Scientific results of the year

PublicPost recalls the main scientific events of 2012 - from the subglacial Lake Vostok to the Higgs boson, from the distant Denisovan man to nearby exoplanets.

For millions of years, the ice-covered Antarctic Lake Vostok remained deeply isolated from the rest of the world. It took Russian scientists thirty years of ice drilling in hellish conditions to reach a depth of 3,769 m for the first time - and the most inaccessible lake on Earth.

In the 1960s, when the first evidence of the existence of Lake Vostok appeared, heated debate broke out about whether its existence under many kilometers of ice was even possible. However, over time, the facts became completely convincing, and drilling began. The complexity of the work is difficult to convey: ice is a capricious substance, and the weather leaves only short summer months, so the work continued throughout January 2012 - and then the ice ran out.

For now, the well is mothballed so that in the coming summer, which is already beginning in Antarctica, we can take the first careful samples of the water of the protected lake. No one knows what kind of life might be found there.

The common truth has been debunked that only men are capable of constantly producing their reproductive cells, while women are already born with a certain set of eggs and then only spend it. This dogma, of course, applied to other mammals, but it turned out to be false.

Scientists obtained the first evidence that eggs continue to form in adult females in 2004 in experiments on mice. Then this data was not enough to overcome established ideas. However, in 2012, experiments with oocyte cultures obtained from human ovaries brought equally shocking results. It has been shown that there is one stem cell for about 10 thousand mature cells.

A piece of the phalanx of a girl’s finger, which miraculously reached us through tens of thousands of years, was enough for European geneticists to conduct a genetic analysis of the remains of an extinct species of people - Denisovan man.

Since 2008, Russian archaeologists have already found several fragments of bones belonging to representatives of this mysterious tribe in a cave in Altai. In mitochondrial DNA (the match of which serves geneticists as the most important marker of the proximity of species), Denisovan man differed from us in 385 positions - it turns out that he is almost twice as distant to our relatives as Neanderthals.

Already in 2012, a unique technique made it possible for the first time to conduct a full-fledged analysis of the nuclear, “main” part of DNA and discovered absolutely amazing things. In particular, it is shown that Denisovan people managed to interbreed with the ancestors of some modern peoples inhabiting Southeast Asia, leaving noticeable traces in their genome. The age of the remains found in Denisova Cave has also been clarified - between 74 and 82 thousand years.

DNA is just a tool for life: scientists have synthesized artificial xenonucleic acids and shown that they are capable of performing the same functions of storing and transmitting genetic information.

Theoretically, someday on this basis they can create full-fledged living organisms using a completely different biochemistry than is customary here on Earth. At least nothing fundamentally prevents this, and the first step has already been taken: in order to manipulate xenonucleic acids, biologists “modified” the enzymes of living organisms in a special way - and they successfully copied information from DNA to them or vice versa.

On the sixth, the most curious among us did not miss the chance to see for the last time a rare spectacle - the passage of Venus across the solar disk. The neighboring planet cannot cover any noticeable part of the Sun, and through the dark glass it appears as a black dot, slowly walking along the shining disk of the star. Everything took no more than six minutes - but the next time such an opportunity will appear only in 2117.

Collisions of protons accelerated by the Large Hadron Collider to near-light speeds made it possible to firmly announce the discovery of Higgs bosons for the first time. According to a theory proposed back in the 1960s, these exceptionally massive particles represent a field through which other particles gain mass.

They have been trying to get such a particle, or at least a hint of it, for a long time, by colliding other particles with each other. Such collisions generate a cascade of new particles, some of which last for fractions of a second, quickly decaying into other particles. Scientists monitored this process by colliding protons head-on, accelerated in the Large Hadron Collider to near-light speeds.

The first signs of the long-awaited discovery in the energy region of 125-126 gigaelectronvolts (which corresponds to a mass thousands of times greater than the mass of a proton) appeared in 2011, but only work in 2012 made them full evidence. Data collected by the collider's two largest detectors - ATLAS and CMS - provided sufficient statistics to confirm the reliability of the find.

