Habitable Earth-like planets - is it a fantasy? The researchers suggest that those in the universe are not uncommon. Approximately around one of the five sun-like stars, in particular those observed from the Kepler astronomical satellite (NASA), there is a habitable zone - a supposed space territory, the planets of which, under certain circumstances, could become habitable. The temperature on their surface contributes to the existence of water in the liquid phase (that is, it does not boil and does not turn into ice).
Among the sparkling scattering of stars
The nearest habitable planets are perhaps the most alluring. The star, to which we are "almost within reach" (after Alpha Centauri) is located at a distance of 12 light years from Earth. It illuminates the exoplanet Tau Ceti. For reference: 1 light year is 12 earth calendar months. In terms of distances - 9,460,000 million kilometers. By universal standards - nothing special.
For earthlings, this is a fantastic distance. They do not yet have the opportunity to personally get acquainted with representatives of the “far abroad”. Although human beings have looked at the stars for thousands of years. And they probably thought: “Among thisa sparkling scattering of places reminiscent of my land?”
In 1995, a planet suitable for life was first discovered. Most readers will hardly recognize its name: PSR B1257+12 B, the star of Gamma Cephei. After the opening, the unusual price list began to grow rapidly. Previously, when tracking planets, experts focused on radial velocity (the projection of the speed of stars onto the line of sight).
Climate is changing
Later, with the help of instruments such as the Kepler telescope, they switched to studying the variation in the brightness of planets moving in orbits around their stars ("transit"). Repeated observations have convinced researchers that these are indeed celestial bodies, and not huge and cold dark spots.
New planets suitable for life began to be found when the astronauts applied the method of statistical analysis. There was a huge amount of data to work with. At one of the conferences at NASA, it was said that hundreds of potentially habitable objects were discovered with the help of the Kepler satellite. And this is not the limit!
Let's try to figure out whether the exoplanets discovered by modern researchers really have life, or they only partially meet some criteria for habitability. We need a serious assessment. It is not easy to make it: the distances are huge and beyond the capabilities of modern science and technology.
No life without water
Why does a person look for planets suitable for life? Out of curiosity? No. The climate on our unique, life-filled globe is changing. Mankind is being hauntedheat, frost, floods, dust storms. All this can end badly. Our confidence in the viability of only one Earth is not only joyful, but also worrying.
Political, financial, humanitarian, scientific reasons make us a biological species, extremely interested in the habitability of as many planets as possible. New planets suitable for human life will make it possible to understand the trend of changes in terrestrial weather conditions, to determine the possibilities of survival in the coming climatic conditions. Decide what needs to be done to stop the deterioration of weather conditions, find out what is the reason for such a strong dependence on carbon.
Thus, habitable planets will give people the opportunity to find cleaner energy sources, stop degrading the climate for financial gain and comfort. Perhaps this will require new hardware platforms that will allow us to go on such long journeys.
Venus Heat
Many people wonder how they will feel when they encounter alien creatures when they arrive on habitable planets. And so they are very interested in habitable zones (they are also called "Goldilocks"), where there are celestial bodies with a moderate average surface temperature. This allows water to be between the gaseous and solid state of aggregation (only then can you "cook the porridge of life").
Planets suitable forscientists have been looking for life for a long time and persistently. Yes, mankind hopes to find extraterrestrial reserves of liquid in order to use them for practical purposes. However, H2O is perhaps the main indicator of the existence of alien life in different galaxies and throughout the universe. Although it is problematic for life to exist outside the Earth.
There are celestial bodies where it's hot as hell. Under such conditions, some volumes of hydrogen and oxygen are produced. The oxygen combines with the carbon to form carbon dioxide, and then the hydrogen simply escapes into space. This happened to Venus.
The Kingdom of the Snow Queen
There are planets where the Snow Queen probably rests. It is always cold there, the reservoirs are vast skating rinks. Under the ice cover, deep lakes with flowing water may lurk, but they are still uninhabitable areas. Such a picture is observed on the kings of cold Mars, Jupiter, Saturn.
Should they be included in planets suitable for human life? No, it's a habitable zone in a rough sense: a place where waves could theoretically "lap". Unfortunately, not everything is solved by answering a simple equation with the distance to the star "in the numerator" and the amount of energy output "in the denominator". Of great importance is the presence of the planet's atmosphere.
