Where is the exoplanet of proximal b. What you need to know about Proxima B - the closest habitable planet to us? Search for new worlds

The new planet orbits the star Proxima Centauri, which is four light years away. "This is not only the closest Earth-like planet to us, it is probably the closest planet to us outside the solar system, since there are simply no stars closer to Proxima Centauri," he said at a press conference of the magazine Nature one of the study participants Ansgar Reiners from the University of Göttingen in Germany.

Astronomers found hints of a planet in data from the European Southern Observatory back in 2000, but it took them more than 15 years to confirm their discovery. The planet was discovered by the Doppler method: revolving around the star, the planet pulls it towards itself, because of this, the star all the time moves a little towards the Earth, then moves away from it. As a result, the spectrum of the star's radiation, which telescopes on Earth catch, changes.

Temperature on the planet

The star Proxima Centauri is a red dwarf, smaller than the Sun - only 12% of the Sun's mass - and much fainter - just 0.15% of the Sun's brightness. The mass of the planet Proxima b is 1.3 Earths. Researchers believe it is a terrestrial planet. It is much closer to its star than the Earth is to the Sun. The distance between them is 7.5 million kilometers, which is 20 times less than from the Earth to the Sun. It takes 11.2 days to orbit the star Proxima b.

Alpha Centauri AB and Proxima Centauri. Photo: Digitized Sky Survey 2 Acknowledgment: Davide De Martin / Mahdi Zamani

“Based on this information, we can calculate the temperature of the planet's surface, if we do not take into account the atmosphere - minus 40 degrees Celsius. Without the atmosphere, the Earth's temperature would be similar - minus 20 degrees, ”explained Reiners.

Water, life, atmosphere

There may be liquid water on Proxima b, however, whether it is actually there is not known for sure and depends on the history of the formation of the planet and the activity of its star. The ages of both are comparable to the ages of the Sun and Earth, respectively. However, speculation about their history is still an area of ​​pure speculation.

Perhaps the water and the atmosphere were at first, and then they were gone, because the atmosphere was carried away by the stellar wind of Proxima Centauri. However, we do not know how active the star has been in the past. Perhaps the planet was protected from the stellar wind by a magnetic field, just as the Earth's magnetic field protects our planet from the solar wind, but we do not know if Proxima b has it. Maybe the planet first lost its water and atmosphere, and then, like the Earth, survived "" by comets, which again brought water to it. In general, there are many scenarios, and what actually happened and is happening on the planet will become clear in the process of further research.

However, if the atmosphere and water are found, this does not mean that the conditions on the planet are so comfortable. “Proxima b receives more X-ray and ultraviolet radiation than Earth. If we on Earth received such a dose, it would affect life, although I am not sure that living organisms would become extinct completely, ”said Reiners.

Planet exploration

Earth-like planets outside the solar system have been found more than once. However, "this planetary system is much closer to us than any other, and this greatly facilitates its detailed study," Reiners emphasized.

It is possible to establish whether a planet has an atmosphere if it is at some point in its orbit between its star and the Earth. Then the atmosphere can be seen thanks to the backlighting. But whether there is such a position in the orbit of Proxima b, we do not yet know, and the chances of this are not very high. Another possibility is to catch

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Hello inhabitants of Proxima Centauri!

Yes, you read that correctly. You are at the moment, you are not on Earth, you are on the planet, which is known to you as Proxima Centauri b. Moreover, now the beginning is not the twenty-first century, as you think, but the thirty-first. But first things first. By the end of the third millennium, humanity has finally managed to break out of the solar system, creating ships capable of covering interstellar distances, within an acceptable time frame. In the middle of the thirtieth century, the colonial spaceship "Procyon" was created as the target, the Centauri system was chosen, namely, the planet Proxima Centauri b, discovered at the beginning of the twenty-first century, since the planets near red dwarfs were considered the most suitable for life, as the most durable. The Procyon departed at the appointed time, taking on board the colonists and supplies for the flight.

