(ORDO NEWS) — Despite the fact that 2020 can be called the year of scientists fighting the coronavirus, interesting and significant discoveries have been made in other areas of science. These include a new way to predict the structure of proteins, the detection of traces of life on Venus and a partial disclosure of the secret of powerful radio flares in the Universe. “Lenta.ru” publishes a dozen breakthrough scientific studies not related to the study of SARS-CoV-2.
The greatest mystery of biology
Scientists have already learned to determine which parts of the genome are responsible for protein synthesis. Thanks to the genetic code, from the DNA nucleotide sequence, it is possible to unambiguously determine the amino acid sequence in a protein, called the primary structure. However, the protein must fold into a three-dimensional structure capable of performing certain functions. This folding process, called folding, depends on the chemical properties of the amino acids. To determine the functions that a protein with a given amino acid sequence can perform, researchers most often resort to experiments. Even if the three-dimensional structure can be predicted using algorithms, there is a high probability of error.
Protein folding is recognized as one of the greatest problems in modern science. For each amino acid chain, in theory, there is a huge number of folding options, and inside the cell, as a rule, only one is realized. To create proteins with the necessary properties (for example, for anticancer drugs), you need to know what amino acid sequence is required for this and how it will fold.
To this end, scientists have developed a new artificial intelligence (AI) system DeepMind AlphaFold, which provides unprecedented accuracy in predicting protein structure. According to the test results, the average score for AlphaFold was 92.4 according to the Global Distance Test metric. At the same time, the score of 90 GDT is considered competitive among the results obtained experimentally. This means that AI is able, in many cases, to calculate the three-dimensional structure of proteins more accurately than using a number of laboratory methods.
Mysterious superconductor
Researchers at the University of Rochester have discovered the first superconductor at room temperature. Superconductors have zero electrical resistance, but this property only manifests itself at very low temperatures. In the new work, the scientists managed to achieve superconductivity at a record temperature of about 15 degrees Celsius. However, in order to do this, they had to subject the material of carbon, sulfur and hydrogen to an extremely high pressure of 270 gigapascals (which is 2.6 million times the atmospheric pressure on Earth). This pressure is characteristic of the center of the Earth, and this makes this superconductivity impractical.
Researchers do not yet know the exact structure of the resulting superconducting crystal. Even computer simulations have shown that a mixture of carbon, sulfur and hydrogen under extreme pressure should not have such a high superconducting temperature. However, the results of the study give hope that in the future a superconductor will be found at room temperature and much lower pressure.
Something from outer space
Inside a meteorite that fell to Earth 30 years ago, researchers have discovered for the first time traces of an extraterrestrial protein. Using mass spectrometry, scientists have identified the amino acid glycine bound to iron and lithium atoms. The simulation results showed that glycine was not an isolated molecule, but was part of a protein called hemolitin.
Although protein is structurally similar to earth proteins, it contains the hydrogen isotope deuterium. The ratio of deuterium and hydrogen is not typical for the Earth, but corresponds to long-period comets, whose orbit extends far beyond the orbits of the outer planets of the solar system.
Scientists believe that the protein formed in the protosolar disk more than 4.6 billion years ago. At the same time, the possibility remains that the molecule does not actually belong to proteins, but to a different type of polymer.
Disappeared matter
Astrophysicists have discovered the missing matter, which is 40 percent of the usual (baryonic) matter in the universe. Planets, stars and galaxies are composed of baryonic matter, but a huge fraction of this matter has remained undetected until now. At the same time, astronomers believed that it is contained in the Universe in the form of a diffuse gas, the radiation from which is too weak to be detected by conventional methods.
In the new work, scientists analyzed powerful bursts of radio waves from distant galaxies, or fast radio bursts (FRBs). FRBs last for several milliseconds and are accompanied by the release of a huge amount of energy into space – such as the sun has been emitting for several tens of thousands of years. Most researchers assume that this phenomenon has natural causes, such as supernova explosions, collisions of neutron stars, active black holes or magnetars.
Radiation from FRB travels a long distance (billions of light years) before reaching Earth. Passing through matter in the intergalactic medium, radiation is scattered. By the degree of dispersion, it is possible to determine the exact density of matter in space, which allowed the researchers to identify the missing substance. Although scientists do not know what exactly it is made of, it is assumed that they are clouds of hydrogen and helium atoms.
Radio source
Astronomers have found that the flare of the SGR 1935 + 2154 magnetar in the Milky Way is very similar in characteristics to fast radio bursts, whose nature is still unclear. Scientists have long assumed a link between FRB and magnetars – a type of neutron star with an extremely strong magnetic field – but so far there has been no confirmation of this.
Scientists have discovered the fast radio burst FRB 200428, whose source coincided with the location of an X-ray burst from the magnetar SGR 1935 + 2154, located in the Milky Way at a distance of 30 thousand light-years from Earth. Until now, astronomers have recorded only extragalactic fast radio bursts.
