how would an asteroid exterminate all life forms on earth?

Question

if a large enough asteroid struck earth how would everyone be killed? could people in a bunker or bomb shelter be live? How long before humans could come out of the bunkers? could life survive on earth?

Answer 1

yes, people can survive the blast if in a bomb shelter, but the outside won't be habitable for many many years after so they would have to stay down there for a long time.

Answer 2

It would be a mass extinction event. Its happened before.

The impact of a sufficiently large asteroid or comet could have caused food chains to collapse both on land and at sea by producing dust and particulate aerosols and thus inhibiting photosynthesis. If it hit sulfur-rich rocks, it could also have emitted sulfur oxides which were precipitated as acid rain and poisoned many organisms — contributing further to the collapse of food chains. Some scientists have suggested that impacts could also have caused megatsunamis and / or global forest fires, but these ideas are now regarded as exaggerations.
Only the end-Cretaceous extinction is associated with strong evidence of such an impact, but that impact is easily the largest for which there is strong evidence.

The problem involves the atmosphere being filled with dust and debris from the impact creating a deep winter effect killing almost all plant and animal life on earth. Scientific research suggests this condition will exist for 2 or more years depending on the severity of the event.

Since the sun's energy will be mostly blocked out we will be in a deep freeze condition on the surface making higher life impossible.

Yes, people could live if they are not under the impact site and have sufficient provisions to sustain themselves until the dust filled atmosphere finally clears. However they will surface to a dead and desolate planet with little life and facing a serious struggle to survive until the Eco-system recovers.

Answer 3

Well, it'd be fun.

The object would hit the surface, causing debris from both the asteroid and the Earth, in the form of molten rock to be shot out into space (Remember this debris, it's important later).

This causes a shock-wave of heated air (heated air expands, generally away from the blast). There may even be a tsunami for added fun.

The debris from earlier? Now it starts to fall back to Earth. It re-enters the atmosphere, heating the gasses in our atmosphere. This causes global surface temperatures to rise to over 500 degrees F.

Debris from the impact creates global cloud cover that would suffocate most life, as it wouldn't allow for photosynthesis to occur.

How long you will need to remain in a bunker depends on how close you are to the impact site. If you're AT the impact site, you'll be permanantly etched into the bunker, so to speak. If you're a few thousand kilometres away, you'll need to wait for the ground to cool off a few weeks. Several thousand kilometres away, you'll be able to come out rather soon. All you need to do is wait for the heat to die down.

This all assumes an average-sized asteroid, a few kilometres across. If something 500+ kilometres hit, we're all screwed.

Answer 4

A large asteroid would throw so much dust into the atmosphere that green algae and plants (the base of the food chain) couldn't get enough sunlight. The dust would spread around the entire globe within a few months. Once the algae and plants die, everything that eats them will die, too.

We're talking about 100% crop failure, with billions dying of starvation, and probably killing the ones who are able to produce food by artificial means (such as hydroponics). Society would collapse completely.

It might wind up that a protected military base such as NORAD could become self-sufficient, living off a nuclear reactor and eating hydroponic crops. They might last long enough for the dust to settle, then they could re-colonize the Earth.

You could expect about 95% of all species on Earth to die, though.

Answer 5

Everyone would be killed by the clouds suspended in the air, caused by the impact of the asteroid, it will cause a lot of ice in the world surface.
Humans in refugees could come out of bunkers after the clouds disappear from the sky.

Answer 6

Well, basically what would happen is that a large enough impact would set off EQs and volcanoes all over the world. All that volcanic ash would cloud the sky and block the sun. No sun, no plants. No plants, no herbivores, no herbivores, no predators (including us). Death wouldn't be instantaneous (except those hit by the impactor or tsunamis, or falling buildings from EQs), but the volcanic dust would stay up there for quite while.

I don't think bunkers would help with all the earthquakes happening and even if the did clean water and food would be at a premium for those surviving.

Answer 7

Depends, since most of earth is water,
1st- mass flooding
2nd - make earth's orbit off-track either making closer to the sun or farther away, both which is no good
3rd- possibilities are very slim that an asteroid would exterminate all life forms as you would have to think about micro-organisms that survive in the most extreme environments of earth.

Answer 8

If it were big enough it would set the atmosphere on fire and liquefy the earth crust several hundred feet down. People in bunkers would not emerge. I suppose the lifeforms evolved around those undersea vents would survive....
Even a medium one would devastate the continent it landed on, fires, quakes, ash....
And if it landed in the ocean the waves it generates and the damage done by the temperature increase and water displacement would be detrimental.

Smaller ones would allow some life, smaller yet...and so on.

Answer 9

If a large enough asteroid struck the earth and caused huge amounts of particulate matter to be spewed into the atmosphere, blocking sunlight, plant life could not flourish and they and the many forms of life that depend on green plants would die.

Answer 10

Depending on the size, one big enough can cause another ice age. For example, if a large asteroid hit it would cause the sun to be completely blacked out for three years or more. It can also cause floods and earthquakes, then global freezing occurs. END of all life........ Earth will become another Europa for five hundred more years.

Answer 11

If a very large asteroid hit the Earth, it'd completely destroy the Earth. If the Earth was destroyed, do you think any humans will be alive?