Last week, the world literally applauded: near the TRAPPIST-1 star, seven Earth-sized planets with a bunch of additional pleasant features were found. It would seem that there are seven solid planets, while there is not a word about life, aliens or other surprises, but there was noise all over the world. What's the salt? Here's how: The discovery was an "important step" in the search for extraterrestrial life in the universe, says Amory Triod, an astronomer at the University of Cambridge. And even if this exciting new discovery turns out to be yet another sad impasse in research, it will have far-reaching implications for future science.
Atmospheres without thick hydrogen layers
Scientists have already confirmed that at least two planets in the TRAPPIST-1 star system (the size of which, if you compare with our star, would be the size of a golf ball, and the Sun - for a basketball) are not completely covered with a thick layer of hydrogen - therefore they must have a solid soil, like the Earth.
While this may not be tolerated by the brain, it helps to rule out the possibility that these planets are just giant balls of gas, therefore, unable to support life. Gas planets are often found in the orbits of stars of this size, and these seven planets are rather the exception to the general rule. And this means that scientists admit that there may be many more potentially habitable planets in the Universe than it was assumed.
Ozone and methane present
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For a planet to be life-friendly, it needs a special mix of chemicals and variables. Not too hot, not too cold. Not too gaseous, not too solid. There should be a relatively solid landscape, plenty of light, an atmosphere of ideal thickness, favorable for temperate climates and water that can collect in lakes, seas or oceans.
The presence of ozone (which may be a byproduct of oxygen produced by photosynthetic plants) in the atmosphere provides an invaluable protective layer against the harmful effects of ultraviolet (UV) radiation from the sun.
Scientists are confident they will find a combination of ozone and methane in the atmosphere of at least three newly discovered planets, making them favorable for life.
Moreover, the presence of methane and oxygen together in the air of one or more planets could indicate an invisible source of life replenishing these gases. “If you have a combination of ozone and methane in the presence of carbon dioxide and water, there is only one obvious explanation,” says astronomer Michael Gillon of the University of Liege in Belgium. "That's life".
M-dwarfs live longer, which means life will have more time
The TRAPPIST-1 star was classified as an "M-dwarf". Such stars are extremely common in the Universe and tend to be relatively small and faint. TRAPPIST-1 is also classified as an "ultracold" M-dwarf star, so it is the coldest star there can be.
M-dwarfs are notorious for burning their nuclear fuel relatively slowly compared to hotter, brighter stars like our Sun - so they can shed light on neighboring planets for long periods of time, even trillions of years.
(For comparison: the sun has been burning for 4.6 billion years and will finally burn out in the next 5 billion years).
The long lifespan means that complex biological life has more time to "evolve out of swamp mud," says Dr. Seth Shostak, an astronomer at the SETI Institute. "If you are looking for complex biology, the older the better."
New thoughts on planetary formation
This discovery has already become a major victory for science, because even if these planets turn out to be unfavorable for life, this discovery will no doubt provide scientists with an ideal scenario for testing a wide range of hypotheses.
The TRAPPIST-1 system can be compared "not only with the Earth and other planets in our solar system," says Michael Gillon, but "with itself."
Since these planets are believed to have formed in a single protoplanetary disk (a rotating disk of dense gas and dust surrounding a newly formed star), scientists are confident that small but significant differences in the chemical composition and atmosphere of each planet will provide significant clues about the history and evolution of the planets. …
This information can then be used to better analyze the evolution of other planets, thereby increasing our own store of knowledge about the Universe.
Clear vision of distant worlds
The newly discovered system is likely to be a valuable model for extracting data that will allow us to better understand planets and galaxies further away, especially in the context of the search for life.
With TRAPPIST-1, scientists will test their "fears and desires for other planets orbiting very cold, very light M-dwarf stars," says Sara Seeger, a planetary theorist at MIT.
At best, scientists will find irrefutable signs of life. In the worst case, it's also good: scientists may not be able to determine if oxygen is produced on one of the planets of the TRAPPIST-1 system by life forms or not. That's pretty good news too. Seeger assures us that the only downside is that it will take us longer to find the source.
Earth-sized planets may be much larger than thought
Although scientists have long assumed that there are many Earth-sized planets in the Universe, until they discovered the TRAPPIST-1 system, these unique planets were considered small and distant. Now that this system has been discovered, and so close to our own, the simplest laws of probability indicate that there are many more such systems in the universe than previously thought.
In addition, there will be more M-dwarf stars in the universe with similar properties than previously thought. This means that we will have a better chance of finding extraterrestrial life, and scientists who are looking for radio signals sent by alien life forms may have been looking in the wrong place all this time.
Spitzer Space Telescope Proved Its Excellence
While most of the credit for this discovery will go to the men and women who have worked on this project for months, some respect should be paid to the incredibly powerful and cool Spitzer space telescope, which made this discovery.
Launched in 2003, this infrared space telescope has captured and transmitted the amazing mysteries of space over the past 14 years, traveling in a heliocentric orbit.
Armed with an array of infrared cameras, an infrared spectrograph and a multiband photometer, the telescope can capture impressive images with variegated detail. Among his discoveries is the first light emitted by exoplanets that we have been able to find and witness.
Each planet in the TRAPPIST-1 system was detected due to small dips in the TRAPPIST-1 light. These blackouts occurred whenever one of the planets passed in front of a star, and a giant telescope lens transmitted this light to NASA, where it was analyzed with an estimate of the size and mass of each star.
This system - 40 light years from Earth - is relatively close to us
The universe, in all its vast glory, no doubt contains many planets that are very similar to the planets in the TRAPPIST-1 system. However, we rarely find planets so close to us.
40 light years is certainly not nonsense, but it is not beyond. Using modern technology, it would take 44 million years to travel 400 trillion kilometers from Earth. But on a cosmic scale, 40 light years is very small, so scientists will be able to draw conclusions about our solar system and planetary systems that are difficult to "see" if they take data on the TRAPPIST-1 system as a basis.
Ideally, the TRAPPIST-1 system's proximity to Earth would allow scientists to better understand how dwarf planets, asteroids, satellites, comets and circumstellar disks form and interact with each other.
A platform to better understand the atmosphere
In many ways, because this discovery will help us understand other planets in the universe, it will also help us understand their atmospheres, which makes sense.
It is important to remember that these are the first terrestrial-sized planets to be discovered orbiting a particular type of star at the "correct" distance. This means that their atmospheres will provide us with important information about other planets like these, which, in turn, will allow us to better analyze the chemical signatures that water, methane, oxygen, ozone and other components leave in the planet's atmosphere.
TRAPPIS-1 provides "one of the best opportunities for the next decade for studying atmospheres around Earth-sized planets," says Nicole Lewis, an astronomer at the Space Telescope Science Institute in Baltimore, Maryland.
Scientists will also study the temperatures and pressures at the surface of planets, which will greatly help in determining their suitability for life.
All these planets can be with water
When looking for signs of extraterrestrial life forms on distant planets or other celestial bodies, scientists almost all start with a simple test: is there, can water be present on this body?
And while some planets like Mars and Venus are believed to have once had liquid water on the surface, the lack of ozone with other protective elements leads scientists to believe that any possible life that could form is already dead - because it cannot survive cosmic radiation sterilizing the surface of planets.
Although there is a possibility that liquid water will be found on all seven planets in the TRAPPIST-1 system, the chances of finding water (and therefore life) will be higher for three planets located in the potentially habitable zone - where it will not be too hot and not too cold for liquid water to remain, flowing into lakes, rivers and oceans.
ILYA KHEL