According to the theoretical model, the radio emission was the result of an ejection of plasma moving at a relativistic (close to the speed of light) speed and propagating in a magnetized environment rich in protons, neutrons and other baryons. The shockwave from the ejection generated synchrotron X-rays and gamma rays. In turn, this radiation, interacting with plasma ejections, contributed to the emergence of high-energy neutrinos. If scientists registered neutrinos, then this would be a confirmation of the model.
A feature of the SGR 1935 + 2154 magnetar was that it emitted radio waves, which made it possible to associate it with FRB, although these neutron stars usually emit X-rays and gamma rays. At the same time, the discovery does not exclude that other sources are possible for FRB.
Traces of life on Venus
Traces of phosphine have been found in the upper atmosphere of Venus. In this case, the poisonous substance is contained in quantities that cannot be explained by abiotic mechanisms, that is, processes in which living organisms are not involved. Scientists have identified phosphine using the ALMA radio telescope complex in Chile and the James Clerk Maxwell Telescope in Hawaii. On Earth, this substance is produced by anaerobic organisms that do not use oxygen for breathing.
It is known that phosphine is also found in the atmosphere of gas giant planets, but in this case it is produced by chemical processes that occur deep in their depths under pressure. Although it is unlikely that living organisms can survive on Venus due to the very harsh conditions, researchers do not yet know what other processes could lead to the accumulation of phosphine.
Scientists later demonstrated that a preliminary estimate of the amount of phosphine could be overestimated, but even the specified concentrations remain too high. According to experts, the discovery may stimulate new research on the second planet from the Sun.
Spots at Betelgeuse
In 2019, the red supergiant Betelgeuse suddenly dimmed, prompting rumors of the star’s imminent transformation into a supernova. Astronomers speculated that the star began to emit huge amounts of gas and dust, which eclipsed its bright surface and reduced its apparent brightness.
In 2020, scientists have identified the exact cause of Betelgeuse’s mysterious tarnishing. It turned out that the cause of the phenomenon was giant spots, similar to those of the sun, but many times larger. Astronomers analyzed data from 13-year observations of the red supergiant in the submillimeter range. During a 40 percent drop in apparent brightness from October 2019 to April 2020, the star also decreased its brightness at submillimeter wavelengths by 20 percent. Scientists examined models of radiative transfer and showed that the probable cause was temperature changes in the photosphere, that is, giant cold spots appeared on the surface of the star.
It was previously thought that dust emissions were responsible for the change in brightness. This phenomenon is typical for giant stars at the last stage of their life cycle. They swell, and the outer layers become unstable and begin to pulsate. As the gravitational pull on the surface of the expanding star weakens, pulsations can easily push gas, which cools, condenses and turns into dust. Although this dust obscures visible light from the star, it should emit radiation in the submillimeter range.
However, darkening at all studied wavelengths may indicate either a decrease in the average surface temperature of Betelgeuse by 200 degrees Celsius, or the emergence of relatively cold regions occupying 50-70 percent of the star’s surface.
The most powerful explosion
Astronomers at Northwestern University in the United States have recorded a new type of space phenomenon, which refers to fast blue optical transient (FBOT) – blue optical transient processes. Scientists are aware of only three such phenomena. In essence, it is a super-powerful explosion visible in optical, X-ray and radio beams.
The object that caused the explosion is located 500 million light-years from Earth. It generated an outflow of gas and particles that reached 55 percent the speed of light. It is known that gamma-ray bursts can do this, but they launch material whose mass reaches only one millionth the mass of the Sun. Scientists estimate that CSS161010 has accelerated to more than half the speed of light from 1 to 10 percent of the Sun’s mass. Based on this, the researchers believe that FBOT is the fastest transient process in the Universe.
Very close sun
The probe, developed by European scientists together with NASA, passed at a record close distance from the Sun. In the course of the first revolution around the star, the researchers managed for the first time to take pictures of dozens of small flares, called “solar bonfires”, which are several million times smaller than ordinary flares and are comparable to the size of Europa.
The device is able to withstand temperatures up to 500 degrees Celsius, which allows it to be at a distance of 40 million kilometers from the surface of the Sun. The devices are protected by a heat-resistant shell, which is exposed to solar wind, 13 times stronger than in Earth’s orbit.
The probe’s operators plan to slightly alter the trajectory of the Solar Orbiter so that it will receive images of the Sun’s poles for the first time in history. This will be done by 2027.
Ancient dust
The stardust found inside a massive meteorite that fell to Earth half a century ago is 7.5 billion years old, making it the oldest solid matter found on the planet.
The Murchison meteorite fell in Australia in 1969. In it, scientists have found dust granules older than the solar system, whose age reaches 4.6 billion years. The granules themselves were thrown into space by ancient dying stars, after which they were included in the composition of new celestial bodies.
First, the researchers crushed the fragments of the meteorite, after which the powder was dissolved in acid. The age of the granules was determined by assessing how long the substance was exposed to cosmic rays penetrating the solid material. When dust interacts with rays, new elements are formed, including neon isotopes, by the number of which the age of the dust was revealed. It turned out that 10 percent of the granules are older than 5.5 billion years, and 60 percent are between 4.6 and 4.9 billion years old.
According to scientists, the discovery indicates that the Milky Way is experiencing periods of increased star formation, one of which happened seven billion years ago.
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