Asteroid hits theory gains traction

Fighting back To avert a repeat of mass-extinction asteroid hits on Earth, advanced countries are trying to develop ways of deflecting them off course or splitting them into smaller pieces. AFP

A 12-year-old theory that a giant asteroid hit the Earth 12,800 year ago and caused mass extinction, including saber-tooth cats, giant sloths, mastodons and mammoths is gaining renewed interest from research entities around the world, the Science Daily has reported.

Postulated as the Younger Dryas Impact Hypothesis, the theory proposed that the impact, surmised to have substantially reduced early human population, caused extreme environmental cooling ironically from the wildfires caused by the impact.

The fires produced so much smokes as to block sunlight and cool the Earth’s atmosphere during the close of the Pleistocene Epoch, according to the original theory now being backed by a new study published by the Scientific Reports.

Scientists led by archaeologist Christopher Moore presented evidence of a cosmic impact at the White Pond near Elgin in South Carolina through the discovery of platinum spikes associated with asteroids and comets.

The spikes had been found in North America, Western Asia, Chile and South Africa and Europe.

“There have been numerous papers that have come out in the past couple of years with similar data from other sites that almost universally support the notion that there was an extra-terrestrial impact or comet airburst that caused the Younger Dryas climate event,” Moore was quoted by the Science Daily.

“First, we thought it was a North American event, and then there was evidence in Europe and elsewhere that it was a Northern Hemisphere event. And now with the research in Chile and South Africa, it looks like it was probably a global event,” he added.

While another impact site in Greenland has yet to be dated, the scientists believe it and many other craters may be the “smoking gun” of a massive cosmic event like multiple asteroid hits that resulted to a brief return to ice-age conditions.

The hits had been hypothesized to have resulted to abrupt climate changes lasting 1,400 years, triggering mass extinction.

“It was bold in the sense that it was trying to answer a lot of really tough questions that people have been grappling with for a long time in a single blow,” said Moore.

“We speculate that the impact contributed to the extinction, but it wasn’t the only cause. Over hunting by humans almost certainly contributed, too, as did climate change,” Moore added.

“Some of these animals survived after the event, in some cases for centuries. But from the spore data at White Pond and elsewhere, it looks like some of them went extinct at the beginning of the Younger Dryas, probably as a result of the environmental disruption caused by impact-related wildfires and climate change.”