How well would modern society handle the dinosaur killing meteor if it happened today?

Factual Questions
161

Energy equals momentum. Niven and Pournelle in assorted novels (i.e. The Mote in God’s Eye) suggested that a decent sized very light-weight sail spanning dozens or hundreds of kilometers could use the momentum from reflecting light from the sun or giant lasers to reach decently relativistic speeds,

The obvious solution to an orbital laser would be … wait for it… orbit. During half the orbit it blasts away at the target and is pushed faster in its orbit around earth. then as it comes around from behind the earth and starts blasting again, the same amount of momentum slows the laser down as much as it was sped up. the orbit just has to be in the same plane as the beam direction. Just don’t blast away while in front of the earth, or you will progressively push the perigee closer to the earth until reentry and rapid unplanned disassembly happens.

Again, the issue will be dissipating the left-over energy from firing the laser, since lasers are inherently inefficient. I think landing a large (LARGE!) number of ion engines and regularly refueling them would be the solution, given enough time. After all, given enough time, the deflection amount does not have to be large.

162

I don’t think so. For light. p=E/c. That is momentum equals the energy of the photons divided by the speed of light, a very large number, hence lots of light energy is very little momentum. Non-zero but “noticeable”? Enough to meaningfully impact the course of a very high mass space located laser station? So much that it would all that hard to correct for it?

163

Yeah, an asteroid-killing laser would produce some momentum, and it’d probably be enough that we’d need to account for it… but we can account for it, without too much difficulty. It wouldn’t be enough to cause any difficult-to-solve problems. To be sure, such a device would have 99 difficult-to-solve problems, but recoil ain’t one of them.

But it wouldn’t even be random. Humans are already clumped in some places, and there are also clumps of where, for one reason or another, people would be better prepared for the event. The entire nation of Iceland, for instance, would probably survive, unless the impact were close enough to obliterate them: Everything there is built to tolerate extreme cold, and they’ve got abundant geothermal power, and already use it to grow food.

164

I’m sure we can. If we can land a rover on Mars with such a complicated delivery system, then in building a giant space laser, we can compensate for the thrust of the laser.

However, we do need to make sure that we actually do. Just as we can compensate for the difference between English and Metric units, if we forget to do so, there can be consequences.

I don’t think it would be enough to be hard to deal with, but I do think it would be more than enough to throw off our aim if we don’t.

165

The nation that sits on top of one of Earth’s most active hotspots? I don’t fancy their chances much at all.

166

I thought I gave sufficient room for people to expand the answer when I wrote “which, if not massless, is nearly so”, while making my answer short and easy to understand.

I thought, someone may come by and say “As Melbourne suggested, transmission of light is not entirely without reaction, only nearly so.”

Alas, the tone of General Questions to frequently slides into ‘Great Debates’, with people looking for something to disagree with.

Reading my post, I find that I can’t apologize for it. Would it have really been more helpful if I had written ‘momentum’ instead of ‘mass’? Most of my friends never did high school physics. When writing about the reaction required to move a mile-wide meteor, is throwing a can of beer – or an aspirin – a substantive action? Most of my friends would say it ‘has no effect’.

I’m glad you’ve all taken the opportunity I deliberately threw open for you. I don’t think that making my own answer longer or denser would have been right.

167

FWIW it gave me an opportunity to reduce my ignorance, as I found the question of whether or not there would be noticeable/significant momentum to deal with, the question of where and how fast the presumably massive laser station would move due to recoil, to be interesting.

To answer precisely we need the mass of the station and knowledge of how powerful each pulse is how long each pulse and how many of them per unit time. But the answer is certainly in the not very significant albeit nonzero range.

168

Yes, that nation. It’s not like an impact would make every volcano on the planet erupt at once. It’ll certainly trigger volcanic activity at the point of impact, and might also trigger it at the antipodal point, but not elsewhere.

169

Yeah but it would increase volcanic activity over the next six hundred thousand years so they’re doomed! :slight_smile:

170

That’s highly debatable. Antipodal large-scale volcanism is the big effect, but any 15km impactor is going to make the whole planet ring like a bell, and in the K-Pg event, large scale seismicity triggered volcanism not just at the antipodes but also at other existing sites of magmatic activity. Specifically the mid-ocean ridges.

My, what island nation sits not just on a hotspot, but also a mid-ocean ridge?

Sarcasm coupled with lack of substantive reply duly noted. It’s amusing that you’re implying there’d be an impact, and then things only slowly ramp up over hundreds of thousands of years. The biggest effects will be a lot sooner than that, and then tail off.

171

You also need someplace that’s not on fire or under water. And it might be a really bad winter; as in, ten feet of snow on the roof, or even glaciers.

That’s not going to be any ordinary house.

There are certainly some already-existing bunkers. How many of the people who make it into them would be people emotionally stable enough to make it through their time in the bunker is another question – and bear in mind that one or two homicidal people per bunker might finish off everybody else in there. You need everybody in there to be able to stand up under extreme emotional stress – much less of a problem in previous bottlenecks, in which those in one group would have had no idea what had or hadn’t happened to everybody else.

Now arguing the other side: if enough of us for a breeding population make it 30-40 years, then I’d say we’d have quite a good chance of surviving as a species. Scattered groups of 10-100 with no travel except by foot and no developed infrastructure was how we started out, after all.

The problem is that almost nobody knows any longer how to stay alive like that; and there’s a whole lot that needs knowing in order to pull it off. Anybody who manages 40 years is going to have figured a lot of it out, however; and anywhere that people survived the first results of impact is going to have at least some tools and food also surviving in that area to give them a bit of a start.

