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Project Icarus (Saturn + 100 Megaton Bomb)

moin1900

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Hi everybody

Project to carry a 100-Megaton bomb !
http://www.thespacereview.com/article/175/1
Many greetings
 

Skybolt

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I've never understood why the 100-megaton bomb unavailablity would have been a problem: just put 4 25-megaton bombs on that...
 

Michel Van

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Skybolt said:
I've never understood why the 100-megaton bomb unavailablity would have been a problem: just put 4 25-megaton bombs on that...

that easy, but has one big problem:
try to trigger 4 H-bomb simultaneously
is one to fast, its vaporise the 3 others
 

sferrin

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It would probably be easier to just add a 3rd and 4th stage to something like a B83
 

archipeppe

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OM said:
...It needs an astronaut riding the SM, waving a cowboy hat.

Mmhhh...you mean like this????
 

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Michel Van

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i read a Nasty comic story "Judas" by Richard Corben & Richard Margopolous

were Project Icarus is used to stop a Alien Invasion of Earth
with a 100 MT Cobalt-bomb and one Astronaut to fly the CSM to target.

but the Astronaut St. John is actually a Judas, kill Candidate to get this Flight
and try to make a deal with Aliens
there code of Honor give him a chance for duel with they Leader,
St. Johns wins and claim his new Empire, threatened ground controll He the “Lord of Universe"
will return to Earth to claim his homeworld to Empire after return from Alien HQ.

after the Com goes off one Scientists say to other:
"We had to tell him that radiation from Cobalt-Bomb is Deathly...."
"so Wat? had to be one way trip anyway" answer the other
lol
 

Rickshaw

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Michel Van said:
Skybolt said:
I've never understood why the 100-megaton bomb unavailablity would have been a problem: just put 4 25-megaton bombs on that...

that easy, but has one big problem:
try to trigger 4 H-bomb simultaneously
is one to fast, its vaporise the 3 others

Not impossible, just very difficult. Of course, it depends upon what sort of distance you want between the warheads exploding. Now, if you put in a radar proximity fuse which exploded when your four warheads are x distance apart, your detonation problem would basically be solved. However, what target would be worth four 25 megaton warheads or even worse, one 100 megaton warhead? I can't think of any, myself. One 25 megaton warhead would be sufficient to destroy most cities or missile silos.
 

starviking

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rickshaw said:
Michel Van said:
Skybolt said:
I've never understood why the 100-megaton bomb unavailablity would have been a problem: just put 4 25-megaton bombs on that...

that easy, but has one big problem:
try to trigger 4 H-bomb simultaneously
is one to fast, its vaporise the 3 others

Not impossible, just very difficult. Of course, it depends upon what sort of distance you want between the warheads exploding. Now, if you put in a radar proximity fuse which exploded when your four warheads are x distance apart, your detonation problem would basically be solved. However, what target would be worth four 25 megaton warheads or even worse, one 100 megaton warhead? I can't think of any, myself. One 25 megaton warhead would be sufficient to destroy most cities or missile silos.

The problem would be the margin of error on the radar proximity fuse. I'm guessing you'd need microsecond accuracy if you wanted the 4 25-megaton bombs to explode close enough to have the effect of one 100-megaton bomb.
 

Just call me Ray

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rickshaw said:
One 25 megaton warhead would be sufficient to destroy most cities or missile silos.

The concern was to deflect an oncoming asteroid. Most cities and even missile silos pretty much just sit on the surface, but an asteroid is at least a rough spheroid of half a kilometer in diameter of solid metal. According to the original link posted there were concerns if even a 100 megaton warhead would do the job.
 

sferrin

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Just call me Ray said:
rickshaw said:
One 25 megaton warhead would be sufficient to destroy most cities or missile silos.

The concern was to deflect an oncoming asteroid. Most cities and even missile silos pretty much just sit on the surface, but an asteroid is at least a rough spheroid of half a kilometer in diameter of solid metal. According to the original link posted there were concerns if even a 100 megaton warhead would do the job.

I'd think it'd be just a matter of F=ma. (of course I mean the complex version ;D). A 100 Mt bomb detonated on the surface of a 1km iron body will deflect it less than a 100 Mt bomb detonated 20 feet below the surface etc.
 

