Sentences with phrase «extraterrestrial impact»
The phrase "extraterrestrial impact" refers to a situation where something from outside of Earth, like a meteor or asteroid, collides with our planet. Full definition
At Wally's Beach, Alberta, a radiocarbon age of 10,980 purportedly dates extraterrestrial impact markers from sediment in the skull of an extinct horse.
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«Either there were many more impacts than supposed, including one as recently as 5 centuries ago, or, far more likely, these are not extraterrestrial impact markers.»
Extraterrestrial impacts ended the age of the dinosaurs.
Becker, along with two dozen — odd scientists, is studying a thin 12,900 - year - old geologic layer across North America that she believes holds the legacy of a major extraterrestrial impact roughly half the size of the one that killed the dinosaurs.
First, no matter how devastating an extraterrestrial impact might be, are we to believe that after centuries of flourishing every last tool, potsherd, article of clothing, and, presumably from an advanced civilization, writing, metallurgy and other technologies — not to mention trash — was erased?
To bolster the notion that rocks were beat up in an extraterrestrial impact, geologists search for a distinctive signature: microscopic bands in the mineral quartz, created when powerful pressure waves ripple through the rock.
But no one had studied the sediment record in enough detail to determine whether the animals and plants actually endured without variation prior to the extraterrestrial impact.
Therefore, the presence of shock features in quartz should not be taken as unequivocal evidence for an extraterrestrial impact.
First, fossil leaves and pollen excavated from the layers immediately below the K - T boundary show that the diversity of flowering plants substantially decreased in patches throughout the region before the extraterrestrial impact.
Most evidence for the extraterrestrial impact hypothesis, he says, was conjured up «out of thin air.»
The disappearance of these early Native American artifacts was apparently not due to an extraterrestrial impact.
Proposed causes have included everything from climate change and the spread of humans to virulent diseases and an extraterrestrial impact over eastern Canada.
One of the potential causes of the massive injection of carbon into the atmosphere during the PETM is an extraterrestrial impact on Earth.
The massive space rock — the first object to score above zero on the Torino hazard scale, which ranks the danger of an extraterrestrial impact — has about 1 chance in 500 of colliding with Earth in 2030, astronomers estimate.
The speed of the change makes an extraterrestrial impact the likely cause, they say.
Researchers have found apparent remnants of an extraterrestrial impact some 55 million years ago, in cores from three locations in southern New Jersey, and in a deep - seabed core off Bermuda.
Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling
The scientists believe that evidence for these extraterrestrial impacts is hidden in a dark layer of dirt sometimes called a black mat.
Schultz, professor of geological sciences at Brown and an impact specialist, said the most provocative evidence for an extraterrestrial impact was the discovery of nanodiamonds, microscopic bits of diamond formed only from the kind of intense pressure you'd get from a comet or meteorite slamming into the Earth.
Directly beneath the black mat, researchers found high concentrations of magnetic grains containing iridium, charcoal, soot, carbon spherules, glass - like carbon containing nanodiamonds and fullerenes packed with extraterrestrial helium — all of which are evidence for an extraterrestrial impact and the raging wildfires that might have followed.