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Earth almost put on impact alert

  1. Feb 25, 2004 #1

    Ivan Seeking

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  3. Feb 25, 2004 #2


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    Neato...since it didn't hit of course.

    30 meters is getting close to the size of the Tunguska Impact.

    Guess we need to spend more $/time on asteroid detection.
  4. Feb 26, 2004 #3
    At the end it says it was actually 500m across as they found out later.

    scary eh?
  5. Feb 26, 2004 #4


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    My question is...if the alert did go to the president, would they alert the public?

    Would it be wise to alert the public? Would it do more harm than good?

    If we knew that an asteroid would impact the earth in 36 hours, in the northern hemisphere (as this one was projected), what could be done? I could see mass panic and lots of people getting killed. What positive outcome could be gained from alerting the public?

    Then if they *don't* warn the public, there will be outcrys from the populace about no warning.

    I just know that I personally will be able to sleep better at night knowing that if this does ever happen, President Bush will be safe in his underground command center while the rest of us are left to our fate.
  6. Feb 27, 2004 #5


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    It seems that is a matter of ongoing debate.

    36 hours...you may be able to evacuate certain regions in order to minimize the loss of life

    If it was more like 36 months, then you may be able to mobilize more resources to deflect the threat.

    Yep. Guess the decision-makers would have to weigh that against the risk of the chaos.

    The more amateur astronomers we have out there, the less likely something like this could be hidden. The PF A&C forum proudly supports amateur astronomers everywhere!
  7. Feb 27, 2004 #6


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    I think the main risk in such an impact would be its strong resemblance to a nuclear attack. The air-burst, the size of the blast, even a mushroom cloud! This could have provoked whatever country got hit into "retalliating" against whomever they think would be likely to hit them. In this light, it is more important for world leaders to know than for the general public. However, I think if Bush had been notified, he would have announced it to the public. Just my impression.

    But the real fright for me is not these "false alarms". Rather, it is the number of times an asteroid big enough to do serious damage has been detected after a close flyby. So whether or not to warn the public in advance may be a moot point, since the odds are next time we take a hit, the first peice of information we will have will be the impact itself.
  8. Feb 27, 2004 #7
    A lot of things can be done in 36 hours.

    36 hours is long, if you think about it. I mean, we sleep through a lot of that time but during panic that isn't going to happen.

    They must alert the public. If they don't...I'm trying to think of a correct way to put it:

    "It's their ass."

    Political leaders can forget about being reelected, and NASA can forget trust.

    Maybe they can get Boeing to send planes and fly people out of the place?

    Unlikely, but if the world cooperates....
  9. Feb 29, 2004 #8
    Now.....not so much about the discovery of the asteroid and the evacuation!

    All of us noe that even though 36 hours isn't a short time and if the asteroid was to hit us, it isn't enough to transport the whole population on earth of to another place, but is on how the people would do to prevent this castastrophy!

    eg:like could we do something to divert the asteroid off in another direction???
  10. Feb 29, 2004 #9
    It is at times such as this, that I wished that we lived in a fiction world, like the one in the movie 'Armageddon'. I know most of you would call my fear irrational, and I know that the chances of dying from other phenomena are greater, but this still has me staying up nights. :frown:
  11. Feb 29, 2004 #10


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    The article stated that in 36 hours the asteroid could impact somewhere in the northern hemisphere. How is the entire population of the northern hemisphere going to evacuate? There is no way that an announcement like this could do anything but major harm. There would be mass hysteria unlike anything ever seen.

    Can you just imagine an announcement like that?

    By the time they would be able to narrow the impact area down, it would be too late. As Lurch said, more than likely there won't be time for a warning, these objects are hard to detect.
  12. Feb 29, 2004 #11


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    Unfortunately we don't have the ability yet to succesfully deflect asteroids, especially one that close. There are too many variables. You can't try to destroy it because that could cause even more widespread devastation from breaking it up into "many" pieces that would hit the earth.
  13. Mar 4, 2004 #12
    Actually, I don't think it is clear that breaking up a larger asteroid into smaller ones is a bad things. For one thing, in such a case, not all of the pieces would necessarily hit the Earth, and those that do would probably do so in geographically disparate areas. Breaking the asteroid up creates a greater aggregate surface area for the same aggregate mass. This means more of that mass would burn away in the atmosphere further reducing the mass that actually makes impact. (In the most extreme case, where the asteroid is reduced to dust or small rocks - there is no impact whatsoever.)

    Having say 5 separate impacts each with 1/5 the mass and hence packing 1/5 the punch separately is not the equivalent of a single massive impact.

    Alas, in order to break up the asteroid it would be necessary to rendezvous with it, and bury the appropriate explosives inside it. In that case, it would probably be more sensible to give it a nudge and put it on a different trajectory.

    Exploding a nuclear bomb right next to it might not do any good as a nuclear explosion in the vacuum of space would impart virtually no impulse to the asteroid unless the heat released by the explosion caused it to vent out. Otherwise it would only raise its temperature by causing it to absorb high-energy neutrons from the nuclear blast.
  14. Mar 4, 2004 #13
    The more quickly an asteroid is discovered that threatens Earth, the better. It takes relatively little delta-V to cause it to miss Earth.

    Recently someone proposed attaching a low but continuous thrust engine to such asteroids as a way of protecting the home planet in the event one were discovered.
    Last edited: Mar 4, 2004
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