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120,000 km Is Still Too Close
texchanchan writes: "BBC report: '...on 14 June, an asteroid (maybe as big as 120 meters in diameter)... made one of the closest-ever recorded approaches to the Earth.
..' but was only discovered three days later. This is well within the moon's orbit. 'If 2002MN had hit the Earth, it would have caused local devastation similar to that which occurred in Tunguska, Siberia, in 1908...'"
My favorite quote is from Dr. David Morrison
We had to destroy the sig to save the sig.
In all fairness, the article states that the path of the asteroid was on a line with the sun. There is no way Earth based telescopes could have seen it, even had they known exactly where to look.
This will become more scary in the future, when there is some capability to deal with an asteroid on a collision course. When we get to that point, we'll be complacent and will eventually end up being sucker-punched by one of these asteroids coming "out of the sun".
120,000 km sounds close, but consider this:
The Earth is about 7,926 miles (12,756 km) in diameter. Roughly 12,000 km, or about a tenth of the flyby distance. The chance of any object that comes within 120,000km of actually hitting the earth is about (0.1)^2, or roughly 1%. This is still unsettlingly likely, but it's not exactly doomsday.
I used to bulls-eye womp-rats in my pants
Yeah, but if you crash on the highway, you and your kids might die. If an asteroid hits the earth, millions or billions could die. So on a personal level, driving is more dangerous, but we're talking about the survival of the species here. It's not something to ignore.
---- El diablo esta en mis pantalones! Mire, mire!
Incoming asteriod is a point particle.
Diameter of the Earth is 12,000km.
Asteroid will pass within 120,000km of Earth's center (possibly less).
The question then becomes:
Choose a random point within a circle of radius 120,000km.
What is the probability that this point lies within a circle of radius 6000km?
In other words, what are the relative sizes of the two circles?
(pi * 6000^2)/(pi * 120000^2) = 0.0025 = 0.25%
-- Brian
The most rabid believers in American Exceptionalism are the exact same people whose policies are destroying it.
What Verhoeven and his cronies did with the movie was turn the Federation into an actual fascist state. As the linked webpage states, Verhoeven's statement that...
"The philosophy of Heinlein is certainly in the movie. Whether I adhere to that society myself is something else, but it is the philosophy of the world he described, and we took that from his book."
...is total bullshit. Purposely or not, Verhoeven et al got Heinlein's philosophy all fucked up. So the movie ends being a pretty good action flick, with a kinda anti-war message from its over-the-top portrayal of a fascist state, if you really try to analyze it. Of course, there's really no point in doing that, because Heinlein's novel discusses a lot more stuff a lot better, and Verhoeven didn't pick up any of it in the 5-minute read he gave it before directing the movie.
>>France's solution to unemployment is to make it so you can't work more than 35 hours a week.
:)
>That actually makes sense.
You're an idiot.
When supply (or potential supply) exceeds demand, prices are driven down. Nearly everyone can afford basic food.
So if only 10% (or 1%, more realistically) of the population can provide basic nutrition and shelter for everyone, then the other 99% provide non-essential quality of life improvements, or "amusement". And that's pretty much what's going on today -- most everyone works far more than would be required for basic sustenance. The problem is that people are quick to become accustomed to this new, "better" way of life. They might be working lots of hours, but they have kids, a sturdy house, cars, etc., none of which are actually required to live.
Those who, for whatever reason, do not provide amusements that other people want, end up living in "poverty". Which is what, really? A life with little or no amusement. You don't amuse them, they don't amuse you. "Poverty-stricken" people are still ALIVE, though. It's really, really hard to actually starve to death today in industrialized nations. Charity is abundant.
I think it's fundamentally broken to say that people have a right to be amused, and have things that aren't essential to actually staying alive. Because of charity, people are easily kept alive, and anything beyond that falls in the "amusement" category. If you think that people have a right to be amused without amusing others, then by all means spend your time and resources amusing them. But I don't think it's right to force me to amuse someone who won't amuse me back.
If you get my drift.
Alex, who's waiting for the robots to take over the menial jobs, so we can all just sit back and amuse each other.
Even then, it's not what you would think. The thermal effects scale almost linearly with yield, but the blast effects follow the inverse square law.
A 100 MT bomb is only about three times more powerful than a 10 MT bomb as far as blast effects go.
For this reason, all the larger bombs were abandoned in favor of smaller and more managable ones. They also use MIRV clustering now. Just image a beo...
nevermind.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
"If 2002MN had hit the Earth, it would have caused local devastation similar to that which occurred in Tunguska, Siberia, in 1908, when 2,000 square kilometres of forest were flattened."
r e&AD2=&AD3=new+york%2C+ny&AD4=U.S.&x=0&y=0
in case you haven't done the math yourself (and you likely haven't), 2,000 sq km is something like 1200 sq. mi., which is about a radius of 20 miles from the point of impact.
http://pbs.vicinity.com/pbs/blast.hm?SEC=25pressu
just to draw a(n) (in)comprehensible comparison, check out this map of a 25 megaon bomb being detonated over ny (or any other city)...
Satanists get good grades too...suspiciously good grades
You know what would be ironic? If a good size asteroid hit the Earth, enough to kill millions of people but not billions, say, and that explosion mistakenly triggered a Russian nuclear attack on the U.S., and then the U.S. responded...
Nope. Not gonna happen. Why? Two-Phase burst. Nuclear detonations have a characteristic visual signature:
1) Initial EM burst (Mostly hard gammas and X-Rays, but also visual)
2.) Air burned opaque by X-Rays, shockwave causes air compression and ignition.
An asteroid impact would lack this signature and
not be registered by the satellites that watch for this type of event. As asteroid airbursts of kiloton and greater size occur with regular frequency, they would certainly know the difference.
Simplistic summary by non-Physics major. Feel free to poke holes in it.
Wanted: One witty yet thought provoking