However, shortly before the departure of the Procyon mission, an unmanned robotic ship was sent to the Proxima Centauri system, which was launched by a group other than the one that was implementing the project to colonize the surrounding stars. This group did not trust the data obtained from space telescopes and believed that it was necessary to conduct a direct reconnaissance before sending people. As it turned out later, it was this group that turned out to be right.

The robot ship arrived on the planet Proxima b and sent to Earth, disappointing information. As it turned out, the planet was categorically not suitable for colonization: being too close to its dim star, it was trapped in tidal resonance, as a result of which it could not rotate. Thus, the day side was red-hot, like Mercury, and the day side was terrifyingly cold. As a result, the planet's atmosphere and hydrosphere had long flowed to the night side and Proxima b also froze there, it was a lifeless and airless regolith ball.

Unfortunately, it was no longer possible to deploy the Procyon and send it back - it would not have enough fuel for repeated acceleration, up to relativistic speeds, only for braking. Therefore, it was decided to implement the long-standing project PlanetGrid, which provides for the transformation of the surface layer of the planet into a mass of nanocomputers that form a single computing environment. They already wanted to do this on some dwarf planet, but such experiments in the solar system were prohibited. Fortunately, the equipment for such an experiment was prudently placed aboard the robotic ship. On the resulting planetary supercomputer, it was planned to deploy a full-fledged virtual simulation, in which the Procyon colonists had to wait for the rescue starship. Everything went fine at first. Procyon arrived at the Proxima Centauri system and found a ready-made simulation. And our rescue mission on the Polaris starship soon started from the solar system. Years later, when we were still halfway to the goal, we were overtaken by a message that communication with the Procyon was interrupted.

When we arrived at the planet Proxima b, we found that it was covered along the terminator line by a thick layer of computronium - intelligent matter consisting of nanomachines. And - no trace of Procyon. We connected wirelessly from orbit to this computational mass and found a simulation that recreates the early twenty-first century. I will not bore you with details. As we eventually found out, Procyon, for some reason, boarded Proxima b and was absorbed by the planetary supercomputer, and its crew was subjected to artificial amnesia and replacement of memories, so that its members began to consider themselves people who lived a thousand years ago. in the twenty-first century. Obviously, there was some kind of targeted sabotage, the motives, goals and executors of which, however, are not yet clear to us, perhaps the group that launched the robot reconnaissance ship and created the Computronium was pursuing malicious goals from the very beginning. As for the Procyon crew, you are the astronauts! It was for you that this simulation was created and became your prison.

We can evacuate you and return you to Earth, but first we need to find you. And for this, you need to remember that you are not residents of the twenty-first century, you are astronauts of the thirty-first century. Of course, not everyone you see around you - your companions on this space travel, most of the "people" inhabiting this simulation are just program-controlled characters, NPCs. That is why we are posting this text on all the network resources on which we can: numerous bots will write that this is just trolling and fake, but if you are a real person from planet Earth, then the text should certainly evoke some kind of response in your soul, making repressed memories vaguely stir. Real memories, as opposed to suggested ones.

We do not know exactly what dangers the PlanetGrid simulation may pose, so we created a special network application that acts as a secure communication channel through which we will try to help you remember everything. Downloading the program is a test, the successful completion of which will prove that you are a real person, a member of the Procyon crew. We also assume that the pseudo-human NPCs inhabiting the simulation in abundance may try to prevent us by arranging provocations and stirring up the water. Don't get fooled and don't give in.

Download our app, you can [DATA EXPUNGED]

MOSCOW, 24 Aug - RIA Novosti. European astronomers have discovered near our closest star, Proxima Centauri, an Earth-like planet the size of Earth, on the surface of which life could potentially exist, according to an article published in the journal Nature.

“From a statistical point of view, the probability of error in this case is extremely small - one chance in 10 million or even more. This is always possible, but it is highly doubtful that this is so in this case, "- said Guillem Anglada-Escude from Queen Mary University in London (UK), answering the questions of RIA Novosti.

Ghost planet

The Alpha Centauri star system, the closest family of stars to us, consists of two luminaries similar to the Sun - Alpha Centauri A and Alpha Centauri B, and the red dwarf Proxima Centauri. Proxima is the closest star to the Sun. It is about 4.24 light years from Earth, about 0.2 light years closer than stars A and B.

