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Assume you and I are prehistoric people who have no idea the Earth is round. We are both at the equator, but separated from each other by a couple of thousand miles along it, and we decide to do an 'experiment'. We both head due North, and after several hundred miles of travel, we notice that our lateral distance has decreased considerably. The farther north we travel, the faster our lateral distance decreases, until finally, at a place with the signpost "North Pole", we crash into each other. So what do we conclude from our 'experiment' ? Some mysterious 'force' seems to be drawing us together, and this 'force' seems to act without any connection between us. Now all this is due to the fact that prehistoric peoples didn't know they were living on a curved surface. We present day people, know the Earth's surface is curved, so we don't come to such foolish conclusions. But what if it isn't just two dimensional surfaces that can be curved; what if both space and time comprise a manifold that can be 'warped' or curved by the configuration of the energy contained within it, whether that energy is in the form of mass, momentum, stress, or even pressure. It seems some of us are still foolish enough to make those assumptions, and wonder what is connecting the two bodies drawn toward each other, when the 'path' ( known as a geodesic ) is simply constrained to the 'lay' of the land ( known as a 4 dimensional space-time manifold )

I'm with Airbrush on this and think nuclear devices delivered by variants of existing rockets would be the preferred means, probably the only one possible any time soon. Longer term - and I do think meteor defense is best viewed as long term - other options may become possible. Delivered and it is done versus delivered and just getting started. Much more deflection from less payload. Shorter mission times. Uses familiar technologies with lots of existing knowhow and capability. The links people have provided, including yours appear to support that although different asteroid examples and different units make direct comparisons a bit tricky - at least for me. https://arxiv.org/pdf/physics/0608157 with Apophis (320m diameter, 46 million metric tons) as example for a 1 ton gravity tractor - 3.7mm per sec per year (? Someone else should check units and arithmetic?) https://ntrs.nasa.gov/api/citations/20205008370/downloads/Nuclear_Devices_for_Planetary_Defense_ASCEND_2020_FINAL_2020-10-02.pdf with 560m diameter object and 550kg payload - 65 to 165mm per sec in a few seconds to minutes with a single 1 megaton nuclear device for a significantly larger object. Having the device stationary with respect to the asteroid seems to be preferred over one coming at it at high velocity but not sure how that would work directly along the trajectory.They look to smaller than 1 Mt explosions as preferred - several small ones better than one bigger one. Spinning object? Having a quick search for rotation rates - it sounds like a large rubble pile would max out at 1/4 rotation per hour, slow enough for a nuclear detonation to give directional push. Small ones would be suitable for dispersing blasts. Too close to Earth? The "nuclear devices" paper deems several months of warning as a short warning, late response scenario and doing the detonations more than a month out from expected impact is considered a rapid response. I can't see that as an EMP risk to Earth that far out. Anything as close as the moon will be days at most away - too late, kiss arses bye bye. Nukes not designed for use in space? I expect some probably are even if that isn't advertised; the potential for nuclear warfare to happen in space has been known a long time; it may be against arms agreements to put any into space but military planners always look beyond existing treaties if only on an Irish basis - to be sure, to be sure.

"No, no, I said I wanted 'room to rest' on every landing!"

Why do you ask?

! Moderator Note Since you seem to be adamant about ignoring corrections to your flawed descriptions, this is closed. Do not bring the topic up again.

Just something I found on Wikipedia... https://en.wikipedia.org/wiki/Asteroid_impact_avoidance#:~:text=An object with a high,a spacecraft with the asteroid.

Use the equation of state for a scalar field. The FLRW metric version is a good starting point. https://en.m.wikipedia.org/wiki/Equation_of_state_(cosmology) We already have equations to describe vacuum fluctuations with a pressure term see link. Under GR the stress energy momentum tensor has the pressure terms. This will correspond to how pressure is handled under QFT

My NB was in regard to the current arsenals, which were suggested as providing the charges for these hypothetical asteroid deflectors. Am aware of the bad old days of multi-MT blasts. A close relative lived most of his life a couple miles from the nation's foremost nuclear bomber base, and I used to live uncomfortably close to StratCom hq, so have been fairly aware of the arms race history and living in the crosshairs. The main problem with Castle Bravo or Tsar Bomba sized bombs, as mentioned in a following post, is difficulty in delivery of such massive weapons to a target. My reading of this discussion so far is that a smaller charge is easier to deliver to an asteroid, provided you have enough lead time to strike it at a great distance and thus gain the required deflection with less force.

