Various speculations.
In 1969, the American Apollo 11 successfully landed on the moon and brought back to Earth some rocks collected on the surface of the moon.
This discovery confirmed scientists' speculation, so since then, the focus of scientists' research has been on the planet.
Since the 90s, scientists have come to the conclusion that the space around the Earth has changed dramatically since 233 million BC, through a large amount of data analysis.
At that time, there was a planet about the same size as the Earth around the Earth, and later the planet passed by the Earth, shifting the Earth's axis by 20 degrees, so at that time, the Earth's poles were facing the Sun, and the equator was pointing to space.
The snow and ice in the snow-capped mountains began to melt under the sun's rays, which led to a sharp drop in temperature, forming the ice age of that era, and similarly, the decline of life on the earth.
In the process, the Earth's orbit has been disrupted by the striking planets, which caused the direction of the Earth's rotation around the Sun to change, changing the Earth's state from a polar state to a polar state, so that the Earth began to have a significant seasonal change, and the temperature difference between day and night became larger and larger.
In the reflected light from the sun shining on the earth, oxygen ions and oxygen atoms rub against each other, resulting in a phenomenon similar to "static electricity", which causes oxygen to be decomposed into oxygen ions and oxygen atoms.
In the air, oxygen atoms and ions begin to chemically react with surrounding molecules and atoms, forming layers of oxygen ions, which continue to increase in the atmosphere, resulting in increasing air pressure.
In the case of a gradual increase in air pressure, the earth's atmosphere gradually becomes a shield, which can play a role in blocking foreign meteorites, so as to achieve the intrusion of foreign materials.
Before 233 million BC, there was a lot of carbon dioxide in the Earth's atmosphere, and this material would play a protective role in the Earth's atmosphere, which could lower the temperature on Earth.
During that time, the vegetation flourished and the animals lived happily ever after, however, 233 million years ago, a major event suddenly happened to the Earth, and that was an asteroid that flew to the Earth.
Causes of heavy rain.
Above the Earth, there is an overwhelming wall of atmosphere.
When the planet hits the Earth, it causes a very big impact, in this case, the atmospheric wall is damaged, and the atmospheric pressure before the impact also emits some rain, and because at that time, there is a lot of carbon dioxide in the atmosphere, so there is also some carbon dioxide in this rain, which leads to the cause of heavy rain.
And after the planet fell to the earth, because of friction, it will also produce a certain amount of heat, and the gases in the atmosphere are affected by high temperatures, and these gases have become warm and moist air, so that a large rain is formed, and the atmospheric wall has also become very fragile because of the destruction, so 233 million years ago, the destroyed atmospheric wall has not recovered, and it has been injured twice, so this process takes a very long time, about more than 1 million years.
And the rain that fell in this heavy rain eventually flowed into the ocean, diluting the salt in the ocean, thus protecting the original seawater, which was rich in biological elements, thus creating conditions for the reproduction of later organisms.
After verification, this heavy rain has lasted for a million years, and this heavy rain has also had a great impact on the earth's environment, the most intuitive is that after the heavy rain, the amount of carbon dioxide in the earth's atmosphere has changed greatly.
And the weight of carbon dioxide in the air is relatively large, so when it rains, it will be carried to the ground, resulting in a lot of carbon dioxide levels on the ground, and the lack of carbon dioxide in the plants on the ground has hindered the reproduction of plant organisms, so that the animals are on the verge of starvation.
epilogue
Later, through the determination of fossils, scientists concluded that there was indeed a large-scale extinction event before 233 million BC, and after that, it was the "rebirth" of Cenozoic organisms.
Although this idea has not been finally accepted by scientists, there are many unknowns waiting to be explored in the field of science, so scientists are also open to new ideas.