An asteroid impact with Earth of Consequences

Geological studies conducted over the last decades have shown us that our planet has undergone a similar meteoric bombardment suffered by the Moon, and even more intense. In fact, due to its greater gravity, the impact rate on Earth is 1.5 times higher than our natural satellite. 

The size range of objects striking bodies is between a few meters to others of several kilometers across, and producing very different effects of different factors: the diameter of the shock, their speed, their density, the place to occur impact either on sea or land, etc.. An example of this was the "Tunguska Event" which little impact (June 30, 1908) has gone unnoticed, because it took place on a spot on the planet virtually underpopulated. What would have happened if the case occurred on an urban or densely populated area? 

 The impact of an asteroid or comet with a diameter of about 10 Km release about 100,000 megatons of energy, equivalent to over five million atomic bombs that destroyed Hiroshima or 100 times the current stockpile of nuclear weapons. The impact, which would produce a compression of 10000 GPA, would cause an earthquake measuring 12 on the Richter scale, winds over 500 km / h and a heating point of impact at about 100,000 ° C, temperatures capable of melting instantly between 10 and 100 times the mass of the projectile.

The impact of the meteorite into the sea would cause a mass of gas of 700 km in diameter

If the impact to take place over the ocean, the meteorite and a large body of water will become gaseous, generating a large plume of steam with a diameter of about 700 km, 50 times the thickness of the atmosphere. Total mass of water vapor and vaporized molten material between 10 and 100 times the meteor itself would ejected at high speed into the stratosphere and may reach a small percentage of the fragments to reach sufficient speed exhaust (11.2 km / s) and to escape the gravity of our planet. Soon all this steam reconstructed in rain and snow "dirty" due to mixing it with some solid material ejected, slow to return to the surface of our planet several weeks or months.

The violence of the impact would create a crater about 150 km in diameter with a central bulge caused by elastic rebound and produce mass movements on continental margins and turbidity at the base of the ocean. The collision in the ocean would result in a crater slightly larger and flatter than that produced on the mainland, due to the instability of the wall or edge of the crater under the ocean, with the possibility of rupture of the oceanic crust, which would leave mark morphology, gravitational and magnetic importance.

One of the immediate effects of this collision would be the emergence of huge tsunamis that sweep the Earth's oceans to beat against the shore. The initial tsunami height at the point of impact would be equal to the depth of the ocean. For example, a collision of a meteor of 10 km across at an ocean depth of 5 km form a tsunami height of 5 km would have decreased to initial "only" 150 meters after traveling halfway around the world in 27 hours. This huge wave violently all platforms erode external and flood inland areas. 

 The impact of an asteroid (diameter of about 10 km) would release about 100,000 megatons of energy, more than five million atomic bombs. Also results in an increase of heat energy in the atmosphere due to

direct heating by friction as the bullet passes through the air. Atmosphere explosion and disintegration of the object (or part thereof) in the air. Expansion explosive projectile and the rocks located at the site of impact after the collision. Movements of material ejected through the air and heating it.

After the impact would be a massive displacement of hot air and incandescent particles from the crash site, which would cause major fire for months in continental areas nearby, but could consume up to 20% of the global forest reserves.

The burning of vegetation would result in soot formation of pure carbon, which would blur the planet preventing the arrival of sunlight to the surface. For months or even years, the heat generated by the impact and the fall of the ejects from this produce a significant global warming (+10 ° C) and the Earth's surface, mainly in the areas closest to the place of Collision is estimated that the temperature could increase by more than 400 ° C in a radius of 5000 km and even more so in a radius of 1000 km. Explosive expansion of the projectile and rocks located at the site of impact after the collision. 

 After the initial heating suffered would be an opposite effect: the dust generated by the impact would be distributed by the Earth's atmosphere within a few days, causing what is called a nuclear winter, a period of several months of darkness and temperature drop Global planet. It is estimated that the total blockade of the radiation would last from days to weeks and that the phenomenon of darkness could persist between 3 and 6 months until sediments’ dust on the surface.

What implications would this?

A drastic reduction in atmospheric temperature, becoming inside this continents below the freezing point of water. Significant snowfall may occur up to 6 meters high on the continents, except for coastal areas, where the temperature is buffered by the oceanic water masses. The cooling oceans suffer so radical, because of its large heat capacity. Temperatures below freezing in much of the globe and significant snowfall could increase the Aledo of the Earth, which would imply a greater drop in temperature and initiate an ice age that would persist for an indefinite period. The collapse of photosynthesis and the breakdown of the food chain, which would cause mass extinctions of primary and secondary consumers, herbivores and carnivores, directly or indirectly dependent on terrestrial plants and phytoplankton. The reproduction of terrestrial animals would also be affected, they succumb from lack of food and unable to withstand adverse weather conditions. Alteration of phytoplankton photosynthesis would also entail the collapse of the marine food chain: in six months devour zooplankton to phytoplankton and then end up dying. 

Nuclear winter

 After this period of cold produce the opposite phenomenon: from the impact site is eyectarían by volatilization, and other toxic substances from the shocking (Ni, Cr, Co. ..), large amounts of H2O, CO2, SO2 and NOX, which would induce a greenhouse effect on earth and contaminate the entire surface thereof, causing acid rain (nitric and sulfuric acids) that acidification the sea surface and would cause mass extinction of plank tonic fauna. The heat produced by the greenhouse effect (+10 ° C) would not cease until the marine plankton and terrestrial flora volviesen to emerge, which could take between 10,000 and 30,000 years ago.