RP1

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A 100 Mt bomb detonated on the surface of a 1km iron body will deflect it less than a 100 Mt bomb detonated 20 feet below the surface etc.

Not necessarily. Very large explosives and nuclear devices have a problem in that most of the energy from the event is simply radiated out into space. To deflect an asteroid one would wish to make as much propulsive use of this energy as possible - a lot of the force would come from vapourised asteroid acting as a rocket, and burying the device may actually increase the propulsive force produced.

The problem is, of course, that a buried device may have a greater chance of fragmenting the asteroid, potentially making the situation worse (again, much of the energy of a single large impact may be radiated into space - several smaller impacts of the same total mass/KE could lead to more energy being input into the ecosystem, with potentially catastrophic results).

RP1
 

sferrin

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RP1 said:
A 100 Mt bomb detonated on the surface of a 1km iron body will deflect it less than a 100 Mt bomb detonated 20 feet below the surface etc.

Not necessarily. Very large explosives and nuclear devices have a problem in that most of the energy from the event is simply radiated out into space. To deflect an asteroid one would wish to make as much propulsive use of this energy as possible - a lot of the force would come from vapourised asteroid acting as a rocket, and burying the device may actually increase the propulsive force produced.

Which is exactly what I said.
 

RP1

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Yes, you are quite right - I misread "deflect" as "effect".

Note to self: in future, engage brain before keyboard.

::)
 

Orionblamblam

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Kids, kids, no need to fight! Let's just all agree that thermonuclear devices are extremely spiffy, and need to be used more often. Asteroid deflection, civil engineering, urban renewel, entertainment, etc.


And, note: a nuke set 20 feet from the surface of an asteroid *will* impart a delta V to it. A nuke set 20 feet below the surface *probably* will impart a delta V to it. There is a small but non-zero possibility that the nuke will crack the asteroid in half or split the asteroid in such a way that the net result of the deflection forces are zero. Even if you split an asteroid in half and impart a slight separation dV to the two halves, depending on the masses the dV might not exceed escape velocity and the two half will gravitationally recombine.
 

Skybolt

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And, note: a nuke set 20 feet from the surface of an asteroid *will* impart a delta V to it.
. Radiation and neutrons pressure, I think. There wouldn't be much debris to impart an Orion-style kick. And I suspect the "directed-effect" explosion trick wouldn't work with such a large weapon.
 

RP1

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Radiation and neutrons pressure, I think. There wouldn't be much debris to impart an Orion-style kick.

It's not the debris from the bomb in this case, but the debris from the asteroid. The energy from the device vaporises rock, which has to expand away from the asteroid. Conservation of momentum does the rest. This is the same effect that makes comets difficult to predict with absolute certainty - as they are heated by external solar radiation, jets of vapour & debris can alter their course.

Orionblamblam highlights the main problem, though - the offending object might not be solid enough for this to work.

RP1
 

Triton

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MIT Press is selling Project Icarus - Revised Edition.

This technological fantasy, the product of the MIT Students System Project and the inspiration for the 1979 film "Meteor," presents a plan for avoiding a hypothetical collision between Earth and the Apollo asteroid, Icarus, which sweeps by every nineteen years within a few million miles (a near-miss in astronomical terms). Collision with a four billion-ton rock would create a catastrophe equal to the destructive power of half a trillion tons of TNT.

To prevent tidal waves from washing away the coasts of North America and Europe and shock waves from fracturing the earth's substructure, the Project Icarus plan calls for six 100-megaton hydrogen bombs to be ready for liftoff in sequence from the Kennedy Space Center by six Saturn V rockets in an attempt to push the asteroid off course or to smash it into harmless debris. Clearly, money is no object; all the financial resources of the country are assumed available to the crack Project Icarus team. But time and accuracy are essential.

The description of the frantic project schedule from go-ahead to impact includes selection and modification of the launch vehicle and spacecraft; "design" of the nuclear warhead and prediction of its interaction with the asteroid in space; guidance and control of the spacecraft on its critical intercept trajectory; development of an intercept monitoring satellite to gather scientific data from the asteroid and the explosion; the tight management and rigid PERT schedule; and the economic impact of the project.

