[HN Gopher] Accounting for violent conflict risk in planetary de...
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Accounting for violent conflict risk in planetary defense decisions
(2020)
Author : pmoriarty
Score : 62 points
Date : 2022-03-11 15:27 UTC (7 hours ago)
(HTM) web link (gcrinstitute.org)
(TXT) w3m dump (gcrinstitute.org)
| TxProgrammer wrote:
| 'Chapman describes a "giggle factor" and a "Chicken Little"
| dynamic. That was ultimately changed by a mix of scientific
| progress, policy outreach, writing for the general public, and
| the major Hollywood films Armageddon and Deep Impact'
|
| -Good to hear that Armageddon may actually have done something
| good then..
| powerset wrote:
| You might even say they had a positive impact
| pc86 wrote:
| You might, but probably shouldn't :)
| perihelions wrote:
| Tangentially, Carl Sagan wrote a column (one of the earliest?)
| identifying asteroid defense as an existential risk:
|
| https://sci-hub.se/https://doi.org/10.1038/368501a0 ( _" Dangers
| of Asteroid Deflection"_, Carl Sagan & Steven Ostro)
| stevenwoo wrote:
| This is slightly expanded in Pale Blue Dot, though maybe half
| of the rest of the book serves as an interesting comparison of
| what Sagan thought might happen and what actually happened with
| space missions that were not complete at the time of book
| publication. Disappointingly, the audio book only has portions
| narrated by Sagan probably due to his cancer.
| not2b wrote:
| It seems that you always want to use deflection, despite what
| they did in the movies, and it is doubtful whether a nuclear
| explosion would be better than attaching something to the object
| and generating enough thrust to alter its path, possibly using
| some of the mass of the object itself (stupid way: land a
| trebuchet, toss enough rocks into space to move it).
| dboreham wrote:
| The nuclear weapon is a very high power trebuchet.
| perihelions wrote:
| Nuclear detonations would also use the mass of the object
| itself. The short radiation pulse ablates material off of the
| surface, and that's what provides most of the impulse.
| Vaporized rock is the reaction mass.
| AnimalMuppet wrote:
| I wonder. Is ablation better than having the warhead in the
| center of some mass, detonating the warhead to drive some of
| the mass at very high velocity into the target?
| lazide wrote:
| Considering that any mass as part of the launch vehicle
| will have a major trade off in time to intercept?
|
| It's way better to use the asteroid or comet itself. Every
| bit of mass (or second of delay to launch) you add to the
| intercept vehicle allows the bolide to get that much
| closer, requiring that much more escalating delta-v be
| added to it to clear the planet in time.
|
| If the object is caught and intercepted far away, it may
| take only the slightest nudge. Up close and personal, it
| might require almost vaporizing it.
| ravi-delia wrote:
| I think in terms of force:mass you can't beat nukes. We know
| how to make them, we know how to put them on rockets, and we
| can can line them up to detonate a little away from the
| asteroid, while a landing would need to match velocity.
| Probably the best would be nuclear shaped charges a la Project
| Casaba-Howitzer, which I believe were initially explored as a
| vehicle propellant.
| JumpCrisscross wrote:
| > _when an [_ sic _] NEO collision on Earth is mistaken for a
| violent attack, prompting an actual attack that the attacker
| believes to be a retaliation but is in fact a first strike_
|
| Oof, never thought about this one. Do we have systems in place
| that would quickly and reliably differentiate an unexpected
| asteroid impact from a nuclear strike?
| beojan wrote:
| > > an [sic] NEO
|
| That's perfectly correct grammatically. It just means whoever
| wrote that pronounces it N-E-O rather than "neo".
|
| As to your question, I think yes since I expect the trajectory
| would be very different.
| lazide wrote:
| Nuke strikes have a distinctive double flash that I don't think
| asteroids or meteorites do.
|
| I think they're more referring to 'if an asteroid hits
| Washington DC, Moscow, or Beijing in the middle of what is
| going on now, will everyone check their satellites for it
| before they launch a retaliatory strike?
