The earth is a habitable planet and the homeland where mankind has survived for millions of years. After human beings walked out of the earth, we began to search for extraterrestrial life. Scientists search for extraterrestrial life mainly based on the ecology of the earth.
The fact that the earth can give birth to life indicates that the earth has all the materials and natural conditions needed for life to survive. If other planets also have an ecological environment similar to the earth, the possibility of life will be very high. Unfortunately, there is only one beautiful ecological planet in the solar system, the Earth, and there is no second habitable planet that is very similar to the Earth.
If so, does it mean that the solar system only has life on the earth, and there can be no life on other planets? In the early days, scientists also thought so, but with the continuous advancement of human technology and the continuous improvement of life cognition, the conditions required for extraterrestrial life are also constantly relaxed.
Nowadays, scientists searching for alien life are no longer limited to an ecological environment like the earth, because an ecological planet that is exactly the same as the earth in the universe may be very rare or even non-existent. From the perspective of the cosmic scale, life may exist universally in the universe. If this is the case, it means that life’s requirements for the ecological environment are also diverse.
Regardless of the basic requirements of life for the ecological environment, different planets may give birth to different forms of life, but for a planet to give birth to life, some of the most basic conditions still have to be met. Among them, there is one of the most important basic conditions. It is generally recognized by scientists that there must be an atmosphere.
The earth’s ability to form an excellent ecosystem and be able to give birth to life has an important relationship with the earth’s thick atmosphere. The atmosphere is very important for the protection of the surface of a planet. We all know that the universe is not very flat, and there are many disasters that can threaten the surface of the planet, such as the impact of some asteroids.
If a planet does not have an atmosphere, such as the moon, then the asteroid will directly hit the surface of the planet, causing devastating disasters. With the atmosphere, resistance can be generated, and the asteroids are continuously consumed before they hit the ground through friction and heat, thereby protecting the ecosystem on the planet’s surface.
What’s more important is that the universe has too much and too powerful radiation, which is the end of life. Life can adapt to a variety of complex and harsh planetary surface environments, but it does not have much resistance to the strong radiation in the universe. In addition to the magnetic field, what can absorb and block the cosmic radiation is the atmosphere.
This shows how important the atmosphere is to the birth of life. When scientists are looking for extraterrestrial life, their main targets are also on planets with obvious atmospheres. One reason why Mars has attracted more attention from humans is that it is close to the earth, and the other reason is that it has a thin atmosphere. With the existence of this atmosphere, life may exist.
In addition to Mars, have scientists discovered planets in the solar system that are more likely to give birth to life than Mars? The answer is yes. Scientists have found a planet very similar to the early Earth, with an atmosphere and liquid matter on it, and the possibility of life is higher than that of Mars.
This planet is not a planet, but Saturn’s largest moon Titan. Titan, also known as the Left Titan, is the largest satellite of Saturn and the second largest satellite of the solar system. As a satellite, its mass and volume can’t be compared with planets, and a satellite is relatively small and basically There will be no atmosphere.
However, through observations, scientists discovered that Titan is a different satellite. It has a thick atmosphere. 98.44% of the atmosphere is nitrogen. It is the only nitrogen-rich star in the solar system other than the earth. The structure of this atmosphere is similar to that of the planet. The early Earth is very similar, and scientists call it a replica of the early Earth.
In order to explore Titan, NASA launched Cassini in 1997. In addition to exploring Saturn, a more important mission is to explore Titan. Through Cassini’s 20 years of diligent work, we have returned a lot of data about Saturn and Titan.
Through these data, we have a preliminary understanding of Titan. Titan is very similar to the early Earth. It not only has thunderstorms, mountains, basins, etc., but also liquid substances on the surface. So will these liquid substances be water? Of course not. In fact, there is no oxygen in Titan’s atmospheric structure. In addition to the main nitrogen, it is more methane and ethane.
The thunderstorm on Titan does not drop water, but liquid methane and ethane, which fall on the surface in the form of rainfall, forming a sea of methane. Methane is also an organic matter, and on the earth, the source of methane is mainly microorganisms.
Titan has a deep atmosphere and its own special ecosystem, so it is very possible that special life on this planet will be born on methane. Life does not necessarily need oxygen to breathe and survive. It can be carbon dioxide or methane and other substances. Therefore, Titan is highly suspected of the existence of life. In the future, scientists want to discover extraterrestrial life. There are two main goals: one It’s Mars and the other is Titan.
Of course, the difficulty of exploring Titan is higher than that of Mars. This is because Titan’s atmosphere is thicker and the surface temperature is also as low as minus 179 degrees Celsius. These environments undoubtedly added a lot of difficulties to the probe’s landing, and the Cassini launched by humans was also in orbit to observe Titan, and it did not really land on the surface of the soil.
Because Titan has a thick atmosphere and blocked by clouds, we do not know the real and more detailed conditions on its surface. If you want to understand the situation on the surface of Titan and know whether there is life, then you need the probe to actually get on the surface of Titan, and it may take some time to achieve this goal.
Scientists have planned to explore Titan again. The next exploration may try to land the probe on the surface of Titan. If there are special life on it, it will be discovered. Moreover, scientists have far higher expectations for the existence of life on Titan than on Mars. It is possible that in the near future, the first discovery of extraterrestrial life by humans will be realized on Titan.