How close to Earth will Icarus's eccentric orbit carry it next time? What are the chances of some other, as yet undiscovered, asteroid—or worse, a random meteor—making its way straight for Earth? The MIT team's plan may yet be put to the test.
http://mitpress.mit.edu/catalog/item/default.asp?ttype=2&tid=6840

Attached illustration of a Saturn V converted for Project Icarus. This modified Saturn V resembles Saturn INT-21. The drawing is from the March/April 2000 issue of Sport Rocketry magazine, the official journal of the National Association of Rocketry. (Illustration by Pete Alway)
 

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Lauge

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Orionblamblam said:
Kids, kids, no need to fight! Let's just all agree that thermonuclear devices are extremely spiffy, and need to be used more often. Asteroid deflection, civil engineering, urban renewel, entertainment, etc.

Casaba Howitzer! Turns a boring day into a fun day ;D

Seriously, though, wouldn't a CH style warhead be useful for this sort of thing ? Using a MIRV-type bus for maybe 5 or 10 independent warheads, shouldn't we be able to get enough separation between them at T-0 to avoid fratricide ? Since the CH wouldn't need to be in physical contact with the target ?

As an aside, according to a calculation at http://www.projectrho.com/rocket/rocket3x.html#nuke, the maximum range to a target at which a 1 MT nuke will produce impulsive shock is about 570 meters. Impulsive shock means that the radiation energy from the blast vaporizes the surface of the target fast enough to set up a shockwave in said target (i.e., the surface layer of the target is vaporized at a rate exceeding the speed of sound in the material). And 570 m is real close at interplanetary distances and velocities.

Regards & all,

Thomas L. Nielsen
Denmark
 

Michel Van

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David S. F. Portree on project Icarus
http://robotexplorers.blogspot.com/2009/07/project-icarus-1967.html
http://robotexplorers.blogspot.com/2009/07/project-icarus-alternate-history.html

Project Icarus had plan to send
not one Interceptor with a 100 Mega tons Bomb
but 5 Interceptor with a total of 500 Mega tons !

launch in interval of 14 day

the Interceptor near Icarus to 550 feet, (167,64 meters)
then a radar would detect Icarus and trigger the nuclear device,
which would explode at a distance of from 50 to 100 feet. (15,24 to 30,48 meters)

intresting is Portree Wat If?
Apollo is push up to year 1970
Icarus use 7-8 Saturn V
2 for Test flights (SA-501 and SA-503)
1 strandet Interceptor with SA-502 in low orbit :eek:
5 launch Interceptors (SA-504 to SA-509)

if they chancel production of Saturn V in 1968
Then NASA hab only 4 Saturn V for Apollo Program
and that under President Richard M. Nixon !
 

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Interesting exercise.

I think the reality has become obvious (with these days of the NEAR spacecraft and so on) that nuking an asteroid may not be the best solution. Some asteroids may be hardly more than masses of dust and rock that have happened to accumulate over millions/billions of years. A lot of thought would have to go into understanding the target in order to take practical steps against it.

Though, in some instances, something like this may be just what the doctor ordered.
 

SAustin16

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I find it rather sad and frustrating that:

1. We have no flyable Saturn V boosters (or similar booster) in case we actually need them.

2. Jupiter was recently hit by an asteroid, and it took an AMATEUR Australian astronomer to notice the Pacific Ocean-size impact.

The entire planet is woefully unprepared for this type of event, though we have the technology to improve our situation in regards to detection and influencing our outcome.
 

Triton

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SAustin16 said:
I find it rather sad and frustrating that:

1. We have no flyable Saturn V boosters (or similar booster) in case we actually need them.

2. Jupiter was recently hit by an asteroid, and it took an AMATEUR Australian astronomer to notice the Pacific Ocean-size impact.

The entire planet is woefully unprepared for this type of event, though we have the technology to improve our situation in regards to detection and influencing our outcome.

