O PLANETA QUE PODE SER MELHOR QUE A TERRA - ROSS 128b

Earth may not be the best planet for life; I know this idea sounds absurd. Finally, our world has oceans, a breathable atmosphere, and relatively stable temperatures. billions of species scattered across practically every imaginable environment. For a long time, we believed that finding life elsewhere would mean finding a perfect copy of our planet, another Earth orbiting another sun, but there exists one A much more intriguing possibility, perhaps nature can do better; don't take me seriously A mal, the Earth is simply perfect in every aspect, but the idea here is to make A question: are there worlds where certain conditions remain favorable? for a much longer life, orbiting stars that survive hundreds of billions of years? Well, one of these worlds might be surprisingly close to us—just about 11 years ago. Before the lights of Earth, there is a small red star called Ross 128, orbiting extremely close to her is a planet known as Ross 128b, whose year lasts less its star is much smaller, cooler, and redder than the Sun, with an orbital period of 10 Earth days. and looking only at these characteristics, this seemed to be just one of the thousands of strange worlds scattered across the galaxy, but when astronomers began to analyze Pay closer attention to this system, and you'll notice something extraordinary. I'm TH, and before we travel more than 11 light-years, I ask that you subscribe to the channel. Turn on the bell to receive all notifications, don't forget to like and leave a comment In the comments, share your opinion and suggestions for future videos. For decades, finding a planet like Ross 128b would have been practically impossible. He is relatively close in cosmic terms, but even so, he remains completely lost in the glow of your star, we cannot see continents, oceans, or its surface, In fact, astronomers discovered this world without ever seeing it directly, and everything began by observing a movement so small that it would have been impossible to perceive without instruments extremely precise, the discovery was announced in 2017, following years of observations conducted with ARPS, an instrument installed at the La Silla Observatory in Chile, unlike Many exoplanets discovered by the transit method, Ross 128b was found through from a well-known technique called radial velocity, the idea may seem strange, but it is relatively Simple: when we imagine a planet orbiting a star, we usually think of the star completely stationary, while the planet rotates around it, but that does not happen exactly Thus, the planet's gravity also pulls on the star; as a result, both bodies we perform a kind of gravitational dance around a common center of mass, in In the case of a small planet, this stellar motion is extremely subtle, still Thus, instruments such as ARPS are able to detect it by analyzing minor alterations. in its light, when the star approaches us, certain lines in its spectrum they shift slightly toward shorter wavelengths, whereas when moving away, the opposite occurs on the contrary, by observing this pattern repeatedly, astronomers are able to detect the presence discovered an invisible planet and estimated some of its characteristics, thus Ross 128b began appearing in the data, and the observations indicated a planet with a minimum mass of just superior to Earth, orbiting its star at a distance of only about 7 million million kilometers, for comparison, Earth is about 150 million kilometers away than Sol, Ross 128b is therefore more than 20 times closer to its star than As a result, it completes a full orbit in just 9.9 days. terrestrial, at first glance, this seems to eliminate any possibility of an environment pleasant, a planet so close to a star should be extremely hot, but Ross 128b is not the Sun; it is much smaller, cooler, and far less luminous, which means so that its planet needs to remain incredibly close in order to receive a significant amount a planet, but also a potential candidate for hosting life, and when scientists realized this, Ross 128b ceased to be just another a small planet discovered in the galaxy, because the true secret of that world It was precisely on the star that shone above him. When we think about the possibility of life on another planet, we usually look first for the world itself, its temperature, size, atmosphere, or even the presence of water, but There is nothing more important than this: no planet chooses its destiny on its own, its The star may determine whether it remains habitable for billions of years or loses its atmosphere. and it will turn into a desert, and precisely here is where this exoplanet begins to become Really interesting, Ross 128 is a red dwarf, as we've seen, a very small star smaller, cooler, and less luminous than the Sun, stars of this type are extremely common in the Milky Way and possess an impressive characteristic: they consume their fuel in such a slow manner that they can remain active for absurdly long periods of stars like the Sun, this means that, in theory, planets around them could rely on a relatively