Curiosity arrived on Mars, making a landing that shocked the whole world: having covered 567 million kilometers, the probe slowed down and smoothly descended exactly to the bull's-eye, so that the deviation from the ideal landing site was no more than 2 kilometers. Hundreds of thousands of viewers watched the dramatic event live on the Internet.

The minicar-sized vehicle represents the third generation of American Mars rovers and carries an unprecedented number of onboard instruments, including the Russian DAN neutron detector, designed to search for ice and water that may be hidden beneath the planet's surface.

Since then, Curiosity has gained thousands of followers on Twitter , updated its on-board software, turned on its instruments, and started moving. He observed a solar eclipse and found traces of an ancient stream. The DAN detector showed that there was several times less water in the soil than expected, and other instruments carried out successful mineralogical studies. The rock they encountered is very reminiscent of ordinary volcanic tuff, but the promised sensational discoveries have not yet been made.

By the way, the rover is powered by a radioisotope thermoelectric generator running on Russian nuclear fuel. The RD-180 engine installed on the Atlas-5 rockets, one of which sent Curiosity into flight, was also produced in Russia.

The rapid melting of the Arctic, predicted several years ago, has become a firm reality. In the summer of 2012, the area of ​​circumpolar ice set another anti-record, decreasing to 24% of the area of ​​the Arctic Ocean. As of September 16, it amounted to no more than 3.4 million square meters. km - by 760,000 sq. km less than the previous minimum. For the first time in recorded history, melting has spread across all of Greenland.

As the surface of the ice, which perfectly reflects solar radiation, shrinks, the Arctic darkens and absorbs more energy, warming up more and more. From a certain point, the melting process accelerates more and more and becomes irreversible. It seems that this moment is closer than anyone could have imagined: the ice may disappear altogether.

In our country, it is customary to have a positive attitude towards this: it is believed that the natural resources of the north will become accessible, constant sea navigation will open, and in general it will become warmer. Unfortunately, climate processes are so complex that such optimistic forecasts are unlikely to be reliable. For example, in September 2012,a study appeared showing that global warming is fraught with local cold snaps, and in our area it results in especially harsh and snowless winters.

The first results of the large-scale ENCODE project, which should become something like a beta version of Google Maps for the human genome, have been made available for free online access. The main object of interest is “junk” DNA.

In fact, the sequence of our DNA chain was revealed during the work on the Human Genome Project. It turned out that 95% of it is DNA, which does not encode genes at all and seems to be superfluous. However, the better we understand the work of chromosomes, the clearer it becomes what an important role the diverse regulatory mechanisms play in it, for which, in particular, this “junk” DNA is needed.

The ENCODE project is far from complete, as the purpose of each of the approximately three billion nitrogenous bases that make up human DNA remains to be determined. There is not much that is superfluous here: it has been shown that at least 80% of these bases exhibit constant biochemical activity.

In the “distant constellation” Tau Ceti, glorified by Vladimir Vysotsky, planets were discovered - five of them at once. In fact, Tau Ceti is one of the closest stars to us: it is only 11.9 light years away. The fourth planet is slightly closer to it than Venus is to the Sun, but Tau Ceti is almost twice as dim as the Sun, so the planet may well have liquid water.

A few months earlier, planets were found even closer - 4.3 light years from Earth, near the famous Alpha Centauri. This is a triple system, the second of whose stars has a hot twin of the Earth: with a slightly larger mass, the planet α Centauri Bb is heated above 1200 Celsius and, apparently, is completely covered with an ocean of molten lava.

However, the real hero of the search for distant planets has once again become the Kepler space telescope. Among his many discoveries in 2012 are the smallest planets known to date, including KOI-961.03, one-third the size of Earth—about the size of Mars. In November, the satellite's successful mission was extended for another four years.