We really have much more important things to be concerned about than the possible planetary impact of a near-Earth asteroid. The next most likely suspect is 99942 Apophis that has a 1 in 250,000 chance it will impact the Earth on April 13, 2036. With those odds, can we really justify diverting the huge sums of money from other public projects to create and maintain a planetary defense infrastructure that would include creating launch vehicles, launch pads, and possibly half-a-dozen 100 megaton nuclear devices? How much will it cost to maintain these launch vehicles on constant stand by? Will they function when needed? After spending trillions how many years of credible defense will they provide until they need to be upgraded or replaced?

Which country or political body has launch authority? Which country will "host" this planetary defense system and is it possible that this system might be used in a war on Earth?

There are much more probable natural disasters for which we have not maintained our defenses and the trillions would be much better spent preparing for these than a planetary impact. The neglected levee system of the City of New Orleans comes immediately to mind.
 

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Respectfully, I don't think we have an option as a species to not have some kind of system in place. Back in 2005, NASA spoke about Apophis, here:

http://impact.arc.nasa.gov/news_detail.cfm?ID=166

We are talking about events that have an extremely low probability, but similar events ended the reign of the dinosaurs. Impacts of these scale still happen in our solar system, as SAustin16 pointed out, as we've just seen dramatically with Jupiter.

I'd like to suggest we are smarter than dinosaurs. At least, I hope we are.

The above articles note that something detected at about the distance of Jupiter's orbit could give us only nine months or so to address it. We could in fact be "blindsided" by the Sun's glare by objects moving past their perihelion, which would give us far less time to react.

I wrote some suggestions about using an Orion-style approach about this problem some time back in a post on my blog I called "Dr. Dyson's Space Patrol." --

http://www.danielbrenton.com/2009/02/26/dr-dysons-space-patrol/

Not that I'm "anybody," but I at least wanted to say it.

We can't afford not to do something, and it doesn't matter who takes the authority to do it. Someone has to "man up" (ladies, forgive the expression, but I think you get the idea). I suggest America do so.
 

OM

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Which country or political body has launch authority? Which country will "host" this planetary defense system and is it possible that this system might be used in a war on Earth?

...I nominate American Samoa. Just because.
 

Orionblamblam

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Triton said:
With those odds, can we really justify diverting the huge sums of money from other public projects to create and maintain a planetary defense infrastructure that would include creating launch vehicles, launch pads, and possibly half-a-dozen 100 megaton nuclear devices?

*Snort*

Yes. Rather obviously.

How much will it cost to maintain these launch vehicles on constant stand by?

A small fraction of the amount that will be expended on the US government takeover of the health care industry.


Which country or political body has launch authority?

Whichever country builds it.

Which country will "host" this planetary defense system and is it possible that this system might be used in a war on Earth?

Yup! That's actually one of the great things about it. It's not like you could use it for a sneak attack. and its use would n ot destroy a major powers ability to launch a counterstrike. And yet, its existence would require the development of a countermeasure. Which would lead to deep-space interception systems by the other powers, which would require a drastic drop in launch costs and an increase in space-capability.

All for the best.

Additionally: 100 megaton nukes are ridiculous weapons. While everyone that coudl tried to jack up thermonuke yields into the multi-megaton range back in the day, most nukes these days are in the hundreds of kilotons. Because that's more or less the optimum yield for flattening cities and the like. A 100 M-ton nuke would be wasted energy..
 

SAustin16

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Though I can't argue too much about the probability of the Earth being hit by a significant object, the reality is that Jupiter was hit with a multiple-impact in 1994 and then again 15 years later (almost to the day). The question now is how often have planets been getting hit in the recent past, with no one on Earth noticing. I do realize that the Earth's smaller gravitational field may reduce our chances, but "probability can be a funny thing".

We're willing to spend trillions on weapons that can destroy our planet, but we're unwilling to spend money on an adequate system to save ourselves. Icarus may not be the answer, but we'd probably learn a lot devising a workable solution.

In the immortal words of "Goose" in Top Gun ... "Your sons died because they were stupid".
 