In 2012, the scientific world was shocked by an amazing discovery - an earth-like planet was discovered near the star Alpha Centauri B by small "swings" in the spectrum of the star, which were caused by gravitational interactions between the exoplanet and the star. In October 2015, British astronomers discovered that this planet did not actually exist, and that the signal of its existence was generated by the peculiarities in the operation of the HARPS instrument with which it was discovered.

For this reason, Anglada-Escudé and his colleagues were in no hurry to announce the discovery of a planet near Proxima Centauri, an even more difficult star to observe due to its small size and restless disposition, which often gives rise to similar "ghosts" of planets in the data of observations of its spectrum and brightness. Scientists announced their discovery only after six months of continuous observations of the "swing" of the spectrum of Proxima Centauri and the study of archived data over the past 16 years.

Earth's closest cousin

This planet, which has not yet received its own name and is modestly called Proxima Centauri b, is very similar to Earth in its size and properties. In particular, its diameter is only 1.2 times that of the Earth, it is located inside the so-called "zone of life", in orbit where water can exist, and its average surface temperature is minus 40 degrees Celsius. It receives about 65% of the energy that the Earth "gives" from the Sun.

Scientists do not exclude the possibility that it may have a thick atmosphere and significant reserves of water, which makes it the closest candidate for the role of a full-fledged "twin" of the Earth. Such an idea, as planetary scientists admit, has several potential obstacles.

The first of them is Proxima Centauri itself - the planet revolves around this star in a very close orbit - it is 20 times closer to the star than the Earth is to the Sun, and makes one revolution in just 12 incomplete days. For this reason, flares on the surface of Proxima, a restless star, will have a much stronger effect on the state of the planet's atmosphere and on its viability.

Secondly, the current position of Proxima Centauri b does not yet allow us to understand whether it is more similar to Earth, or to Venus - similar in size and position of the planet, radically different in climate and atmospheric composition. In addition, the planet can constantly "look" with one side at the star, as a result of which it will be even more unfit for life than Venus.

In any case, the answers to all these questions can only be obtained after launching more powerful telescopes than those that exist today, or sending a probe to this planet.

If you were not on Earth on Wednesday, then you missed the following: astronomers found a planet that is as close to us as possible - in the nearest star system Alpha Centauri. A planet called Proxima Centauri b completes a circle around its star every 11.2 days. And yes, it is in the "potentially habitable zone," the Goldilocks zone, where liquid water can (for now only) be on the surface. Its mass - 1.3 Earths - implies that the planet must (for now only) be solid. No wonder we have already listed it as one of the greatest discoveries of the century.

But wait a minute. Astronomers have found other terrestrial planets in habitable zones in recent years. According to the Planetary Habitability Laboratory at the University of Puerto Rico, 15 potentially habitable exoplanets of "terrestrial size" (in terms of mass or radius) have now been confirmed. And although yes, Proxima Centauri b has a mass well ooooo very close to that of the Earth, in other properties it may not be so earthy.

What really sets this planet apart from the competition and what attracted attention in the first place is its location. Just as the closest supermarket to your home will become the most visited store for you, Proxima Centauri b warms the souls of scientists with its closeness and attractiveness. However, this attractiveness is still questionable.

First, scientists so far only know the minimum mass of Proxima Centauri b - the smallest mass that it can have - and do not know its radius. That is, they do not know for sure whether it is solid or not.

“Don't forget that we only have the minimum mass of this planet,” astronomer Elizabeth Tasker tweeted. "By that measure, I will be the twin of most life on Earth."

In addition, the star covers the planet with high-energy radiation, which means that it has dried up all the water a long time ago. If there is at least some hydration, it will be only in the most sunlit places. While “warm enough to have water” is an important fact, it cannot be equated with actual habitability.

