a novice here! You are right, science has no morality or emotions!

Kelley Marks (author) from Sacramento, California on October 22, 2012:

Thanks for the comment, psbhatt. You're right; comets and asteroids have brought much to planet earth, especially life-giving water. Hey, with science, there is no morality. Later!


kosmo, your article is "awesome" but you omitted to mention that it is asteroids and comets that brought water and life to earth! I like your article, just brilliant!

sharewhatuknow from Western Washington on September 03, 2012:

Yes of course... if our technology could deflect massive meteor strikes, I am all for it.

Who wouldn't be? Hands?


Kelley Marks (author) from Sacramento, California on September 02, 2012:

Thanks for the comment, sharewhatuknow. I agree that it certainly doesn't help to dwell on the possibility of an asteroid striking the earth, but being prepared to deflect one wouldn't be a bad idea. Later!

sharewhatuknow from Western Washington on August 31, 2012:

Very good hub Kosmos. Like others, I try not to dwell on meteor stikes that could wipe out life on earth, too sad and harsh. But I suppose it would be a very quick demise, and that is how most of us would like to go. After all, we all go sooner or later anyway, threatening meteors or not.

I voted up.

Kelley Marks (author) from Sacramento, California on July 19, 2012:

Thanks for the comment, James Peters. I also like this article a lot - it's a combination of astronomy and Doom's Day, making for a sensational story. Later!

James Timothy Peters from Hammond, Indiana on July 19, 2012:

This was an awesome article! I really enjoyed it.

This article blew mine out of the water...oh well (LoL).

I wrote something similar to the subject...

Thanks a lot.

Keep writing - Write on!

Kelley Marks (author) from Sacramento, California on June 23, 2012:

Science isn't morbid, Lalo. It simply is. Later!

Lalo on June 23, 2012:

Why So Morbid

Kelley Marks (author) from Sacramento, California on May 23, 2012:

Thanks for the comment, Dr. Billy Kidd. I'm not squeamish about asteroid strikes - let's simply be prepared - just in case. Hey!

As for you Randy Godwin, we do seem to get hit with a sizable object every 100 to 300 years. The next one could come in 100 years or next week. Later!

Randy Godwin from Southern Georgia on May 22, 2012:

Who knows? The earth averages a strike by a meteor, asteroid, or comet on the average of every 100 years. The last strike, of course, was the Tunguska event in 1908. You do the math! LOL!


Dr Billy Kidd from Sydney, Australia on May 22, 2012:

Planet Earth has lasted 4 billion years. Let's not get squimish about it going out any time soon.

Kelley Marks (author) from Sacramento, California on December 23, 2011:

Thanks for the comment, Randy Godwin. I don't think the strike of an asteroid caused megafauna to go extinct 10,000 years ago, but it's a very interesting theory nonetheless. Later!

Randy Godwin from Southern Georgia on December 23, 2011:

Yep, we are indeed overdue for a hit, Kosmo! Some think the megafauna and Clovis culture may have been destroyed by some type of explosion over the Americas which caused widespread wildfires wiping out many of the huge animals and the predators which fed on them.

A fascinating subject which will no doubt be added to in the future. Good read!

Kelley Marks (author) from Sacramento, California on December 23, 2011:

Thanks for the comment, Cyndi10. Yes, I'm very glad YU55 didn't hit the earth. That big rock could have caused a catastrophe. Later!

Cynthia B Turner from Georgia on December 23, 2011:

Hello, Great article. I also believe it's a matter of when. I'm glad that YU55 was not the one, although I believe it was close. Thanks for sharing so much info.

kayla on October 01, 2011:

good website 2 look @ and if you are frightened by it u should be. if an asteroid does hit earth RUN 4 YOUR LIFE! your other choice is 2 die and you will not have a life anymore your life not mine guys 4 your own good mate

Kelley Marks (author) from Sacramento, California on September 27, 2011:

Thanks for the comment and edifying data, Paul Felix Schott. I wrote about asteroid 2005 YU55 in my article. Hold onto your hats, folks, this could be a close call. Later! (I hope.)

Paul Felix Schott on September 27, 2011:

This will be a very close call i pray it is only that. Discovered on December 28, 2005 by Robert McMillan of the Spacewatch Program A potentially hazardous Asteroid known as 2005 YU55. This Asteroid some what Large 400 meter-sized type – C, will pass by the Earth right between our moon and Earth. On November 8, 2011.