| JumpCrisscross wrote:
| > _Nuke strikes have a distinctive double flash that I don't
| think asteroids or meteorites do_
|
| The concern raised in the paper, which I now share, is that
| in the time between initial detection and someone running the
| tape to count the flashes, nukes could be launched.
| Particularly for powers who have invested heavily in use-it-
| or-lose-it land-based missiles. You need that differentiating
| infrastructure and protocol in place _ex ante_ if it 's going
| to prevent false retaliation.
| Melatonic wrote:
| This is one of the functions of the new James Webb telescope
| right? From what I remember planetary defence was one of the few
| recent things a lot of countries agreed upon to mutually fund as
| well
| adolph wrote:
| I think the JWST is to far-sighted to be very useful for
| spotting something in an Earth intercept orbit. For one, it is
| to the outside of Earth's orbit and its instruments work in
| infrared bands requiring extreme cooling--it can't be aimed at
| angles towards Earth's orbit because of solar radiation. The
| shield at the "bottom" of the telescope allows for some
| inclination but not a tremendous amount.
|
| https://webb.nasa.gov/content/about/orbit.html
| marcosdumay wrote:
| Hum... I don't think anybody expects objects on an orbit near
| or more internal than the Earth's one to intercept us. The
| Solar System is quite old, and any nearby object would have
| already hit us.
|
| All the remaining objects that can intercept us stay far away
| most of the time.
| shlurpy wrote:
| No, it can watch asteroids, kupier belt objects, etc. Sure,
| not ones already near earth orbit, but most objects are
| further out at least at some point.
|
| However as far as I know it's unlikely to actively survey
| them. It's expensive and limited time, so it'd focus will be
| on what can only be seen in infrared, like the early universe
| and exoplanet spectra. But who knows what the scientists will
| decide look at.
| Beldin wrote:
| I think (you read it here first) that the first step towards
| actual planetary defense will be the moon. That is: humanity's
| first, actual, somewhat working system realistically able to
| defeat an incoming asteroid will consist of moving the moon. Not
| that that is easy - absolutely not. But it is genuinely something
| that we can prepare for. We can start building an infrastructure
| on the moon for vaporising moon rocks, providing thrust. Energy
| can come from sunlight. You could well argue that moving the moon
| is nigh impossible. It probably is. But it is (1) feasible and
| (2) an engineering challenge. The most daunting one ever faced by
| humanity, but the pay off is equally great: we get to save the
| planet.
|
| The key point is that the moon can easily stop incoming
| asteroids. It reduces the entire problem to "simply" moving the
| moon. Which is something I think is achievable with roughly
| today's tech.
| GoodJokes wrote:
| steve76 wrote:
| motohagiography wrote:
| Arguably, the best strategy for mitigating existential risk and
| responding to a NEO collision event is a diversity of
| populations, civilizations, economies, and governance on the
| planet, so that as a species we are more resilliant to such an
| event takes out one or some of us.
|
| Proposals that end in creating a single planetary policy source,
| and single global coordination and governance scheme to "fight"
| it necessarily reduce to dumbness because they create an
| economics that optimizes for reinforcing it over the interests
| and aggregate desires of individual organisms. Removing the
| diversity of governance alternatives means you have to optimize
| for that single solution, which in any complex system is
| essentially risk convergence, collapse, and death.
|
| We are much more likely to die off of a confluence of starvation,
| war, disease, and non-replacement birth rates wrought by the risk
| correlation of central policymaking before a meteor hits or some
| other global catastrophe is actually realized. It's so much
| easier to make humans fear the same thing than to get us to all
| believe in it, and once you get your hand on that lever, does it
| matter what the threat is? The lever is narrative. I'd be
| skeptical of people indexed on planetary defense, because it's
| just a proxy and pretext for another centralization agenda. Just
| like when everyone is responsible, nobody is - when a solution is
| for everyone, it's pretty much also guaranteed to be for almost
| nobody as well.
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