This is what Prof. Omri Vandel, from the Rakah Institute of Physics at the Hebrew University, said in an interview with the website the scientist following the discovery, which was predicted in an article he recently wrote together with Prof. Yosef Gil from the Institute of Life Sciences at the Hebrew University, which was accepted for publication in the International Journal of Astrobiology, but has not yet been published and actually provides evidence Observational to the predictions given in it

"Detecting water vapor in the atmosphere of a planet similar to Earth is a big step on the way to discovering life in space." This is what Prof. Omri Vandel, from the Rakah Institute of Physics at the Hebrew University, said in an interview with the website of the scientist following the discovery, which was predicted in an article he recently wrote together with Prof. Yosef Gil from the Institute of Life Sciences at the Hebrew University, which was accepted for publication in the International Journal of Astrobiology, but has not yet been published and actually provides evidence Observational to the predictions given in it.
As you remember yesterday, scientists from Canada revealed that they managed to detect water vapor and maybe even liquid water clouds in the atmosphere of the planet K2-18b. This planet is nine times more massive than our Earth and is in the habitable zone of the star it orbits. It is an M-type star smaller and cooler than our Sun (a red dwarf), but due to K2-18b's proximity to its star, the planet receives almost the same amount of total energy from its star as our Earth receives from the Sun. The planet is 110 light years away, it is twice the size of Earth and its year lasts 33 Earth days.
In the theoretical article, the Israeli researchers write: "Kepler space telescope data show a high prevalence of relatively small planets (similar in size to twice that of Earth), orbiting red dwarf-type suns in the habitable zone (where the temperature of the planet's surface allows liquid water to exist). Therefore, these stars may be promising targets for searching for evidence of the existence of biology and life."
"Planets whose orbits are in the habitable zone of red dwarfs are apparently gravitationally locked (always facing the same side to their Sun, similar to the Moon and the Earth). Several recently published works cast doubt on the ability of this type of planet to support life. On the other hand, it is possible to show Because temperatures suitable for the existence of liquid water and even organic molecules may exist in locked planets of red dwarfs for a wide range of atmospheres (A. Wandel (2018, Astrophysical Journal 858, 165.
"The paper describes the climate (surface temperature distribution) of locked planets as a function of radiation intensity and atmospheric properties: the greenhouse effect and heat convection. The previous model (described in the 2018 paper and describing fully locked planets) is extended to synchronous (partially locked) planets." It has been found that red dwarfs, and also K-type stars (more similar to our Sun), may support life for a wider range of distance from the sun and atmospheric conditions, than was commonly thought in the past.
"In particular, we claim that on such planets it is likely that conditions suitable for life, and in particular for photosynthesis and oxygen, which on Earth were the key to the development of complex life, will exist. Different climate scenarios and the biological significance of gravitational locking for complex life are reviewed. We show that when the effect of continuous radiation is taken into account, the amount of radiation available for photosynthesis (PAR) in locked or synchronous planets, in particular those Surrounding red dwarf suns, may produce high growth productivity, analogous to midsummer growth in northern latitudes on Earth."

"Pending the findings of the space telescopes TESS (already operating today) and JWST (the James Webb Space Telescope expected to be launched in 2021) the article discusses the implications of the above results for the discovery of biological markers such as liquid water and oxygen, and also for the prevalence of planets with biology and life."
As mentioned, since the article is still in the proofreading stages, Vandel and Gil added a note (note added in proof) regarding the confirmation of their prediction in which water vapor was discovered on the planet K2-18b.
In an interview with the scientist website, Prof. Wendel says: "We predicted that the James Webb space telescope, which will replace the Hubble, would be powerful enough to detect the chemical composition of small planets relatively far from their sun. In the end, the Hubble space telescope was also able to perform the spectral separation required to understand the composition of the atmosphere."
As we know, most of the planets were discovered by the method of transits, that is, a very slight change in the light intensity of a star, when the planet passes in front of it, as it appears from our point of view. If you observe such a transition at different wavelengths, you can conclude from this about the composition of the atmosphere. We did not believe that Hubble would have the capacity to absorb enough light to perform the spectral separation.
What technique did the researchers use to discover the water vapor in K2-18b?