DanielBrenton

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SAustin16 said:
Though I can't argue too much about the probability of the Earth being hit by a significant object, the reality is that Jupiter was hit with a multiple-impact in 1994 and then again 15 years later (almost to the day). The question now is how often have planets been getting hit in the recent past, with no one on Earth noticing. I do realize that the Earth's smaller gravitational field may reduce our chances, but "probability can be a funny thing".

We're willing to spend trillions on weapons that can destroy our planet, but we're unwilling to spend money on an adequate system to save ourselves. Icarus may not be the answer, but we'd probably learn a lot devising a workable solution.

In the immortal words of "Goose" in Top Gun ... "Your sons died because they were stupid".

Hear hear!

At least there are a few of us in this world that DO "get it." Hopefully, that's a start.
 

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Maybe someone on the forum can help me with a source for this: I seem to remember reading, a few years back, about a NASA study on the risk of an asteroid impact. Risk, in this case, being defined as the combination of probability and consequence, i.e. how likely is an impact, and how much damage would it do. Supposedly, this NASA study showed that a catastrophic asteroid/comet impact (think dino-killer) is highly improbable. However, if it did happen, it would wipe out a significant percentage of all life on the planet. Consequently, the risk to the individual human of dying in an asteroid impact is about the same as the risk of dying in an airplane crash!

Does anyone know more?

Regards & all,

Thomas L. Nielsen
Denmark (presently Luxembourg)
 

Nik

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Topical impactor: 10 metre lump, ~50 kt bang.

http://neo.jpl.nasa.gov/news/news165.html
quote:
On October 8, 2009 about 03:00 Greenwich time, an atmospheric fireball blast was observed and recorded over an island region of Indonesia. The blast is thought to be due to the atmospheric entry of a small asteroid about 10 meters in diameter that, due to atmospheric pressure, detonated in the atmosphere with an energy of about 50 kilotons (the equivalent of 110 million pounds of TNT explosives).
/

FWIW, the Indonesians have not been too lucky recently, but they dodged this bullet...
 

mz

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Umm, those asteroids are really small. Most are.
You can check the scales here:
http://neo.jpl.nasa.gov/risk/

The much waffled about Apophis is a few hundred meters in diameter. Hitting a city would be a bad thing, yes, but a 100 km away you'd be fine. Hardly dinosaur killing here.

You can estimate impact effects here:
http://www.lpl.arizona.edu/impacteffects/

A 6 km asteroid would require more distance for survival, say in the thousands of kilometers magnitude. 10 km is dinosaur killer territory.
 

blackstar

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mz said:
1-The much waffled about Apophis is a few hundred meters in diameter. Hitting a city would be a bad thing, yes, but a 100 km away you'd be fine. Hardly dinosaur killing here.

2-You can estimate impact effects here:
http://www.lpl.arizona.edu/impacteffects/

3-A 6 km asteroid would require more distance for survival, say in the thousands of kilometers magnitude. 10 km is dinosaur killer territory.

1-You'd need more than 100 km, probably. A hit in the ocean (most of the world is ocean) would probably not affect anybody unless there was a ship underneath.

2-The impact effects may be adjusted. New research--still not independently confirmed--suggests that smaller bodies can cause more damage.

3-Your figures are wrong. The generally accepted lower boundary for impacts with globally catastrophic damage (i.e. a dinosaur killer) is around 2-3 kilometers. 6 would be devastating.
 

blackstar

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By the way, NASA has currently detected around 85% of the objects 1 kilometer in diameter or greater, with a goal of detecting 90%. (Calculating both the size of detected objects, and guessing at the total population size, are difficult to do and not precise. The size of objects is calculated based upon how bright they are. And this is based upon an average estimate of how bright they _should_ be. Change that estimate a bit, and you have to recalculate the sizes of all the objects that you've detected, and of course this changes the estimates of how many objects of each size are out there.)

The real question is the smaller objects. There is a detection goal for near-Earth objects 140 meters in diameter or greater. Only a small fraction--perhaps 5-10%, of those have been detected. Congress has established a goal to discover 90% of those. But more of them cannot be detected unless new (expensive) telescopes are built. In recent years, there has been some research--still unconfirmed--suggesting that objects as small as 30 meters could cause significant damage if they hit near a population center. However, it is virtually impossible to detect such small objects until right before impact.

