Lead
Human beings have always had a strong interest in extraterrestrial life, and there is such a wide range of life forms on Earth, is there only life form on Earth in the universe?
Humans have detected a terrestrial planet, Gliese 581g, 2.04 billion light-years away from Earth, and Gliese 581g may be the best hope for life in the universe.
A year of Gliese 581g is equal to one day of the Earth, and scientists believe that Gliese 581g may be 100% life-bearing!
1. Aliens.
Gliese 581g was discovered by Michel Mayor, an astronomer at the Geneva Observatory in Switzerland, in 2009, although after many screenings, some astronomers even thought that the planet did not exist, but with the development of various sophisticated equipment, finally in 2010, the planet in the Gliese 581 galaxy in Scorpio was finally confirmed by scientists.
The planet is 20.4 light-years away from Earth, and the distance of 20.4 light-years is out of reach for humans, even if it is to travel at the speed of light, it will take 20.4 years, so humans will never reach this planet.
However, the planet Gliese 581g is the most Earth-like planet that human beings have detected so far, and from the information that human beings have on the earth, Gliese 581g has a strong possibility of life.
In the eyes of scientists, Gliese 581g is very similar to Earth, but it also has many differences.
For example, Gliese 581g is much larger than Earth, 1.3 times in diameter and 3.6 times more massive, which means that the planet is very large, and such a mass also means that the planet's gravity is very large.
On planets with strong gravity, human activities on it will also be greatly affected, so human activities on it are also very inconvenient.
However, the diameter and mass of Gliese 581g are only similar, but there is an even greater difference between Gliese 581g and Earth, that is, the rotation period and revolution period of this planet are very peculiar.
The rotation period of this planet is very close to the orbital period, so that the year of this planet is about the same as the day of the earth, so scientists believe that this planet is not suitable for human habitation, but this planet has the conditions for the existence of life, or this planet is the best direction for human exploration of extraterrestrial life.
Not far from the planet, there is also a red star, which scientists call a red dwarf, which is a relatively small star, only about half the mass of the sun, and much smaller in diameter than the sun.
The luminosity is only 1.5% of the sun, so this red dwarf star is very dim, and the luminosity of the stars seen by humans on the earth is brighter than this red dwarf, so humans cannot see this red dwarf.
However, such an inconspicuous red dwarf star has a strong photosynthesis, because the red dwarf star is small in size and the core temperature is much lower, so in the case of nuclear reactions, it can last for a very long time, can last for billions of years.
Compared to the Sun, the Sun can only last for 10 billion years, so red dwarfs are more durable, providing a constant source of light and heat to the surrounding planets.
There are also many planets around the red dwarf, and scientists believe that there may be 7 planets around the red dwarf, 3 of which are terrestrial planets, and this Gliese 581g is one of them.
The terrestrial planets around the red dwarf are tidally locked, so this Gliese 581g is no exception, a year on Earth is equal to 365 days, but on Gliese 581g a year is equal to 32 days.
The terrestrial planets around the red dwarf, due to the very short orbital period, will be affected by the tidal force of the red dwarf in the process of orbit, which will eventually lead to the result of tidal locking.
2. The possibility of the existence of life.
Although Gliese 581g is very similar to the Earth in many ways, it cannot be generalized, there is a large amount of water on the Earth, and at a temperature that is extremely suitable for life, a variety of microorganisms have been formed, and finally human beings have evolved over countless years.
The difference between Gliese 581g and the Earth is that the surface temperature of this planet is relatively low, from -31 degrees to -12 degrees, which is quite cold for humans, but for the existence of life, this temperature is very suitable, because at this temperature, water can exist in liquid form.
Tens of millions of tonnes of water vapour rise during the revolution of Gliese 581g, eventually condensing into clouds at extremely cold temperatures, and then falling to the ground in the form of rain, eventually forming rivers and oceans.
This means that there is a lot of water on Gliese 581g, and there are also abundant nutrients, which are the conditions for life to survive.
In addition, due to the large amount of water on Gliese 581g, it is also very likely that there is an ocean, and the existence of the ocean also means that this planet is very rich in life.
Moreover, the existence of the ocean can also provide enough oxygen for life on this planet, so it is very likely that the life forms on Gliese 581g are similar to those of fish on Earth.
In 2010, a special signal was detected on the surface of the planet, which was thought to be emitted by an extraterrestrial civilization, and although scientists were skeptical of this claim, people's curiosity led them to think that it was a signal of an extraterrestrial civilization.
The source of this signal has not yet been confirmed by scientists, so scientists continue to observe this planet, hoping to find life on this planet.
However, scientists are not very confident in the existence of life on this planet, on the one hand, because this planet is too far away from the earth, so there is no way for humans to go to this planet to investigate, so it is difficult for scientists to know whether there is life on this planet.
On the other hand, the life on Gliese 581g also needs to be different from the life forms on Earth, so human beings need to redefine life in the universe in order to be able to study the life on Gliese 581g.
III. Conclusion
In the universe, there may be hundreds of millions of planets like Gliese 581g, and there are also places that humans can't reach, and humans have too many destinations to choose from.
If there really is life in a place that humans can't reach, then human beings can only silently bless the life there to live there peacefully.
On the road of human exploration of extraterrestrial life, if one day human beings really come into contact with aliens, it will be a very important thing, and it may also promote the development trajectory of human civilization.
There may be more terrestrial planets around red dwarfs, and these terrestrial planets are tidally locked, so the surrounding terrestrial planets will also have a strong attraction to each other, so that they are also likely to communicate and interact with each other to form a series of civilizations.
If human beings want to reach these planets, they need to gently exploit the starry sky and not destroy the planet's environment, so as to achieve the goal of peaceful coexistence.
When humans carry out interstellar migration, more factors need to be taken into account, not only suitable for human habitation, but also human adaptability on it, as well as survival skills and so on.