How big an asteroid will it take to destroy the United States?

I am doing some research and i would like to know how big an asteroid would it take to destroy the United states? Include the size of collision, amount of released energy etc.

Update:

Well it dosen't have to destroy it on impact, but could also create enough dust to block out sunlight in the whole United states and block out light. Note: the answer maybe phrased incorrectly, add any extra details if you can

Update 2:

Also include speed

11 Answers

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  • 1 decade ago
    Favorite Answer

    Impact Effects

    Please note: the results below are estimates based on current (limited) understanding of the impact process and come with large uncertainties; they should be used with caution, particularly in the case of peculiar input parameters. All values are given to three significant figures but this does not reflect the precision of the estimate.

    Assumption: You're on the west coast and the 6 mile in diameter astroid impacts the eastern seaboard. Not only would there be significant physical damage throughout the US, we would be economically untenable.

    Distance from Impact: 3542.00 km = 2199.58 miles

    Projectile Diameter: 9656.04 m = 31671.81 ft = 6.00 miles

    Projectile Density: 3000 kg/m3

    Impact Velocity: 72.00 km/s = 44.71 miles/s

    Impact Angle: 45 degrees

    Target Density: 2500 kg/m3

    Target Type: Sedimentary Rock

    Energy:

    Energy before atmospheric entry: 3.67 x 1024 Joules = 8.76 x 108 MegaTons TNT

    The average interval between impacts of this size somewhere on Earth during the last 4 billion years is 8.5 x 108years

    Major Global Changes:

    The Earth is not strongly disturbed by the impact and loses negligible mass.

    The impact does not make a noticeable change in the Earth's rotation period or the tilt of its axis.

    The impact does not shift the Earth's orbit noticeably.

    Crater Dimensions:

    What does this mean?

    Transient Crater Diameter: 117 km = 72.7 miles

    Transient Crater Depth: 41.4 km = 25.7 miles

    Final Crater Diameter: 219 km = 136 miles

    Final Crater Depth: 1.5 km = 0.93 miles

    The crater formed is a complex crater.

    The volume of the target melted or vaporized is 23000 km3 = 5530 miles3

    Roughly half the melt remains in the crater , where its average thickness is 2.14 km = 1.33 miles

    Thermal Radiation:

    What does this mean?

    The fireball is below the horizon. There is no direct thermal radiation.

    Seismic Effects:

    What does this mean?

    The major seismic shaking will arrive at approximately 708 seconds.

    Richter Scale Magnitude: 10.6 (This is greater than any earthquake in recorded history)

    Mercalli Scale Intensity at a distance of 3542 km:

    IV. Felt indoors by many, outdoors by few during the day. At night, some awakened. Dishes, windows, doors disturbed; walls make cracking sound. Sensation like heavy truck striking building. Standing motor cars rocked noticeably.

    V. Felt by nearly everyone; many awakened. Some dishes, windows broken. Unstable objects overturned. Pendulum clocks may stop.

    Ejecta:

    What does this mean?

    The ejecta will arrive approximately 1160 seconds after the impact.

    Average Ejecta Thickness: 3.77 cm = 1.48 inches

    Mean Fragment Diameter: 119 micrometers = 4.67 1/1000 of an inch

    Air Blast:

    What does this mean?

    The air blast will arrive at approximately 10700 seconds.

    Peak Overpressure: 46700 Pa = 0.467 bars = 6.64 psi

    Max wind velocity: 93.1 m/s = 208 mph

    Sound Intensity: 93 dB (May cause ear pain)

    Damage Description:

    Multistory wall-bearing buildings will collapse.

    Wood frame buildings will almost completely collapse.

    Glass windows will shatter.

    Up to 90 percent of trees blown down; remainder stripped of branches and leaves.

