The last worldwide extinction event was 65 million years ago, and scientists are wondering when the next one will be.
Somewhere deep down in space there is a massive stone, and he is targeting Earth. As we reported recently, the B612 Foundation, a group of scientists and astronomers, says the planet is vulnerable to a life-threatening strike, but it's worth looking at the amazing story of asteroids on our planet to understand the threat is ahead of us.
Five years ago, a 20-meter-wide asteroid injured more than 1,000 people and damaged thousands of buildings in Russia. Compare that to the Chicxulub Crater, which scientists believe was caused by an asteroid or comet 1
The Cretaceous-Paleogene extinction, as it is known among scientists perhaps the most famous of the "Big 5". The fourth was the Triassic-Jurassic extinction 199 to 214 million years ago, possibly due to an asteroid impact. The third was the worst in Earth's history, and it was lost 251 million years ago with 96 percent of species lost. This was probably caused by a huge volcanic eruption.
The second extinction, probably caused by volcanic ash, was the late extinction of extinction, which destroyed 75 percent of the species about 364 million years ago. And the first big extinction, the Ordovician-Silurian extinction 439 million years ago, killed 86 percent of life on Earth. This was most likely caused by icing and sinking sea levels.
So the question is not again whether a mass extinction will take place in the future, but when. And since an asteroid is the most likely cause, this explains why the B612 Foundation spends much of its time dealing with the challenge of our species.
The following is an explanation of the B612 website for their mission
B612 is an organization committed to protecting the earth from asteroid impacts and informing and passing on global decisions on planetary defense issues. B612 provides a non-governmental voice on the risks, options and implications of asteroid data, while further developing the technical means by which that data is obtained. We work to interpret asteroid data openly and accessible, serving as an informed source for an international community of politicians and scientists who can best contribute to achieving these goals.
B612 is an organization committed to protecting the Earth from asteroid impacts and informing and relaying world decisions on planetary defense issues. B612 provides a non-governmental voice on the risks, options and implications of asteroid data, while further developing the technical means by which that data is obtained. We work to interpret asteroid data openly and accessible, serving as an informed source for an international community of policy makers and scientists who can best contribute to achieving these goals.
Our expanded team of employees, employees and partners combined are the best and are incomparable in their expertise. The success of our work depends on it.
We believe it is our responsibility to use our knowledge and expertise to work for the betterment of humanity.
We are driven by the thirst for knowledge. Our commitment to discovery is fueled by a sense of wonderment for the universe and our evolving ability to explore it.
Initiative SeparatorWe believe that we can master and address unfulfilled challenges. We do not believe in wanting the best, but instead researching and developing solutions with the best results.
Whether you are a student, citizen scientist, or C-level executive, we need your help to support the cause and spread the word.
Our Asteroid Institute is a B612 program that works with major institutions around the world working on asteroid projects such as research, science, and technology. Our leadership drives strategy and operations, and the board oversees our long-term vision. Our founding circle, the asteroid circle and the worldwide community of donors make our work possible.
The following is an excerpt from Wikipedia about the last major extinction event of an asteroid.
The Cretaceous-Paleogene (K-Pg) extinction event, also known as the Cretaceous-Tertiary (KT) extinction, was a sudden mass extinction of about three quarters of the plant and animal species on Earth, about 66 million years ago , Except for some ectothermal species such as leatherback turtles and crocodiles, no tetrapods weighing more than 25 kilograms survived. It marked the end of the Cretaceous, and thus the entire Mesozoic, opening the Cenozoic, which continues to this day.
In the geological record, the K-Pg event is characterized by a thin layer of sediment known as K-Pg. Pg limit, which can be found all over the world in marine and terrestrial rocks. The boundary clay shows high levels of metal iridium, which is rare in the earth's crust but abundant in asteroids.
As originally proposed in 1980 by a team of scientists led by Luis Alvarez and Walter Alvarez, it is now commonly thought that the K-Pg extinction by the impact of a 10 to 15 km wide comet or asteroid 66 million years ago which destroyed the global environment, mainly due to a persistent winter impact that inhibited photosynthesis of plants and plankton. The impact hypothesis, also known as the Alvarez hypothesis, was supported by the discovery of the 180-kilometer-wide Chicxulub crater in the Gulf of Mexico in the early 1990s, which provided conclusive evidence for the K-Pg boundary clay represented by debris asteroid impact. The fact that the extinction occurred simultaneously provides strong evidence that they were caused by the asteroid. A 2016 drill project in the Chicxulub summit ring confirmed that within a few minutes, the gypsum ring consisted of granite that had been deeply ejected into the ground and contained little gypsum, the usual sulphate-rich seabed rocks in the region: it would have vaporized and scattered an aerosol into the atmosphere, the longer-term impact on the climate and the food chain.