"As we know, we are not able to directly see planets outside the solar system, except in a few cases. In those cases, it is hot planets - planets as large as Jupiter but very close to their sun, and therefore very hot, and then their atmosphere is hot and emits lines that can be detected in their spectrum, but for stars Smaller than the size of the Earth, rocky planets on which there is a chance for life both their size and relatively low temperatures did not allow such a discovery are limited to the detection of planets that pass in front of their sun in a cyclical manner. Every time a planet stabilizes in front of its sun, we experience a small dimming of the star's light - this is the method used by the Kepler space telescope, which discovered thousands of planets in its four years of operation. But this method is not sufficient for analyzing the composition The atmosphere. To analyze the atmosphere, we use the fact that the atmosphere reacts differently to different wavelengths, for example water vapor They absorb the light at a certain wavelength and not others. If we look at the transition of the planet in this area, we can see that the dimming is slightly stronger because we are observing not only the ground of the planet but also its atmosphere, which is opaque to these frequencies.
In the discovery article in Nature from this week, the researchers show a series of transit photographs at different wavelengths, and in those that correspond to water vapor, the descent is a little deeper, the star appears a little bigger because the atmosphere also participates in hiding the sun at these wavelengths. At other wavelengths that are not absorbed by the atmosphere, only the ground surface of the planet obscures the sun, so the drop is a little smaller. "
And how does your article relate to the topic?
Prof. Wendel: For years Prof. Gil and I have been publishing a series of articles in which we try to create a picture of planets around red dwarfs and seek to see to what extent they can be suitable for life. The adaptation to life is based on two main parameters. The first - is there a chance of having liquid water in them - that is, if their temperature will allow liquid water and the second parameter is whether their atmosphere can survive the intense activity of the red dwarf in the first billion years of its development.
We built a model that schematically takes into account the atmosphere where the heat measurements on the surface of a planet do not depend only on the distance from its sun and the composition of the sun but also on the composition of the atmosphere. In the new paper we show that, at least theoretically, gravitationally locked planets orbiting red dwarfs have a range of atmospheres and many of them support liquid water.
What about detecting oxygen which is a stronger marker for life?
Such a discovery is the next important discovery. The next step would be to try to detect oxygen or ozone in the atmosphere of this planet or perhaps others. The researchers created a series of possible models for the composition of the atmosphere and three of the models matched the observations and the models contained hydrogen and helium, water vapor and one model also contained nitrogen, and the models were built with some having clouds and others not. Oxygen arrived in the Earth's atmosphere due to the photosynthesis activity of microscopic marine organisms for billions of years, a fact that it is not found in the atmosphere of any other planet in the solar system, but oxygen can also be formed from the decomposition of water, so to be sure that there is life there you also need to discover methane and di carbon monoxide."
In conclusion, Prof. Wendel says: "This is the first time that we have succeeded in discovering an atmosphere and a spectral signature of a planet similar in size to Earth and in the habitable zone. What played in the planet's favor is the fact that it is 8 times more massive and its gravity is 2 times greater than Earth's, so it can hold more atmosphere Massive. As mentioned, our article has not yet been published in print. but only online And we have already received direct approval, I observed."
More of the topic in Hayadan: (Beresheet is the Hebrew name for the book of Genesis)
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With all due respect for the discovery and information. It's really irrelevant
These are huge distances of thousands of light years and we do not have the ability to get there in any way even if there is a spaceship at twice the speed of light
Nothing to do with this information?? Imagine that Newton, Einstein or even Edison would have thought like this at the beginning of their career. It is clear that currently it is not possible to travel such distances, but only a few hundred years ago it was also impossible to leave our planet at all.
Nothing to do with this information.
It is impossible to communicate with them and certainly not to send anything there. is nothing.
Understanding the universe is wonderful and it is the basis for understanding life as well.
So that they don't think, "Well, we can fly there to visit and come back." After all, it is clear that only the light comes from there approximately after more than a hundred years.
The schoolchildren of the future will burst out laughing when told that our generation was skeptical about extraterrestrial life. They will laugh when they hear that they needed scientists and space vehicles to understand that there is other life. In the future it will be a settled fact that people will live in every possible hole in the universe, including inside burning and hot mega suns... and also on top of atoms and particles. Life is everywhere. Go ahead, not everything requires proof with a minimum of 3 pieces of data...