Simulation Of An Asteroid Impact In The Year 2880 411
JoeRobe writes "Researchers at UCSC have simulated a possible outcome of an impact by asteroid 1950DA when it passes near us in the year 2880. Note that there is a 0.3% chance of impact during that encounter. In the event that it impacts in the Atlantic, they predict that the '60,000 megaton blast' would create 400 foot waves along the east coast. In addition to an assessment of the danger, their studies point out the resulting geologic features that we should be looking for now, which would indicate where and when such impacts have occured in the past."
Re:Uhm... (Score:5, Informative)
For older and larger impacts, you're looking for very different evidence: heavily brecciated rocks, shock quartz crystals, changes to crust/mantle interface, evidence of high pressure rocks. Further afield, evidence of global dust layers (esp contaminated with terrestrially unusual minerals such as iridium), evidence of "tidal wave" eg poorly structured jumbled marine deposits over a large area.
Re:90 Percent? (Score:5, Informative)
Budget constraints. They can only do so much with what they could sqeeze out of the government.
Seriously, it could be because of the unpredictability of the asteroids' path & other unknown asteroids. Although many of these follow well defined path - a smallest deviation resulting out of say, collision with other space debris, would mean large change from the expected point of contact at earth.
Re:One things that I haven't seen addressed ... (Score:5, Informative)
Whether the asteroid hits or not will determine whether 0.5*m*v^2 joules of energy will be unleashed or not. Observe that angle or shape or composition don't enter the equation (and rotational energy is quite insignificant in comparison). The only parameters are the boolean value "hit", total mass, and velocity.
What you're talking about are secondary details on "how" the energy will be transferred, but regardless the total amount will be the same.
how about another or two (Score:5, Informative)
I doubt there are as many distinct/unique hit scenarios as some would propose. This isn't a weeked destruction derby, with hollowed out Cadillacs bouncing off each other in a mud pit.
Next, asteriods are not known for their 'rotation' as much as they are for tumbling. Neither of which matters much as the gases and kinetic energy involved in a strike will have their way long before actual contact of the two entities. Much like an avalanche, or tsunami, the bulk of the damage is from the shock and pressure wave(s) that arrive before the object/event itself. Contact is after the fact, and I don't think anyone is going to come out from under their desk saying "man! that was close! Good thing it only grazed us!" In this case, a miss really is as good as a hit.
Re:Actually... (Score:2, Informative)
A picture is worth a 1000 words (Score:5, Informative)
Pic [ucsc.edu]
Re:Here it is (Score:2, Informative)
Or this one [bbc.co.uk], or this one [virginia.edu], or this one [nasa.gov], or this one [arm.ac.uk], or my favourite: this one [imagesofspace.com].
Artists seem to like to portray asteroids as being sveral hundred kilometres in size.
this is old news... (Score:3, Informative)
according to this story [yahoo.com], this simulation was done on a debian cluster running the hurd.
check out the date, it was published months ago.
Re:YES!!! (Score:3, Informative)
Pretty much irrelevant. The asteroid would hit at a velocity 300 times faster. The energy is one-half mass times velocity squared. That "squared" part means you are looking at 90,000 times as much energy per unit of mass. That's enough to vaporize not only your car but a huge section of the wall as well.
Then consider the fact that the asteroid is around a billion times more massive than your car. You're looking at about a hundred trillion times as much total energy. The atmosphere wont noticably slow it down even on a "grazing" angle. If it touches the ground at even a 2 degree angle you vaporize not only the asteroid, but several cubic kilometers (or cubic miles) of the earth as well. Heck, the grazing hit could be worse. A direct hit would sink much of the energy downwards into the earth to dissipate. A grazing hit would vaporize a long shallow stretch of the surface dumping the energy where it can do the most harm.
A few of the details may vary, but the general result is the same.
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