stable energy source over gigantically long timescales, But just as everything in the universe has a problem, many red dwarfs have a prolonged youth. extremely violent, and some continue producing powerful stellar eruptions, for a planet that needs to orbit very close in order to receive sufficient heat, this It can be devastating; frequent explosions can bombard its atmosphere with radiation. energetic particles over billions of years, making it difficult to maintain conditions favorable to life, Proxima Centauri, our nearest stellar neighbor, is an excellent an example of this challenge, your planet Proxima B is extremely interesting, but it lives in a star known for exhibiting intense activity, however, Ross 128 appears offer a different scenario, observations indicate that it is a relatively quiet and little active, especially when compared to many other red dwarfs in the Milky Way, and this could make a huge difference for Ross 128 b, even while orbiting just a few million kilometers away, the planet may face an environment less aggressive than we would find around other similar stars, this it does not yet mean that its surface is habitable, Ross 128 b is probably so close to its star that it may exhibit synchronous rotation, maintaining approximately the same side facing her, although this has not yet been confirmed, moreover We do not know how much of its atmosphere might have survived the star's more active past. but there is a fascinating possibility hidden within this system, as the Sun will continue to grow its brightness will render the Earth uninhabitable in the distant future, a small red dwarf How can Ross 128 continue to exist for trillions of years, and if Ross 128 b managed to to preserve an atmosphere and water throughout its history, perhaps it received something extremely precious, time, billions of years for an environment to stabilize, billions years for chemical processes to become increasingly complex, and perhaps time enough for something extraordinary to happen, but to find out whether this is truly possible, We must finally look to the planet. After getting to know the star, we can finally try to imagine the world that orbits around it, And here there is an important detail: Ross 128 b remains practically a planet. invisible to us, we do not possess photographs of its surface, we do not know it directly its atmosphere, and we don't even know for sure what its radius is, all we can do to gather the available clues and discover which types of worlds are compatible with What we observe, one of the most important pieces of information comes precisely from its discovery, Measurements indicate that Ross 128 b has a minimum mass slightly greater than that of Earth. making it quite plausible that it is a rocky planet; moreover, despite due to being extremely close to its star, it receives only a moderate amount of energy, precisely because its star is much less luminous than the Sun, this places the planet near the region where, depending primarily on its atmosphere, temperatures habitability with liquid water could exist, and this atmosphere is the key element What's missing in this puzzle, if Ross 128 b has a sufficiently dense atmosphere? it could transport heat across the planet and reduce extreme temperature differences, this would be especially important because, as we have seen, its extremely short orbit makes it possible that he is gravitationally locked to the star, in this scenario, the hemisphere would remain constantly illuminated by a small reddish sun, while the other would face a practically eternal night, between the two, there would exist an enormous region of transition, where the star would remain near the horizon, depending on the circulation atmospheric, precisely these areas could exhibit some of the most interesting conditions from the planet, but there is another completely different scenario if Ross 128 b lost its atmosphere during the most turbulent phase of its youth, its surface could have been just an immense rocky desert, with brutal temperature differences between the illuminated side and the dark side, unaware of its atmosphere, leaves both extremes possible, and It is precisely this that makes Ross 128 b so fascinating—we are talking about a planet relatively close, with a mass similar to Earth's, orbiting a surprisingly calm and receiving a quantity of energy that allows imagining much more elaborate scenarios interesting, we still cannot assert that oceans, clouds, or any form of life in that world, but if some of these pieces are in the right place, Ross 128 And it could be much more than just another rock lost in space, and that leads us The question that truly matters is whether a planet like this could, in some respects, offer conditions for life even more enduring than the Earth itself? Throughout our entire search for life in the universe, we make an almost automatic assumption, Earth would be the perfect model of a habitable planet; we are searching for worlds of our own size, temperatures similar to ours and stars similar to the Sun, but there is a problem in this logic, the