A 600-meter asteroid is big and would cause a lot of damage, but the one that killed off most dinosaurs was 37 to 58 kilometers across. A quick search on the 540 A.D. meteor shows some evidence in landed in the ocean near Greenland and caused the earth to cool by 3 degrees C, which is substantial. I’m glad you brought this up, Trucker. I hadn’t heard of this before.
Apparently this may not be the first time something like this happened.
This is the story of the meteor that changed the world forever. In 312 AD the Roman Emperor Constantine claimed he saw a mysterious light in the sky which convinced him to convert to Christianity, forever altering the course of history. Now scientists believe they may have tracked down the source of this mysterious light.
A team of geologists have identified a crater in Italy which they believe was produced by the impact of a previously unrecorded meteorite. The finding could explain not only the story of Constantine, but might also provide an explanation for a local legend which recounts how members of a pagan cult were overwhelmed by a light in the sky as bright as a second sun. The cult too immediately converted to Christianity. A team of international experts set out to get to the bottom of the mystery.
I stumbled across the first video the other day, posted in on another site, and someone there added the info about Constantine. Coincidentally enough, I’m rereading Bible Myths and Their Parallels in Other Religions by TW Doane, and he speculates that the origins of the Flood myth might date back to around the end of the last ice age. (Bear in mind, this book was written in the late 1880s, so there wasn’t nearly as much known about the world’s climate in ancient times.) And we have some evidence that animals like the woolly mammoth were wiped out by a comet strike around that time. All of which makes me wonder how much influence cometary impacts have had on human society.
I would think that it’d be in the early years of its life (at least as a comet) that Halley’s Comet would be most likely to shed large hunks of itself off as it flew by. The earliest recorded sighting of what is believed to be Halley’s Comet, at least according to Wikipedia, is 467 BC, so it may not be that. But it would be interesting to see what the climate was like around that time, and if there were any sudden changes to it. I know rock carvings turn up from time to time showing ancient celestial events, those might have clues as well.