In fact, Venus and Mars "dwell" in our own solar system. But the dense Venusian atmosphere is saturated with carbon dioxide, which traps energy from the Sun and creates the adverse effect of a red-hot furnace that can destroy all life. BUTMars?
Mars Rink
In contrast to the hot symbol of love, on the bellicose symbol of masculinity, the atmosphere is so thin that it does not trap heat, so it is a frighteningly cold “bun”. If the opposites had an earthly atmosphere (plus the presence of mountains with minerals) - they could be worlds quite suitable for the development and preservation of life.
If the antipodes "shared the excess", it would be possible to mitigate the heat and melt the ice … And planets suitable for life would turn out. However, these are just fantasies. Talking about the possibility of the presence of other worlds in the Milky Way, we must understand: their presence in the habitable zone does not change things if the shape and composition of the atmosphere of the planets are unfavorable.
They all revolve around stars called "red dwarfs". Even if one imagines that celestial bodies are suitable for human life, it is not very inspiring to spend one's life surrounded by landscapes in bloody tones. But the main thing: young dwarfs are extremely active. They experience huge solar flares and coronal mass ejections.
Active midgets
This will inevitably have a detrimental effect on the life of any planets that happen to be nearby, even if they have liquid water. The magnetic fields of such "raging suns" are so powerful that they can crush all the "neighbors". But after a few hundred million years of high activity, red dwarfs settle down and further stretch their hydrogen fuel reserves to about trillions of years.
If life survives in the early stages of development, then it will have every chance for a long existence next to the calmed down "Lilliputians". And new planets suitable for human life (photo below) will decorate the Universe. Thus, in search of a new home among the stars or life in the Universe, we are aware that the habitable zone is only a rough guide.
The field of coverage of the Kepler spacecraft is 150,000 stars. Most are too bright to see. But Petigura of the California Institute of Technology and his colleagues were able to study 42,000 "silent" stars and concluded that 603 planets can be included in the number of habitable candidates.
Seek and find
Habitable planets vary in size. Ten of them are within a radius of up to two times that of Earth. To compare the desired radii, the scientists used the Keck telescope installed in Hawaii. Complicated calculations were made, corrective amendments were made.
As a result, it turned out that about 22 percent of sun-like stars have planetary satellites resembling the size of the Earth, they are potentially habitable. Let's list some of the exoplanets.
The Tau Kita E mentioned at the beginning was discovered in 2012. Located in the constellation Cetus. It is considered an unconfirmed candidate for habitable space objects. The period of revolution of the planet around the star (sidereal period) is 168 Earth days. The orbit is near the habitable zone. Surface temperature averages 70 degrees Celsius(Earth has 15).
This "pretender" is located at a distance of 473 light years from Earth and is named Kepler 438b in the constellation Lyra. Refers to the star Kepler 438, which is 4.4 billion years older than the Sun. The silent red dwarf does not shine very brightly, so it is not easy to see the situation carefully.
Gliese and others
The unconfirmed "madame" Gliese 667С E is also included in the habitable planets. It revolves around a star from the constellation Scorpio - this is a whole system: a red and two orange dwarfs. The age of the “honest company” is from 2 to 10 billion years. It is located 22 light years from Earth. Year - 62 days (Earth days).
Kepler186f "cuts ellipses" around a red dwarf in the constellation Cygnus, which is 561 light years away. His star is not as big and hot as the Sun. A year is 131 Earth days.
Captain B "spins" around a star from the constellation Pictor. It is larger than the Sun - with a mass of 0.28 times, with a radius of 0.29. The dwarf is about 8 billion years old, 13 light years before it. Kapteyn is an unproven exoplanet whose day lasts 48 Earth days. Radius not calculated, five times heavier than Earth.
Distant worlds await us
Wolf 1061С refers to the luminary from the constellation Ophiuchus. Rotates with its star synchronously. Therefore, one side is always hot, the other cold. It is 14 light years away. Maybe it's a rocky planet. The surface temperature is suitable for the existence of liquid water. The gravitational force (gravity) is greater than the earth's almosttwice.
This is not the whole list of promising riddles! So “there are a lot of us in the Universe, and we are in vests!” It’s just that it’s difficult to prove it, and even more so to get it personally. But we know that there are planets suitable for human life!
