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New NASA Maps Show A Bad Day On Earth
Stephen Lau writes "ScienceDaily has an article talking about the new NASA maps that reveal the geography of the North American continent in amazing detail. One of the maps provides strong evidence of a 112 mile wide, 3000 foot deep impact crater which they believe was the comet/asteroid impact that killed the dinosaurs and more than 70% of Earth's living species 65 million years ago."
Finally something people can "grab ahold of" out of NASA. If they made a bigger deal out of a lot of their other advances and discoveries they would be held in better public esteem. But the public usually only pays attention when something bad happens.
Scientists believe the impact, which was centered just off the coast in the Caribbean, altered the subsurface rocks such that the overlying limestone sediments, which formed later and erode very easily, would preferentially erode on the vicinity of the crater rim.
Wait. So nothing's really changed. So they are basically still saying that the Gulf of Mexico is the "real" meteor crash site and not this dimple... Hmmm... let's see, let's keep reading:
This formed the trough as well as numerous sinkholes (called cenotes) which are visible as small circular depressions.
Ummm... yup. This is a sink-hole, a dimple in the earth caused by the sudden crash/explosion NEAR BY. This is not the crash site. I wish people would read the damn articles before even submitting them to the editors (and that opens another can of worms there, but I digress...).
I'm not a prophet or a stone-age man,
I'm just a mortal with potential of a super man.
It's the media that adds the "this killed the dinosaurs" hype to it. They merely find evidence of collisions, but it's near impossible to accurately date them.
If they could date a crater with reasonable accuracy, then they could say more concretely that "This crater was formed by a meteor at about the same time dinosaurs went extinct, and the impact could have been sufficient to cause their extinction"
Many of the craters probably predate all life on earth. Maybe one of em is the one that split off the big chunk of rock that we call the Moon now.
But anyone who's saying matter-of-factly what happened, isn't acting like a scientist.
I don't need no instructions to know how to rock!!!!
> how do they know that this *particular* asteroid
> wiped out most of the species on the planet 65
> million years ago?
obviously they can't, with irrefutable "ah-ha this is it!" evidence. However they can narrow down the range of options for a specific candidate with things like core samples.
when an asteroid hits, it reorders the earth around it in some fairly identifiable ways. I don't know all the specifics, but it is rather common for geologists to date asteroid impacts by analyzing not just the dirt above the old crater, but the dirt below it too.
For example, if you take a core sample from a known undisturbed part of the planet, and identify at what age any specific depth was the surface of the earth, you can compare this sample to a sample taken from a suspected asteroid impact crater and date it that way.
Under the impact crater, there will be undisturbed material (fossils, stones, etc). Above it will be a messy jumble of everything, from bits of glass formed in the heat of the impact, to shattered rocks, a complete reordering of dirt layers.. stuff like that.
if you can link an event in earth's history (eg, dinosaurs going extinct) to the timeline a core sample reveals, you can get a pretty good guess for what the cause of the event was.
If the mass of humanity was killed, and you survived, wouldn't you seek the company and assistance of others? In the wake of tremendous destruction, what purpose would violence have? Cooperation would seem infinitely more important.
Sure, in a riot people are violent. But a riot involves people doing things they can't normally do in their lives amidst their society. It's a temporary state, almost by definition.
In a war people are violent, often long after the war. But that's more than just the collapse of society, that's an extension of society's self-destruction. Few apocolyptic scenarios involve mass societal collapse as a cause, unless the apocolypse is somehow based on everyone being turned crazy by Radio Waves From Space or something (very Steven King-like). In that case you wouldn't want a gun, because you'd kill someone you love or some other horror.
It'd look real silly if the survivors of an apocolypse were toting around guns in an empty landscape.