Asteroid crater 520km in diameter buried in southeast Australia, scientists say

As someone who reads a lot in general and on the topic of space in particular, I am surprised to only discover this word today. I suspect that it is not a common word, or maybe it is a new word.

Sure, milliseconds before impact the atmosphere might be super-compressed (and super-heated). Perhaps even exert considerable force. But compared with kinetic energy of that size impactor, at such speed: negligable.

Small objects 'feel' the atmosphere much stronger. Surface area vs. volume.

A column of air weighs ~1kg/cm^2 (handy!), and the example has a 15km span of "Dense Rock" which I've seen mean "Dense Rock Equivalent" in the Volcanic Explosivity Index, where it has a density of 2,500 kg/m^3. Assuming that, a column of the asteroid is

2500kg/cm^2/(100cm/m * 100cm/m) = .25kg/m * 15km = 3,750kg

The kinetic energy per column of the impactor is 1/2mv^2, or 0.5 * 3750 * 80000m/s^2, or

1875 * 6.4e9m^2/s^2 = 1.2e13 Joules

Which is about 20 gallons of gasoline equivalent. As you say, that's absorbed in ~1s (space is 100km up, so 80km/s is just about right). If so that warms up and starts melting the surface of the asteroid, but not much more I guess.

So 30km down it would be hitting liquid rock and a lot of heat.

1. https://arxiv.org/abs/1804.03748

But now after being exposed to the true collective nature of mankind, it doesn’t matter. This species is a net negative for the universe. Just a bunch of monkeys squabbling over stupid things.

Paradoxically, "survival" assumes adapting to ever-changing circumstances, which means that homo sapiens, given enough time, is bound to evolve into one or multiple new species given enough time. Regardless of that happening elsewhere or on Earth.

Arguably, a species is just a mode of survival for a genome; a convenient vessel through time as the genome reproduces. The language we use is, ultimately, a social construct, but biological speaking by and large inconsequential in so far that language is a trait that fosters survival. Evolution isn't opinionated, it just 'is'.

The fate of the Neanderthal people feels apt here. While the species is extinct, our Sapiens genome still caries 1-4% of Neanderthal genes to date. Some of that influences traits in modern humans, some of that just doesn't. (Evolution is messy, in that regard) Now, maybe Neanderthals wondered - just like us today - what would become of them aeons in the future. Little did they know that we, Sapiens, are distant relatives to them.

In the same vain, our written record and collective memories spanning no longer then a few millennia, distant relatives in the far future may look back at our detritus in the soil and in their genes and maybe wonder the exact same thing.

Maybe the Great Filter isn't some civilization destroying event. Maybe it's just evolution. Maybe become a space-faring species might be the biggest mistake we could make. I think more then a few sci-fi authors coined the notion of the arrival of malevolent alien species in a distant future which turned out to be our distant relatives from space-faring humans who left Earth eons ago. Of course, that's just speculation. But there's some poetic food for thought there, it's a probability one can't readily exclude.

There's data out there about the First Ancestral Race but AFAIK they've never released the unredacted version of the Secret Dead Sea Scrolls, so it's hard for the public to say.

It's seems like a pedantic distinction, but it's important. Earth doesn't care if we're here or not. The universe doesn't care if we're here or not. We are the only ones who should care, and we seem not to.

The planet will be fine, eventually, after we die out. Life will continue after we're long gone.

But we'll be long gone, and it's like we've all decided that's okay.

In the grand scheme of things, I'm tempted to say: if that's the price to pay to expand beyond it, then so what? It's not like it's the only planet in the Universe.

People posting on web forums, especially engineers, like to poke holes in things and aren’t big into expansion and exploration at the moment. Probably a bit depressed from sitting in front of their computers all day too.

Ask someone who just spent a month on the pacific coast trail, or who is about to go to Antarctica the question, and you’ll get a different set of answers.

It actually correlates really well with the advent of teaching young children to be guilty about the civilization which gave birth to them. Maybe we shouldn't be slamming first graders with the ideas that everyone who came before them were supervillains and that they must shoulder the burden of correcting long dead injustices.

In any event, doesn't much matter. Every week there's a new article about how one nation or another has below-replacement fertility that doesn't seem to have any real prospect for reversing (tied to, more than anything else I think, what was described above). We are probably already a dying species, or at least heading into a post-civilization phase, and just don't know it yet.

I personally think that it's the most pragmatic view, if not the most rationale: with such an approach, only actions that are truly achievable retains attentions, if we try something, let's do the things that matters in the long run instead of trying literals shot in the stars.

Also, given the systematic and very damaging polarisation of all debates, I like being able to distance myself: it does not matter in the long run, so if the toxics annihilation has to happen, I won't be part of it, and it's probably the best I can actually do.