Earth does not need to be the best possible planet for life, it it is simply the only inhabited planet we know of, and some researchers already they work with a fascinating idea: there could exist super habitable worlds, where certain conditions be even more favorable to life than those found here, this it does not mean that Ross 128 b is officially classified as one of those worlds, in fact we still know too little about him to make that statement, but some of his characteristics allow for interesting possibilities; moreover, as we have seen, there exists An extraordinary advantage of living around a star like Ross 128 is time, the sun is about 4.6 billion years old, and it will not remain as it is forever, its brightness will continue to increase slowly, and long before it transforms into a red giant, Earth will likely cease to offer the pleasant conditions we know Today, red dwarfs, on the other hand, consume their fuel much more slowly, and can remain active for immensely longer periods, if a planet manages to survive the most turbulent phase of these stars' youth, and preserving an appropriate atmosphere, He could, in theory, achieve stability over extraordinarily long timescales. It is here that Ross 128 b becomes special—perhaps it does not have forests, oceans, not even a significant atmosphere, it could just be a barren rock orbiting a small Red star, we still don't have sufficient evidence to know, but there is another scenario, if Ross 128 b is rocky, has preserved an atmosphere, possesses water, and can sustain the heat received from its star, we might be facing an entirely different environment than Earth, yet still capable of remaining habitable for an immense period of time, a world where stability would not be measured merely in billions of years, but potentially, far beyond that, perhaps, a better Earth does not mean having more beautiful beaches, pleasant temperatures, or an atmosphere identical to ours, perhaps, simply means offering life, what it most needs to evolve, adequate conditions, and an almost unimaginable amount of time. For a very long time, our search for life in the universe has been guided by a a fairly simple idea: finding another Earth, a blue planet orbiting a star similar to the Sun So, with oceans, continents, and familiar conditions, it makes sense, after all, even until today, This is the only inhabited world we know of, but Ross 128b forces us to reconsider A much more interesting possibility, perhaps life does not need a second Earth. Perhaps there are completely different ways to build a habitable planet, Ross 128b, completes one year in less than 10 Earth days, orbits extremely close to a small red star, and likely experiences conditions very different from our own, Still, some characteristics make this system fascinating; its minimum mass is similar on Earth, its star is relatively calm, and the amount of energy reaching the planet, imagine scenarios in which, under appropriate atmospheric conditions, liquid water could exist on under certain conditions, even more importantly, Ross 128 belongs to a class of stars capable despite surviving for extraordinarily longer periods than our Sun, however, We must make one thing very clear: we still don't know whether Ross 128b is habitable, we don't know whether has oceans, an atmosphere, a magnetic field, or any form of life, and therefore, also not We can assert that if it has even the slightest potential to support life, perhaps it's merely an immense landscape. rugged and stereoscopic, marked by billions of years of exposure to the environment of its star, however, There's something extraordinary about this uncertainty—Ross 128 is only about 11 light-years away. and continues slowly approaching our region of the galaxy, in approximately 71 In a thousand years, this star will pass at a distance of slightly more than six light-years from the solar system, in other words words, on cosmic scales, this small world is practically a neighbor, perhaps future ones future generations will be able to analyze its atmosphere, and finally discover what exists on that planet, Perhaps they will find only a silent rock, perhaps they will find signs of water, or in the possibility most extraordinary of all, perhaps they will discover that life found a way in that world entirely different from the one followed on Earth, and if this occurs, Ross 128 b could teach us one of astronomy's greatest lessons: our planet does not need to be the perfect model of the universe, Earth might simply be one among countless ways in which nature creates a world where life can thrive, basically Ross 128 b has two options, either it looks like Terra, or, as it happens, Mercury, and look at this coincidence—it's precisely about the planet closest to the Sun. as I mentioned in the last video, there we'll conduct a mental experiment, and we'll try to imagine how would be a crewed round-trip mission to Mercury, a journey where the greatest challenge would not it's not the planet itself, but rather our own star; to verify, just click on the video that's there appearing there on the screen.