  • 3 years ago

    Apophis ( /??p?f?s/, in the previous generally happening via its provisional designation 2004 MN4) is an intensive to-Earth asteroid that led to a short era of shock in December 2004 through fact preliminary observations indicated a small probability (as much as two.7%) that it might strike the Earth in 2029. further observations presented better predictions that eradicated the potential of an impact in the international or the Moon in 2029. even though, a threat remained that interior the 2029 close bump into with Earth, Apophis would bypass via a gravitational keyhole, an exact area in area no considered one of those one million/2-mile extensive,[6] that would set up a destiny impact on April thirteen, 2036. This threat saved the asteroid at point one million on the Torino impact probability scale till August 2006, while the probability that Apophis will bypass for the duration of the keyhole grow to be desperate to be very small. Apophis broke the checklist for the optimal point on the Torino Scale, being, for decrease than a little while, a point 4, earlier it grow to be decreased.[7] Its diameter is approximately 270 meters (885 ft).[2] As of October 7, 2009, the opportunities of an April thirteen, 2036 impact are seen to be one million in 250,000.[3][8]

  • 1 decade ago

    An asteroid does not have to be very big at all to do a lot of damage.

    If it's moving fast enough, it could hit and destroy an area the size of Texas, the debris released would destroy all life on the planet by blocking out the sun and whatnot.

    There is no "right answer" for this question, because there are a lot of factors about it, that you would have to fill in.

  • Anonymous
    1 decade ago

    At typical impact velocities, an asteroid 10 to 12 miles in diameter with an impact point in the centre of the USA should take care of all you lot, and let some primitive civilization survive and re-emerge elsewhere.

    If it is 20 miles or more in diameter, it will be curtains down for humanity. Life will have to crawl out of the oceans again.

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  • 1 decade ago

    Something at least a mile in diameter, depending upon whether it strikes water or land. Hitting the Great Lakes or offshore in an ocean would produce tidal waves and flooding to half the country. Crop destruction would ensue, and famine. Striking land would produce dust clouds blocking out sunshine, and the sequelae would destroy most of the country.

    Something 5-10 miles in diameter would have global affect and knock human civilization back centuries.

    Source(s): This subject is treated in a fictional sci-fi novel called "Lucifer's Hammer" by Larry Niven, et. al.
  • 1 decade ago

    The Discovery Channel did a thing on the top 10 things that will and can destroy Earth. The asteroid was, I think, 5 or so. There will be a huge asteroid that will pass Earth around 2030's or something like that. Then it will come around several years later and might miss Earth by a teeny bit. Do some research on it. I am sure youll find it.

  • 1 decade ago

    The earth is 78% water, so, chances are, it would hit in water. The tsunami involved ( if the meteorite were, say 5 mi diameter) would be disastrous to ALL coastline areas of the whole earth.

    If such a meteorite hit THE U.S., or any land area for that matter, there'd be dust in the atmosphere, like what happened with the eruption of Krakatoa in 535 a.d., which lasted 3 years, and even changed certain civilisations on earth...

    Source(s): astronomer since 1944
  • 1 decade ago

    I'm thinking that it has to be bigger than what we are told!! Think about the mass and weight-ratio of the earth! I'm thinking with the size of the US the meteor would have to be the size of New Jersey and hit towards the center!!

    A meteor a mile or 10 miles across knocking us out like that!???

    I think the little small meteor making big fuss is a bunch of Bullshit!! The Mass of the Earth is too large!!

    Look at the craters on the moon!! The craters supports those so call Earth Killers!!

    Is the moon gone!!??????!!!???

  • 1 decade ago

    not very big at all. all you need is someone that everybody trusts to say on TV that an asteroid is going to hit the u.s. say a bulls eye on NYC, and you are going to get mass suicides and murder. so all you need is a lie and that's all it will take

  • 1 decade ago

    You're not doing some research...you're doing some HOMEWORK!!! You want others to do it for you? Well, I won't. I will give you an answer, though. It would have to be pretty big! Bigger than the White House and smaller than the United States.... Does that work for ya? hehhehe

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