There would not be a shock wave. It would be just an intense, short pulse of heat. ChatGPT says: "The distance of the explosion from the asteroid and the yield of the nuclear device would be crucial. For rock fusion to occur, the heat and energy must be sufficient to melt the surface material. If the explosion is too far or the yield is too low, the energy might dissipate without causing significant melting." "In theory, a nuclear explosion could cause surface melting and outgassing, potentially pushing a "rubble pile" asteroid. However, the practical implementation of such a strategy would require precise control over the explosion's distance and yield, careful consideration of the asteroid's composition and structure, and strategies to mitigate the risk of fragmentation. More research and testing would be necessary to evaluate the feasibility and safety of such an approach."

Most important metric ... Where would you rather live ? And if your answer is China, I will gladly start a crowd fund to buy you a one way ticket.

Some early radio telescopes were built by amateurs, though they were very dedicated amateurs https://en.m.wikipedia.org/wiki/Grote_Reber (an astronomer friend at work made me aware of Grote Reber, and several of us agreed that the reber should be the unit of effort put into any hobby. Most of us would register millirebers)

I did not know about carborane acid. Rather interesting. Thanks for drawing to my attention.

Why would such a warhead be used as an example here? Who has 100 megaton warheads? Who is capable of delivering a 100 megaton warhead? Why is the orbit of the moon being used as an limit? If all we would get is a minor effect why bring this up at all? This example is nothing but fear mongering, if you wait until an object is within the orbit of the moon you are up the creek, such an object is just hours, possibly minutes from impact at that point, do the math! Why keep using these exaggerated examples instead of realistic scenarios? We need to plan ahead, get the infrastructure in pace before the threat looms over us but until that infrastructure is in place the easiest and fastest method should be used. Nuclear warheads delivered to the target via existing technology as far from us as possible would seem to be the best option we currently have. An asteroid impact is a serious event quite possibly apocalyptic anything other than our best efforts is suicide. Exaggerating the danger of nuclear technology does not serve us.

You made he claim that a nuke detonated inside the the moons orbit would cause a damaging EMP pulse on the earth, then you equivacated and said it would have to be a 100 megaton nuke which no one has ever detonated much less currently have. I suggested a 250 meter asteroid, Apophis is over 300 meters if memory serves me. The asteroid that killed off the dinosaurs was several kilometers in diameter if such a asteroid threatened us now days we would be screwed AFAIK there is no way to deflect such an asteroid in any reasonable time frame so why do you try to use it as an example? More fear mongering? Why?

One thing you don't have for sure is the desire to discuss this in a non emotional way.

No, you used the EMP thing as an example of how dangerous the nukes were, in that context you were not being accurate and in fact deceptive so no your assertion was not valid. In fact your idea of stopping the asteroid as it hits the atmosphere with a 100 megaton warhead is not valid, can you use physics and math to understand why? Your exaggerated assertions about the danger of fall out from the detonation of a nuke were not valid. You go be you dude... I'll stick with arguing reality.

Again you sad the effect would not be significant not me. That is why what you asserted was deceptive, you tried to convince us the EMP from the moons orbit would be dangerous to the earth in some significant way, then when called out on it you admitted the effect would be minimal and not dangerous. That is deception. I have no doubt that such an important experiment could be approved if proposed by the proper authorities.

You are exaggerating the risks to further your agenda, I simply seek to mitigate the actual risk potential to further the safety of the human species. Your assertions about the EMP near the moon I think confirm my suspicions. Your example of the Chicxulub impact just shows you are not interested in an actual discussion.

I can see that shock still did not wear off. Mathematicians are extremely good at what they do ,but in my humble opinion they do need to take extra courses in geometry ,vectors and a fluid mechanics . Here is something funny,I hope not that offensive for mathematicians