News! News! Another scientific discovery! This time is about a comet that could have drastically changed the climate on Earth thousand years ago. How do we know this? Because scientists have found some evidence in the depths of the ocean and this could be the key to solve one of the biggest mysteries in history on our planet’s climate. So, let’s learn more about this comet and its possible consequences on our planet.
Sudden return to ice
About 12,800 years ago, when the last Ice Age was ending, the Earth suddenly became colder again – the period known as the Younger Dryas. So, instead of becoming warmer, the climate drastically lowered for more than 1,000 years.
For decades, scientists thought this change was the consequence of the melting of huge glaciers in North America, altering the Atlantic currents. However, new evidence points to a much extraordinary event: the impact of a comet.
In the depths of the ocean
A team led by Christopher Moore analyzed sediment cores extracted from the bottom of the Baffin Bay, between Greenland and Canada. These cores are like time capsules: each layer shows what happened on Earth in a specific time. So, in the layers belonging to the beginning of the Younger Dryas, scientists found:
- Tiny metal particles.
- Glass-like spheres formed at very high temperatures.
- Platinum and iridium, elements often linked to space material.
The most surprising thing is that this is the first time they find these signs under the ocean. Until now, they were only seen on the ground, which generates many doubts on if they were from local fires or normal geological processes.
What the comet theory says
According to the Younger Dryas Impact Hypothesis, the Earth would have passed through the debris of a broken comet. Some of these fragments exploded on the atmosphere causing:
- Massive wildfires around the world.
- Thick clouds of dust and smoke that blocked sunlight.
- A sudden drop in global temperatures.
This phenomenon, called ‘’impact winter’’, would have blocked sunlight and provoked the sudden cooling of this period.
Consequences
The possible impact of the comet coincide with big changes on Earth like:
- Many large animals in North America went extinct, including the woolly mammoth, the saber-toothed cat, and giant ground sloths.
- The Clovis culture, one of the earliest human groups in North America, also disappeared during this period.
Some scientists believe these extinctions happened because of climate change provoked by the comet, whereas others think human hunting also had something to do here.
Importance of this discovery
For years, people against this comet hypothesis said there wasn’t strong evidence, arguing that the particles found on the ground could come from volcanoes or fires. However, finding the same remains under the ocean reinforces the idea of a global event.
Yet, there are some doubts about it. The main one is there haven’t been found a clear crater that could confirm the impact, that is why the debate is still going on. But the new study offers more convincing evidence every time.
Could this happen again?
Not only does this finding explain the past, but also reminds us that comets and asteroids still pass near Earth today. Even though the probabilities of a huge impact are low, even a small event could have serious effects on climate and human life. That’s why agencies like NASA are constantly watching out for objects near our planet.
So, next time you hear about a space mission or efforts to track asteroids and comets near Earth, remember this is to have a better understanding about the past which will help us protect the future.