If the asteroid’s big enough, I figure we’re toast. Exactly how big is big enough, I don’t know. And some of it might be pure chance: does a surviving group carrying essential genetics move into a radioactive area they didn’t know about? do they wind up in the same spot as somebody who’s decided God meant to kill us all off and they’re supposed to help that along? do they get hit by a tornado, and the ones who survive that include only one possible child-producer, who then dies in childbirth?

But in any case: “modern society” is gonna be gone.

172

I don’t know that traditional survival skills are going to be of that much use. Hunting and foraging won’t do you any good when the forests are all burned to a crisp and most of the animals are dead.

We will need to depend on technology to keep us alive, and it will be the skills to build and maintain that technology that will be necessary.

173

Moderating

Let’s avoid snark in this forum.

Colibri
General Questions Moderator

174

The substantive reply was given higher up in the thread, in which citations were provided that explained how the time course was NOT impact and immediate explosive volcanism, but, possibly, impact and apparently changes in currents that resulted in the Deccan Traps being sent into eruptive high gear, increasing volcanism to over its then extant high baseline for the next hundreds of thousands of years. Meanwhile other data exists that the big volcanic pulse that possibly contributed to the extinction event occurred tens of thousands of years before the impact.

Yes, I thought your response to the hundreds of thousands of years time course of

was meant to be a joke actually! (Not snark this, I did.)

Another post cited a model which demonstrates the limited immediate effect of such an impact in terms of ground displacement, tsunamis, and seismic and volcanic activity, was also cited.

So while you state with certainty and authority that the biggest effects would be “sooner” and “then tail off” but there is no apparent actual BASIS for that statement. In fact there is NO evidence of an immediate pulse in volcanism occurring at the time of impact or immediately after.
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Change of tack here …

Let’s imagine an impact to be is identified, determined to be one that would destroy all or most human life, and it is determined that there is no avoiding it. No fighting the hypothetical.

What are the alternatives to preserve modern humanity given many decades to develop some options? Given that such an option might be humanity’s only hope for survival as a species short of civilization being set back to HG or at least very early agricultural stages. Under such motivated conditions:

How far into the future is it to colonize Mars or another location in the solar system?

How far into the future is it to imagine creating a storage bank of embryos and seeds of humans and critical species with an AI able to monitor conditions (from space perhaps), landing, doing a few generations of planting autonomously, and then raising and educating a generation of humans (see Mother with a different trigger of the events, or even Raised by Wolves with an ark landing back on Earth)?

175

That’s a point.

Another point is that much of that knowledge is location-dependent; not just ‘how to find water’ but ‘where is the spring that doesn’t run dry.’ But in a disaster like that the spring that doesn’t run dry may well run dry, or have become fouled or inaccessible. ‘How to find water’ and ‘how to tell if it’s safe to drink’ are still going to matter, though – although techniques that depend on the presence of specific other species may not work.

We’d also have to figure out the other stuff; because we’d be unlikely to have the population levels needed to sustain the technology we’ve been using. Some technology, yes. We’ve needed some technology since we were Habilis, if not before.

176

I never said “immediately”, just “sooner [than all 600 000 years]”. I’m a geologist, though - “sooner” to me is still many thousands of years. Hell, so’s “instantly” .

Most of the mechanisms of seismic-triggered volcanism aren’t slow-burn effects. That’s what the most current thinking on this with regards to “ordinary” seismic-induced volcanism shows, never mind how compounded that would be by an event the size of a dinosaur-killer.

This is my take on it, too.

Then we’re dead. Modern technology is a pyramid, reliant on lots of people at the unconsidered base.

177

The proposed mechanism of possible impact induced increases in volcanism are not normal “ordinary” seismic-induced mechanisms compounded; it is a fundamental change in geothermal currents.

But here is the disconnect-

The only possible geologically “sooner” is the identified pulse in activity 10,000 years BEFORE impact. But hey let’s assume they’re wrong and it was 10,000 years after. As a hypothetical. A flipped sign!

Instant as that might be geologically, it is a long long time for human development. 10,000 years ago was pre pottery Neolithic with most of humanity scattered HG and a few larger settlements in the Fertile Crescent. Cultivation of grains was soon to spread out but has not yet.

Multiple human civilizations rose and fell in a geological blink.

Instant as that might be geologically it’s a long long long time compared to the expected length of any global winter.

(A geologic burp ago, 100,000 years, Homo sapiens were likely just starting the main modern dispersal migration out of Africa.)

Humanity will develop in unimaginable ways in the thousands of years that is a geological blink, assuming that we don’t drive our own extinction first. It won’t stay in one place geographically or technologically.

178

One factor is that IF enough animals survive that are worth hunting for their meat, any people surviving in the U.S. would have access to plenty of guns and ammo to hunt them with.

179

If there’s a full scale firestorm, wouldn’t that ammo mostly have gone off?

(Serious question; that’s an area in which I’ve got only minimal knowledge.)

180

That’s the mechanism for the antipodal melting. I’m saying you’ll see that and global “ordinary but upscaled” effects as well. That being the reason I’d want to be nowhere near any current active volcanism. Sure, it might not be set off. I don’t gamble.

Well, that’s just not true. I’ve already linked to one piece showing clear post-impact effects.

Yes, that’s what “bombed back into the Stone Age” means, whether it’s real bombs or a 15km rock.

Or is it your assertion that the bits of modern society that survive are just going to continue, only reduced in size? In which case - see my above post about pyramids.