The more you study this issue, the more you appreciate how much is unknown, or hard to determine.
 

mz

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blackstar said:
mz said:
1-The much waffled about Apophis is a few hundred meters in diameter. Hitting a city would be a bad thing, yes, but a 100 km away you'd be fine. Hardly dinosaur killing here.

2-You can estimate impact effects here:
http://www.lpl.arizona.edu/impacteffects/

3-A 6 km asteroid would require more distance for survival, say in the thousands of kilometers magnitude. 10 km is dinosaur killer territory.

1-You'd need more than 100 km, probably. A hit in the ocean (most of the world is ocean) would probably not affect anybody unless there was a ship underneath.

2-The impact effects may be adjusted. New research--still not independently confirmed--suggests that smaller bodies can cause more damage.

What's your source for the new research / more than 100 km? We're talking hydrogen bomb scale energies here. 60 megatons. Don't know if there would be a tsunami.

http://neo.jpl.nasa.gov/risk/a99942.html
http://www.lpl.arizona.edu/impacteffects/cgi-bin/crater.cgi?dist=100&distanceUnits=1&diam=270&diameterUnits=1&pdens=&pdens_select=3000&vel=13&velocityUnits=1&theta=45&wdepth=&wdepthUnits=1&tdens=2750

At this impact velocity ( < 15 km/s), little vaporization occurs; no fireball is created, therefore, there is no thermal radiation damage.

Richter Scale Magnitude: 6.4

At your position there is a fine dusting of ejecta with occasional larger fragments
Average Ejecta Thickness: 923 micrometers = 36.3 1/1000 of an inch
Mean Fragment Diameter: 2.29 cm = 0.9 inches

The air blast will arrive at approximately 303 seconds.
Peak Overpressure: 6510 Pa = 0.0651 bars = 0.925 psi
Max wind velocity: 14.9 m/s = 33.4 mph
Sound Intensity: 76 dB (Loud as heavy traffic)

The take home message from this for me is a regional catastrophe. A huge number of people have died in the recent Chinese earthquake or the Tsunami and people in the west hardly remember even when those were. This could of course kill millions if it hit a city.

I'm not opposing watching and even deflecting asteroids. But painting world-apocalyptic pictures because of Apophis is very misleading. At least for me the low impact effect estimates came as a surprise when checking them with the the web application.

3-Your figures are wrong. The generally accepted lower boundary for impacts with globally catastrophic damage (i.e. a dinosaur killer) is around 2-3 kilometers. 6 would be devastating.

Oh, yes, I probably am. References? The dinosaur killer was estimated 8-10 km diameter.
 

blackstar

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I don't have my paper references in front of me right now, but you'll see here:

http://users.tpg.com.au/users/tps-seti/climate.htm

It lists 5 km as the size for "global" effects, such as "day turns to night for months." That's actually the middle boundary estimate. As I noted, 2-3 km is generally accepted as the "lower boundary" for such effects. Everybody argues over this, but several kilometers is considered the point where things get bad "globally."

You can also go to the NASA 2006 Near-Earth Object Survey and Deflection Study, page 24, where a table lists "nominal global effect" with "fatalities per impact greater than 1 billion" starting at "greater than 1 kilometer." "High global effect" is considered to be "greater than 5 kilometers" with fatalities of "greater than 2 billion." It lists an "extinction class event" as "greater than 10 kilometers" and fatalities of "6 billion."

But, as noted, those are considered the "average" values, and some people argue that it is necessary to be conservative (in terms of safety) and err on the side of caution, and so they take the lower boundary values. (In practical terms, this means that you want to search for asteroids a few kilometers big, rather than only for the really big ones. And that's what the congressionally-mandated surveys do.) We're talking points on a curve here, so it all depends on where someone wants to draw their line--at the top of the curve, or somewhere else? Some people take lower points on the curve, so "greater than 5 kilometers" has a range, and some people pick the lower range at 2-3 kilometers. You're right that they're not of the dinosaur killer range, but they're still highly destructive. Billions of fatalities is considered a bad thing.

None of which has anything to do with advanced spacecraft, so I'll stop leading off topic now.
 

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