Since the beginning of this century, people have discovered a large number of super-Earths in the process of exploring the universe, and some of them seem very special, such as the Gliese 581g that we are going to talk about today.
After its discovery, scientist Stephen Waters has publicly stated that the chances of life existing here should be 100 percent.
So, how was Super Earth Gliese 581g discovered by humans? And what is so special about it?
What's so special about Super Earth Gliese 581g?
As we all know, the Earth's resources are limited, plus the sun will be old in another 5 billion years or so, in this case, humans want to continue civilization, we must find a new home. Because of this, in recent years, the search for habitable planets is as important as the search for extraterrestrial signals.
During the search, a number of planets with super similarities to Earth were discovered, and since they are often larger than Earth, they are collectively referred to as "super-Earths".
According to the data, Gliese 581g was discovered in September 2010, when a team of researchers from Santa Cruz, California, announced the discovery, indicating that there is a habitable planet very close to Earth.
In fact, some of its "siblings" were discovered before the existence of Gliese 581g was confirmed. For example, in 2007, Gliese 581c was discovered, and later Gliese 581d was discovered, both of which were determined to be just within the habitable zone.
In the galaxy where these "Earth-like planets" are located, there is also a glowing star, but this star is not the same as the Sun, but a red dwarf. The red dwarf is the most common type of star in the universe. It is smaller and its surface luminosity is not as bright, but it is exceptionally long-lived.
This red dwarf with many habitable planets is known as Gliese 581, which is located in the constellation Libra and has a mass about 1/3 of the Sun's. From data studies, Gliese 581 is only about 0.2% as bright as the Sun and has an effective temperature of 3200 K, much lower than the Sun's 5778 K.
Because of this, one needs to place it closer when defining the habitable zone, after all, if it is too far away, it will be difficult to receive the energy emitted by the red dwarf.
The distance between the habitable zone and the stars in this galaxy has been estimated to be about 10% of the distance between the habitable zone and the stars in the solar system. In that case, its habitable planets would have to stick closer than Mercury in our solar system!
According to the data from the U.S. high-resolution fly-eye probe study, Gliese 581 should have six planets, among which Gliese 581g should be the most habitable.
To briefly introduce the basics of Gliese 581g, it is about 20.5 light years away from Earth and since its discovery has been identified as the exoplanet most similar to Earth. Its mass should be three or four times that of the Earth, and its orbit is 0.146 astronomical units away from Gliese 581, which is about 9.65 million kilometers. The rotation period is equal to the rotation period, both being 37 Earth days.
Due to its very close proximity, Gliese 581g is tidally locked by Gliese 581, just like the Moon is tidally locked by the Earth. In this case, it has been facing its parent star only on one side.
Speaking of which, you may be thinking, can this still be considered a habitable planet? Wouldn't it be hot as hell and cold as hell on one side?
This is related to the special thing of Gliese 581g, from the current observation and inference, this guy's atmosphere is far thicker than Earth's, so this means it has a stronger greenhouse effect. With such an addition, the side with the back to the red dwarf should not be as cold as one would expect.
In addition to this, it is thought that the thick atmosphere of Gliese 581g allows evaporative compounds to move. When these compounds move from the front side of the scorched to the back side, there is a warming effect.
Even if its real situation is different from people's inference, its morning and evening circle zone can be a livable place, plus it is relatively large, so there should still be a more adequate area for human migrants to live.
And, it is true that people are more than satisfied with the distance of only 20.5 light-years between it and us. After all, it is not like the previously discovered super-Earths, which are easily hundreds of light-years, tens of thousands of light-years, or even hundreds of thousands of light-years away from us. This kind of super Earth even if it is habitable again, humans are also very difficult to reach, to know that we are not only short-lived, the flight speed of the vehicle is also very crotch.
It is worth mentioning that, in addition to the Gliese 581g "three conditions" and other relatively satisfied, people are also full of expectations for the alien life on this. There were even scientists who asserted that the chances of life here are 100%, what is going on?
The chance of life existence is 100%?
In fact, this claim originated from the discoverer of Gliese 581g, Steven Vogt, perhaps particularly excited about his discovery of a new habitable planet, who had made it clear in an interview that although he was not a formal biologist, he could conclude that the chances of life existing on Gliese 581g were 100 percent.
Obviously, although we do not know how he has such confidence, but this to "exaggerate the bragging" about their discovery of exoplanets does not seem to be a problem.
In addition, Gliese 581g is indeed in the habitable zone, and is a rocky planet and a thick atmosphere, in this case, the chances of the existence of liquid water is quite high.
You know, generally this kind of life in the mouth of the scholars are different from the understanding of unusual organisms, whether it is a single-celled organisms or mold, can be counted as life.
However, in fact, before humans set foot on this planet, any 100% assertion is not scientific enough. It is important to know that similar conditions have been experienced before, and it is not the case that having a thick atmosphere is capable of harboring life.
The most typical one should be the once much-anticipated but ultimately fallen "star of hell" Venus.
In the 1950s, Venus was thought to have vast oceans and lush rainforests beneath its thick atmosphere, and was long thought to be an alternative planet for human immigration.
But then, the visit of the probe shattered our dreams, and instead of a vibrant atmosphere, there was a depressing silence. The horrible greenhouse effect of the thick atmosphere turned the surface of Venus into a "pressure cooker".
It is hard to say if a similar situation will occur with the Gliese 581g, which is actually very possible from an objective point of view. Because of this, it remains unknown whether life exists here or not.
So, if humans are to migrate to space in the future, will Gliese 581g be put into the top of the list?
Is it the preferred planet for immigration?
In fact, humans should continue to screen and then select more recent ones. Because for us, spanning a distance of 1 light year is considered a dream now, and in this case 2.05 billion light years is still a bit too long.
And there has been a lot of controversy over Gliese 581g, both about its environment and about whether the planet is real. If in the future, people can't figure out all kinds of problems, they will definitely not set off to this place.
After all, this kind of migration is often "desperate", and if it is really in a state similar to that of Venus and not at all habitable, humans will have made a trip for nothing.
So, do you think Gliese 581g has the strength to compete for the preferred immigrant planet?