This article is from WeChat official account:Bring science home (steamforkids), author: Shen mengxi, drawing from the head: “Mars rescue”
Imagine the Chinese Mars Rover Picture/Xinhua News Agency
This year is considered a climax year for Mars exploration. On July 20, the UAE’s Mars rover “Hope” was successfully launched, and China’s Mars rover “Tianwen No. 1” also successfully lifted off, a little later 7 On the 30th, the United States will also launch a Mars rover.
Following these Mars probes to the sky may be our curiosity: Is there life on Mars?
Here, my answer is: I will not be surprised at the emergence of life on Mars. I even think that the emergence of life on Mars is a high probability event.
1. The origin of life on earth
Before talking about life on Mars, we need to review the birth conditions and birth process of life on Earth. According to the current mainstream scientific theory, the earth was formed about 4.55 billion years ago. At that time, the sun was just born out of a cluster of nebula. 99% of the matter in the nebula gathered in the center of the nebula to form the sun, and the restNebula matter gradually forms the major planets in the solar system in the process of moving around the sun.[1].
In modern theory, the solar system is formed in a cluster of nebula map/network
The earth just formed is a hot magma ball, and then the earth cools rapidly. During the cooling process, chemical reactions occur in the magma, releasing a variety of gases, including a large amount of water vapor. After the magma on the surface consolidates to form rocks, the water vapor falls in the form of rainfall to low-lying places on the surface, which is the earliest ocean.
Early Ocean Imagination Picture/EGU Blog
As for when the earliest ocean appeared, scientists have not yet concluded. There is some evidence that the ocean may have existed 4.4 billion years ago, but because about 4 to 3.9 billion years ago, the solar system experienced once It is called the late heavy bombing event. In this heavy bombing, countless asteroids hit the earth. The surfaces of the moon, Mars and other planets we see today are densely packed with craters, and a large part of it is due to this. The late heavy bombing event wiped out the evidence of the ancient ocean and the possible existence of ancient life, and it is now difficult for us to study [2].
Picture of the Earth in the heavy bombing incident/NASA
Most of the craters on the surface of the moon came from heavy bombing events. Picture/Britannica
Meteor craters on the surface of Mercury Picture/NASA
After experiencing late heavy bombing events, about 3.9 billion years ago, the earth soon covered a large area of ocean. However, the sea water in this ocean is very different from today’s sea water. The first is minerals. The concentration of minerals in the ancient ocean was much higher than it is now. Maybe”data-w=”1080″ data-h=”766″>
Outflowing rivers on Mars[4]
The volcanoes on Mars are also very active in ancient times. Mount Olympus on Mars is a huge volcano. Its height reaches 21.9 kilometers, which is almost 2.5 times that of Mount Everest. It is currently the solar system. The highest mountain known within.
The largest volcano on Mars: Mount Olympus Photo/NASA
From the perspective of time, if the late heavy bombing events are not considered, then life on Earth will evolve from 4.55 billion to 3.5 billion years during this 1 billion years; if you consider the late heavy bombing events, then From 3.9 billion to 3.5 billion years, life evolved in just 400 million years.
Surface water activity on Mars lasts for about 3.5 billion years, and groundwater activity lasts for about 2.5 billion years.[4] . In other words, a suitable time on Mars is completely enough for life to evolve from nothing.
Fossils of multicellular organisms 600 million years ago Picture/wikipedia
Ediacaran Biological Recovery Picture/wikipedia
About 530 million years ago, the well-known Cambrian life exploded. During this period, the ancestors of most living creatures appeared, including the distant ancestors of human beings-fish animals.
One of the earliest fish-shaped animals-Kunming fish Picture/wikipedia