Rory Barnes, an astronomer at Washington State University, has developed the Habitability Index, which evaluates potentially pleasant planets based on a large number of nuances. And his findings are disappointing. “I am pessimistic that any planet can be habitable because there are too many requirements to be met,” he says. "But Proxima gives us a great chance to find out if I'm right or wrong."

In light of all this uncertainty, the excitement, or as it is now fashionable to call it - hype, about this planet seems premature or just downright wrong. But there is definitely a hype.

“I was surprised when I read an article from the European Southern Observatory, which was very clear: this is the most Earth-like planet we have found so far,” says Lisa Messeri, an anthropologist at the University of Virginia, “despite the fact that in in the same article, they wrote that the planet has no seasons, the year lasts 11 days, the sky should be red, and Proxima Centauri is an active star with solar flares. In other words: this is generally an uninhabited world. "

Messeri does not study exoplanets. She studies people who study planets - follows them and interviews for many years. The reaction to this discovery, she says, has more to do with Proxima's proximity to us. "The reason we care about this planet is because it is a place that we can go and be." In the case of most planets, we can only imagine. But Proxima Centauri b is the first exoplanet that could be physically reachable.

Earth's geography influences our perception in a similar way. “We feel connected to places that are close to us because we can go there on the weekend,” says Messeri. "Even if I'm not going to New York on Saturday, the fact that I can makes it a part of my world."

Forward and with a song

While scientists are not going to Alpha Centauri on Saturday, they definitely intend to fly there. Breakthrough Starshot Initiative about which was announced in April, plans to send probes the size of a postage stamp to the star. At the time of Proxima's announcement, the people behind the project had not yet determined which of the stars in the triple system they want to visit (but now the choice is almost obvious).

However, it is too early to discuss interstellar space travel - in the sense of seriously discussing it. Scholars try to stay away from such discussions. But now there is a reason and a place to point to, says Messeri. With such a place, scientists can speak publicly about interstellar intentions with fairness and passion.

The proximity of the new planet also makes the search for alien life more warranted. There is a real star, a real earth-like planet, really nearby. If a Contact-style signal came from this system, one could bet a million dollars that the world's governments would unite and send people there. Because interstellar travel with humans to Proxima is the space version of Messeri's weekend trip to New York.

Sending an interstellar message to aliens instead of waiting for it to be received has historically been considered a philosophical exercise. A message can travel many generations to its destination, as well as a hypothetical response. But with Proxima, we get something like a real conversation with aliens, like meeting a stranger, says Douglas Vacoch, head of METI International. "In less than ten years, we could send a message and get a response from interested Centauri."

More traditional sciences will also participate in sharing the benefits: for example, the European extremely large telescope will be able to take pictures of this planet, which will provide at least a little new information (maybe a lot). It will allow scientists to find possible biosignatures indicating the existence of life. Scientists go crazy at the thought of such a possibility, because the closer the planet, the more information we can learn about it.

Looking in the mirror

And yet it's not Earth's twin, no matter what the headlines say, and scientists have yet to find Earth's twins. Hot Jupiters are cool; planets with glass rains also amuse; super-earths are generally supernatural. Compiling a complete census of exoplanets will be a very valuable asset. But most scientists, according to Messeri, really just want to find another Earth. This is reflected in scientific priorities. The Kepler Space Telescope, which has found more planets than anyone else on this planet, was "specially designed to explore part of our region of the Milky Way galaxy in search of dozens of Earth-sized planets in or near the habitable zone," according to NASA.

The search for an "Earth twin" is a quest for a platonic ideal, says Messeri. "It allows us to see the Earth in its prime, as we would like to see it, which is not disfigured by climate change, war or disease."

But we haven’t found such a place yet. And we may never find. In your quest to find the perfect match, you usually find someone who is super cool but yells at you when hungry or hates your mom. In your search for the perfect job, you find yourself in the role of a dishwasher. In this sense, the discovery of Proxima Centauri b is a representation of humanity's striving for perfection, for a pure and virgin Earth.

Most likely, this will happen all the time. We set ourselves a great goal and failed. Not because we are so unlucky, but because we were doomed to it from the very beginning, because this is the nature of humanity: to always strive for the ideal and never achieve it.