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The space eye of Sauron

When the first image of the black hole, M87*, was released, several memes circulated online that repositioned the photo in different contexts. One of the best known was the one that placed M87* in the center of Sauron's eye as it was displayed in Peter Jackson's The Lord of the Rings trilogy.
The photo I present above, however, taken in 2008 by the Hubble Space Telescope is much more reminiscent of the evil eye of Sauron. It represents the debris disk around the star Fomalhaut, a white star in the constellation of Piscis Austrinus approximately 25 light years away. In 2008, an exoplanet was also discovered, Fomalhaut b (also known as Dagon, a perfect name for Halloween parties!), although there are still doubts about its existence (probably it does not exist, at least not yet).
The curiosity about this star is that the protagonist of Stanislaw Lem's Return from the Universe returns to Earth after a space exploration trip right around Fomalhaut: the book is dated 1961, almost fifty years before astronomers discovered clues about the possible existence of Dagon.

Total's responses to global warming

Building upon recent work on other major fossil fuel companies, we report new archival research and primary source interviews describing how Total responded to evolving climate science and policy in the last 50 years. We show that Total personnel received warnings of the potential for catastrophic global warming from its products by 1971, became more fully informed of the issue in the 1980s, began promoting doubt regarding the scientific basis for global warming by the late 1980s, and ultimately settled on a position in the late 1990s of publicly accepting climate science while promoting policy delay or policies peripheral to fossil fuel control. Additionally, we find that Exxon, through the International Petroleum Industry Environmental Conservation Association (IPIECA), coordinated an international campaign to dispute climate science and weaken international climate policy, beginning in the 1980s. This represents one of the first longitudinal studies of a major fossil fuel company's responses to global warming to the present, describing historical stages of awareness, preparation, denial, and delay.
Bonneuil, C., Choquet, P. L., & Franta, B. (2021). Early warnings and emerging accountability: Total’s responses to global warming, 1971–2021. Global Environmental Change, 102386. doi:10.1016/j.gloenvcha.2021.102386

Rewind a black hole story


Glass bubbles from black hole
In terms of the length of human life, we can conclude that this is a bit impossible to reconstruct the story of a particular star. Observing all the star in the universe we can create a model about their evolution, but we observe with a great details cosmo only since a century or so. Now, thanks to a particular device, the LoFar, Low Frequency Array, a team of astronomers collected data about the last 100000 years of the black hole at the center of Nest200047.
LoFar is a radiotelescope that collects radiation produced by the oldest electrons that are in the neighbour of a cosmic object. In this way researchers can go literally back in time along the story of Nest200047*.
During its phases of activity, the black hole devours the surrounding material and in this process releases a large amount of energy, sometimes even in the form of jets of particles that move at the speed of light and emit radio waves. These jets generate bubbles of particles and magnetic fields which by expanding are able to heat and move the intergalactic medium that surrounds them, enormously influencing its evolution and therefore the rate at which stars are formed.

Butterflies, hurricanes and... pools!

Chaos is nothing more than order seen from the opposite side.
This defintion by Fethry Duck in the italian story Il mobile caotico (The chaotic furniture) can be considered very centered on the heart of chaos. And the mathematical tool that we used to study it is the theory of chaos.
Flapping the wings
What best identifies chaos theory is the butterfly effect, which identifies in a simple and effective way the strong dependence of chaotic systems on initial conditions. The name was first used by Edward Lorentz, who published the first article on this effect in 1963(1).
The popular version of the butterfly effect goes something like this: The flapping of a butterfly's wings in Brazil causes a hurricane in New York and the use of the butterfly was probably suggested to Lorentz from Ray Bradbury's 1952 short story A sound of thunder in which an unwary time traveler, stepping out of the path set by the travel agency and thus stepping on a butterfly, even manages to change the result of the last US presidential elections, allowing a fascist to become the most powerful man on the planet!
From a scientific point of view, one of the most typically chaotic problems is that of weather forecasts, because of the large amount of variables that are present. The appearance of chaotic behaviors, however, would not be so scientifically interesting if it were not for one of their particular characteristics: the fundamental laws that govern, for example, time are deterministic and individually easily solved, but by combining together a large number of such equations, not only the resolution of the system is more complicated, so much so that it is necessary to use electronic calculators, but also the solution shows a chaotic behavior graphically well identified by the Lorentz attractors:

42: A family portrait

No, this is not the towel day, but what ESO released yesterday is undoubtedly something quite useful for any space tourist: a series of 42 detailed images of the largest asteroids in the solar system.
The main asteroid belt, located just beyond the orbit of Mars, is made up of rocky objects of various sizes, reaching up to 200 km in diameter, without forgetting the largest of all, Ceres and Vesta, respectively 940 and 520 kilometers in diameter. The family portrait of the 42 asteroids was made using the Very Large Telescope:

Nobel Prize in Chemistry 2021: A scent of Feynman

One of the most famous speech by Richard Feynman is There's plenty of room at the bottom:
Now comes the interesting question: How do we make such a tiny mechanism? I leave that to you. However, let me suggest one weird possibility. You know, in the atomic energy plants they have materials and machines that they can’t handle directly because they have become radioactive. To unscrew nuts and put on bolts and so on, they have a set of master and slave hands, so that by operating a set of levers here, you control the “hands” there, and can turn them this way and that so you can handle things quite nicely.
The idea is to manipulate molecules to build, for example, an electric engine, or a book, or something else. The most curious fact about the Nobel Prize in Chemistry 2021 is that Johan Jarnestad has illustrated the work of Benjamin List and David MacMillan using a couple of workers, an image that, in a particular way, is very similar to Feynman's idea.
Building molecules is a difficult art. Benjamin List and David MacMillan are awarded the Nobel Prize in Chemistry 2021 for their development of a precise new tool for molecular construction: organocatalysis. This has had a great impact on pharmaceutical research, and has made chemistry greener.
I hope to write soon an article about Feynman and miniaturization obviously from the physics point of view.
Stay tuned!

Giorgio Parisi: A Nobel for complex systems

The last time an italian was awarded the Nobel Prize in physics was in 2002: Roberto Giacconi for his pioneering research in the field of X-ray radiation from the universe. Another italian research that probably could win the Prize was Adalberto Giazotto, who designed the VIRGO interferometer, that with LIGOs shared the first observation of gravitational waves. The Swedish Academy decided to assign the Prize to three of the LIGO's founders, Rainer Weiss, Barry Barish and Kip Thorne. But this is not a great problem: after all, the Nobel Prize serves to emphasize personal contributions, but also to establish key points in the knowledge, and in this sense, the role of Italy had already been indicated as fundamental.
Today, however, a long-awaited award arrives: Giorgio Parisi, theoretical physicist, whose works have provided important contributions to field theory and statistical physics, won the Nobel Prize in physics
for the discovery of the interplay of disorder and fluctuations in physical systems from atomic to planetary scales