The people on Earth have not seen an Asteroid of this size in advance. One this big Has not impacted Earth in over at least 4 thousand years. Most Objects that have a diameters over 45 meters or 147.637 ft strike the Earth approximately once every thousand years or so. Lying flat everything for hundreds of miles. Like the TUNGUSKA 1908 SIBERIA, RUSSIA CRASH OR Tunguska Explosion. This one did not even hit the Earth with its full Impact, it burst high in the air above the ground plowing it apart into many smaller parts. Making thousands of very deep holes in the Russian forests. Many of them in dense forest far from any roads or towns.

One 400 Meters 1,312.3 ft in diameter like this one YU55 weighing millions of tons would if impacted Earth on land would darken all of the Earth not for just days but much longer. It would change the weather not seen on Earth in over thousands of years a massive climate change to say the least.

The World and NASA will watch this one very closely.

The Lord’s Little Helper

Paul Felix Schott

Kelley Marks (author) from Sacramento, California on September 22, 2011:

Yes, emin3nt, let's hope the big rock doesn't fall on us any time soon. Later!

emin3nt from Madrid on September 22, 2011:

anything is possible,i hope will not hit sooooooooooooon

Kelley Marks (author) from Sacramento, California on September 21, 2011:

Hey, seocoursemumbai, I haven't heard of China's program for deflecting asteroids. I'll have to watch for it. Thanks for the comment. Later!

seocoursemumbai from Mumbai ( India) on September 21, 2011:

The has certainly to come and that would be Armageddon. There's a possibility of an asteroid hitting the earth's surface. There's some news around that china has already started working on a way to blast off the asteroid in the atmosphere it self.

Kelley Marks (author) from Sacramento, California on September 03, 2011:

Thanks for the comment, HomerMCho. Don't let the rock fall on your head. Later!

HomerMCho on September 03, 2011:

It's an interesting hub!Like it.

Nell Rose from England on August 06, 2011:

Hi, fascinating stuff, my brother has always said this is the way the Earth will end, seems he was telling the truth! lol cheers nell

Kelley Marks (author) from Sacramento, California on July 13, 2011:

Thanks for the comment, Cogerson. Yes, we do have Bruce Willis and Robert Duvall, but wouldn't Captain America do a better job? Superman is better equiped as well. Later!

UltimateMovieRankings from Virginia on July 13, 2011:

Very nicely is a good thing that the earth has Bruce Willis and Robert Duvall to save the pretty scary stuff. I found your hub both interesting and informative....voted up and useful.

Kelley Marks (author) from Sacramento, California on July 07, 2011:

The U.S. should have the means for dealing with asteroids. Retiring the space shuttle may not have been such a good idea. At any rate, let's hope we have more than hours to prepare . . . ! Later!

Kelly Umphenour from St. Louis, MO on July 06, 2011:

It is a scary threat Kosmo - I think it's bound to happen eventually. Hopefully we will have enough warning to prepare!

sreekumar sukumaran on July 06, 2011:

Agree with PETER LUMETTA may be it may induce rich to contribute more for saving earth and finally themselves. lol.

Kelley Marks (author) from Sacramento, California on July 06, 2011:

Thanks very much for the comments, everyone! I agree that we're certainly overdue for another asteroid strike, though it may not happen for decades or centuries. I also agree with Immartin that it doesn't do much good to worry about such dire possibilities, when we have no control over it. However, it may not hurt to stockpile some food. At the very least, you could sell it for a profit in the coming years. Later!

lmmartin from Alberta and Florida on July 06, 2011:

Very interesting, but I admit that I do not spend time worrying or being nervous over things beyond my control -- like asteroid collisions and economic collapses. Why waste the energy? Not like I'll be spared no matter how much I fret over it, so let's just say que sera.

Randy Godwin from Southern Georgia on July 06, 2011:

We average 1 major asteroid or meteor impact roughly every 100 years with the last being the Tunguska event. We are overdue for another any time now. The "sky is falling" may not be too far off! LOL!


Carolee Samuda from Jamaica on July 06, 2011:

You trying to scare us Kosmo?

Well I don't know much about these things, but it is apparent it has happened before. I don't want it to happen again. If it does it might be devastation. I guess we just have to wait and see, not sure what mankind can do about it.

PETER LUMETTA from KENAI, ALAKSA on July 05, 2011:

Kosmo, a scary but real threat to our planet. Some common threat like this might even get the attention of the rest of the world and cause us to get along for a while. Maybe even get the rich folks to pay some of the taxes needed to fund a project to save the planet. In any event our cosmic Karma will be played out sooner or later. Thanks Kosmo, Peter

Christopher Wanamaker from Arizona on July 05, 2011:

Its not a question of If, but When. As you've shown here, its happen many times before. I guarantee it will happen again. What are we going to to do about it? Not sure. Great Hub that got me thinking...