A team of researchers from Rensselaer Institute have accidentally discovered a real evidence of a comet strike that happened about 56 million years ago. This collision may have triggered an ancient global warming period called Paleocene-Eocene Thermal Maximum (PETM). The scientists say that deep investigation of the matter may help them understand the global warming we’re experiencing these years.
The connection between PETM and the comet strike was established after glass spherules were found in the rock core samples. These tiny spheres are also called microtektites and considered the comet debris left after the collision.
Such spherules are actually molten rock drops that froze after the comet collided into the planet. One more evidence of their origin is that they are a form of quartz, and a rock takes this form when tremendous pressure is put on it. The impact of an extraterrestrial object with the surface on a high speed qualifies the best in this case.
The scientists were busy searching for the fossils of small organisms when microtektites drew their attention. By conducting a deeper research, it was discovered that the sample contained 3 spherules per gram. The sediments were taken from three places along the Atlantic coast.
This discovery became the first ever physical evidence of the comet collision that happened 56 million years ago. Scientists of different times suggested such an event, but it couldn’t be proved before the leftovers were found. The particles of the comet are extremely small, as most of the material evaporates due to the high temperatures and the air flow that any space body faces when heading through the Earth atmosphere.
The Connection Between the Collision and Ancient Global Warming
56 million years ago the temperature on the Earth rose by 14 degrees Fahrenheit, leaving millions of microorganism species dead, and shedding ice-caps away from the poles. It became one of the most massive ancient global warming events, having a huge amount of carbon dioxide emitted into the planet’s atmosphere.
The comet was considered to have slammed into the Earth’s surface approximately at the same time, and this event has a physical evidence now. Such a strong collision may have triggered heavy earthquakes up to 10th magnitude, releasing considerable storages of methane that was hidden deep in the oceans.
The earthquakes may have become the reason for massive volcano eruptions that increased the carbon dioxide level of the atmosphere dramatically. Methane and carbon dioxide are greenhouse gases, which means they absorb the Sun’s heat and thus warm the atmosphere. The excess of these gases lead to the greenhouse effect, causing global warming.
The research of the microtektites is going on, and it can become a major progress in the understanding of the history of global warming. The comet collision was always just a theory, and the PETM origins were a sort of mystery. It makes this research even more important for learning about this ancient global warming, its impact on the modern Earth climate, and the reasons of the climate situation we have to cope with nowadays.