How large does a meteoroid that hits the earth have to be to cause a global catastrophe?

Question

Approx. how often does this happen?

Answer 1

If a meteoroid is wider than 3 miles, there could be few chances the human being could survive.
It happens about every 80-100 millions of years.

Answer 2

That depends. Here's a neat little site for calculating the effect of meteor impacts:

http://www.lpl.arizona.edu/impacteffects/

If you are talking about the impact itself causing the catastrophe then it would have to be fairly large. But it depends on where the strike occurs: on land or in the ocean. A good sized ocean strike will not only cause tsunamis, but could cause a period of decreased temperature due to the increased albedo caused by water being thrown high into the atmosphere condensing and obscuring the sun. Large enough and it could trigger an ice age.

Strikes don't happen very often. There have been no major recorded land impacts for centuries, unless you count the Tunguska Event which was probably a comet which exploded in the air over Siberia in 1908. If that had hit in a populated region serious regional damage would have resulted.

The late Eugene Shoemaker of the U.S. Geological Survey came up with an estimate of the rate of Earth impacts, and suggested that an event about the size of the nuclear weapon that destroyed Hiroshima occurs about once a year. Such events would seem to be spectacularly obvious, but they generally go unnoticed for a number of reasons: the majority of the Earth's surface is covered by water; a good portion of the land surface is uninhabited; and the explosions generally occur at relatively high altitude, resulting in a huge flash and thunderclap but no real damage.

Answer 3

100 meters would be devastating to humanity. The global killer described above are for entire ecosystems. Humanity is much more frail than that. 800 million people live on the edge of starvation today. An impact of a rock just 100 meters in diameter wouldn´t be devastating to any ecosystem but it would throw up enough dust into the atmosphere, no matter where it hits, to cause cropa failures all over the world for years. So what do you think those 800 million people would do when they realize they are being pushed over the edge to extinction as their already scarce foodsupply dwindles? It would mean a global catastrophy to the socioeconomical system of earth (of humanity) if such an impact were to take place today.

Answer 4

The one that caused the dinos to die was about 6 miles across; I would guess around 5 miles and greater.

Fortunately, this doesn't happen very often, and as time continues, and the wandering rocks get pulled into other planets, the threat lessens. Perhaps every 100 to 150 million years...

Answer 5

Yep - 3 miles ish and above.

All depends on what the asteroid is made up of, how fast it is travelling and where it hits our earth.

This 'rare' event does happen, but as for a timescale - who knows.. I am sure one could not be predicted as they are not quite like buses!

I have heard something about the year 2018 although - a near miss of something!

Answer 6

First, to respond to your question, no. whether dinosaurs had no longer long gone extinct throughout the ok-T extinction (Cretaceous-Tertiary extinction), they might now no longer proceed to exist. maximum folk of "dinosaurs" have been chilly-blooded, and can as a result be no longer able to proceed to exist an ice age. despite the fact that, people might additionally no longer likely exist, because of the fact the niches unfold out with the aid of the extinction of the dinosaurs allowed for the speedy evolution and diversification of mammals, which as a result brought about the evolution of guy. Now, appropriate to the theory a meteorite impact brought about the extinction: in spite of the reality that, as a lot of people have already reported, that is basically a theory and not a reality, there is countless evidence that helps it. First is the crater itself. placed in Mexico, the Chicxulub Crater suits the age of the ok-T extinction, and is sufficiently vast to have brought about extensive harm to a extensive surrounding section. This impact might have additionally kicked particularly a lot of dirt into the ambience, blockading the sunlight for a minimum of 10 years. without direct photograph voltaic, flowers might start to die very at present. Herbivores might at present start up loss of life out from a loss of foodstuff supplies, and as a result carnivores might die besides. The Chicxulub Crater is partly on land and partly over the sea. a extensive impact over water might have additionally brought about super tsunamis, inflicting harm to all surounding coastlines (there is likewise geologic evidence of this comparable to the ok-T extinction).

Answer 7

Interestingly enough, numerous small stones (meteor bits?!) showered down on various parts of Europe not too long ago. Though no one was killed, it did damage to property. So, I guess one could say not only size matters, but quantity.

Answer 8

Maybe about 10 miles wide.

Maybe once every 100 million years.

Maybe.

Answer 9

3 miles and up

Answer 10

it depends on the makeup of the Meteorite, the speed it is traveling, and the angle it hits the atmosphere.





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