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B Ideas to protect the Earth from possible asteroid impacts

  1. Nov 1, 2018 #1
    Do you have any own idea, on a way to protect the Earth from a possible asteroid impact?

    (You can not use technologies that are not invented yet, or imaginary. Those that can be invented in the next, let's say, 10 years, are allowed)
  2. jcsd
  3. Nov 1, 2018 #2


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    What ideas has your research found so far?
  4. Nov 1, 2018 #3


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    First things first. Detection long enough in advance is necessary to do anything.
  5. Nov 1, 2018 #4
    Not really.
    If the object is massive enough and it's trajectory intersects with Earth, it will do massive damage.
    Ideas suchlike we could nuke it don't work, Earth still gets hit but by a bigger number of fragments.
    That might make things even worse.
    As pointed out by mathman though, if it was seen coming early enough, we might be able to push it away with rockets or something.
  6. Nov 2, 2018 #5

    Two projects have resulted in landing probes on asteroids Ryugu and Churyumov.
    If they can do that now perhaps in 10 years they could land a manned mission?
    Once we have scientists there, they can work out how to deflect it, whilst carrying out important work involving the formation of the solar system.
    A sort of two birds one stone scenario.
  7. Nov 2, 2018 #6
    The two main proposed methods are either ramming a spacecraft into the asteroid at high velocities or landing and setting off a nuke on the surface. Both method's goal is only to slightly nudge the asteroids trajectory and require enough lead time to be effective. There is still work being done to map out and discover every threat to the earth that is out there in the solar system. Right now we don't have a solution if we only have a short time in advance notice such as the case in the movie Armageddon.
  8. Nov 7, 2018 #7
    There is another idea which I think was in the movie Armageddon from '98. Instead of blowing up a nuke on the surface, you drill into it and blow it up from the inside. This way you split the asteroid and then the larger pieces will be pushed away from Earth without changing the momentum of the asteroid.

    Obviously this would cause other problems like having radioactive asteroid pieces shooting towards earth but its an interesting concept. There are some clips from the movie on Youtube that you can find that you might enjoy.
  9. Nov 7, 2018 #8
    @NateTheGreatt77 movies are for entertainment and are generally very unscientific. There are numerous major flaws with that strategy such as the window being to small, the depth required to dig, what would actually happen when the nuke went off, the technical difficulties of bringing the tools to the surface and also actually drilling the hole. The two methods I mentioned previously are the only two known feasible ones right now.
  10. Nov 8, 2018 #9
    It is a gruesome question, so we may as well consider a third class of methods that desperately suggests moving the Earth to dodge the hazard. This class of methods would bear unimaginable consequences even if successful, the only consideration being the possible avoidance of Earth's complete destruction.

    There might be two general proposals to accomplish this. One might be to move the Earth indirectly by displacing the Earth-Moon barycenter by directly moving the Moon, the other might be to move the Earth directly.

    With sufficient lead time and planning, moving the Moon might be the more attractive approach of this class if the long term result is that the Earth stays near its present orbit. So, perhaps this is a series of thermonuclear detonations (possibly consuming the whole world's nuclear arsenal) at a region on the Moon, positioned and timed to induce the Moon to shift orbit and dislocate the Earth-Moon barycenter enough for the Earth to miss the hazard.

    With less lead time and more panic, moving the Earth directly may be the much more desperate approach but one which is designed to keep the long term Earth orbit near its present orbit. So, perhaps this is thermonuclear detonations over a large region on the Earth's equator, the resulting revolving continental fire timed to push the Earth out of and back into orbit during one revolution, the thrust coming from the fire.

    Forest fires release on the order of 1 megawatt per second per acre of fire area
    The Amazon has 1.4 billion acres of forested area
    An Earth revolution is 86,400 seconds
    So, about 10^23 Watts

    I guess about half of that power would be available to displace the Earth and the other half would be needed to put it back, but both shifts would be curved paths, the minimum displacement would need to be at least one Earth radius for "small" hazards, and would need to be further for hazards big enough to suffer tidal demolition... I wonder if, and how big (or how slow) a hazard could the Earth miss with that power..?
  11. Nov 8, 2018 #10


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    I think we had a posting here a while back where it was discussed if a person could push a big boat away from the dock, and with his tiny push compared to the mass of the big boat, it would be possible.
    I have wondered though that with the new and improved orbit of the asteroid, how much time ( or orbits ) would it take for the earth-asteroid to intersect once more.
    Maybe never.
  12. Nov 18, 2018 #11


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    Nukes are the best way to go. I’m sure we’ve all heard the objections that using a nuclear weapon against a potential impactor will “turn one rock headed for the Earth into thousands of rocks headed for the Earth”. I hope that most people in these Forums can see the flaw in that statement.

    The best course of action I can see would be a series of large thermonuclear devices, aimed at various points along the trajectory of the threat. As with any practical method of interception, early detection and accurate plotting are the key. If the first blast does break the object into many pieces, any of those pieces that are still on course to strike the Earth will pass through the later intercept points, and be hit again. The first strike should be a “bunker buster”, designed to punch a hole deep into the object before detonating. The follow-up blast could be the “stand-off” detonations often proposed for these scenarios.
  13. Nov 18, 2018 #12
    Would a base on the moon be better for this?
    Assuming money was available? Less gravity and friction for launching?
  14. Nov 18, 2018 #13


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    I was actually thinking of the devices in orbit around the Moon. Final assembly would take place in that orbit, just to avoid some of the political obstacles to the plan. Once the threat is detected while still many years away, the launch (escape burn, more specifically) could be timed to whatever moment is most advantageous, using the Moon’s motion to speed the devices on their way.

    Much of the problem with using nukes is the fear that the one controlling the devices might decide to use them against someone here on Earth. This eliminates that threat, since any attack would take days to arrive.
  15. Nov 18, 2018 #14
    Yes It would have to be a global collaboration money wise and security wise.

    If they can put together funds and technology for the James Webb then a missile station in orbit must also be possible
  16. Nov 19, 2018 #15
    If you are going to make space installations I would think something like a rail gun would be more practical (potentially with nuclear rounds). It could be solar powered and store the energy over long periods of time. The biggest Issue i can see is that the shots would alter its course. maybe on the surface of the moon may work better. But, that is a rather expensive investment for something may never be used or may not even be very helpful when it is used.
  17. Nov 19, 2018 #16
    It all depends on the size, what it's made of, and how soon we detect it. Nukes would be entirely useless against an asteroid the size of Ceres.
  18. Nov 19, 2018 #17


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    ohhh .... I would love to hear your opinion/reason
  19. Nov 20, 2018 #18
    What are you talking about?? Moving either the Earth or the Moon by even a microscopic amount is totally beyond our capabilities in the next few thousands of years. Moving an asteroid is way more practical.
  20. Nov 20, 2018 #19
    Why this idea that "nukes wouldn't work" persists for so long? Try doing some back-of-envelope math. Nukes seem to work, unless we talk about 10+ km sized objects.
  21. Nov 20, 2018 #20
    That is what I thought we were talking about.
    Sure enough, if it was a 1 km meteor, a nuke could do the trick.
    Then again, a 1 km object would probably not be seen in time to anything about it.
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