Ашық рұқсат
Рұқсат берілді
Рұқсат ақылы немесе тек жазылушылар үшін
№ 1 (2021)
Editorial
Priroda. 2021;(1):2-3
2-3
THE SEARCH FOR LIFE ON MARS CONTINUES
Priroda. 2021;(1):4-4
4-4
General Strategy for the Search for Life on Mars and an Expedition to the Crater Jezero
Аннотация
Main features of the Noachain, Hesperian, and Amazonian periods are considered as influence factors on potential contamination/origin, protection, and evolution of microorganisms. Mars evolution during Noachian likely resembled the early evolution of Earth. This potential similarity allows origin of life on Mars. Relatively short Hesperian period was marked by intensive volcanism, fluvial and glacial activity; however environmental conditions on its surface largely overstepped the survival limits and microorganisms were either conserved in permafrost or migrated to deeper water-rich horizons. In Amazonian, Mars represented a frozen desert with very harsh conditions on the surface that was constantly sterilized by the cosmic radiation. The generally unfavorable conditions for the life evolution suggest that primitive organisms, which potentially could be formed on early Mars, were unable to evolve up to complex, multicellular organisms. Ecological niches of modern Mars are considered. Among them, the deep subsurface water horizons and сryopegs have the highest potential for survivability of microorganisms as conditions in these environments are independent from the condition on the surface. Geology of the ancient crater lake Jezero, which is the primary target of the NASA mission Perseverance, are briefly considered. Clay minerals and carbonates within the crater could represent a potential reservoir where possible remnants of microorganisms could be accumulated and stored.
Priroda. 2021;(1):5-18
5-18
Are We Martians?
Аннотация
The article discusses the assumption that life first originated on Mars and then was delivered by Martian meteorites on Earth. Typical collection sites for meteorites, including Martian ones, and photographs of some of them are presented. The 287 known to date Martian meteorites vary in mass from 11 g to 18 kg. Isotope studies have shown that the largest of them, before entering the Earth’s atmosphere, had a mass of 150 to 270 kg and were in outer space from 1.2 to 10.8 Myr. However, the calculations show that the range of values for the time spent by a Martian meteorite in space is very large; almost direct Mars—Earth flights with a space flight duration of about several years are possible with a probability of 10–7. This very low probability, however, could be realized. During the period of intense meteorite bombardment 3.9–4.5 billion years ago, when its rates were 3–4 orders of magnitude higher than in the modern era, such express—flights could and even should have happened.
Priroda. 2021;(1):19-23
19-23
Microtomography of Fossil Bryozoans
Аннотация
Bryozoans are colonial animals with a complex skeleton. The methods that are usually used to study the internal structure of fossil colonies of bryozoans are often destructive, laborious, and provide little information. This essay presents the results of the study of Paleozoic and Mesozoic bryozoans using X-ray computed microtomography. We believe that in future this method will become increasingly important for the study of fossils.
Priroda. 2021;(1):24-33
24-33
Nature Conservation in the Republic of Tatarstan
Аннотация
Tatarstan Republic is located in the east of the Russian Plain, at the confluence of the two largest European rivers — the Volga and the Kama. Intense anthropogenic impact on nature began here in the early Middle Ages. Today the Republic is one of the most economically developed regions of the Russian Federation. To date, a big network of specially protected natural areas is highly developed in the Tatarstan Republic. It includes the UNESCO Biosphere Reserve, federal (nature reserves and national parks), regional (nature refuges and natural monuments) and local nature protected arrears, created to preserve the diversity of natural communities, flora, fauna, and the very beauty nature places of Tatarstan.
Priroda. 2021;(1):34-44
34-44
Fortov’s Maximum. To the 75th Anniversary of the Big Man Who Died
Аннотация
Владимира Евгеньевича Фортова не стало 29 ноября 2020 года. 23 января ему исполнилось бы 75 лет. Эти годы вместили многое: работу в исследовательских лабораториях и в министерских кабинетах, руководство Российским фондом фундаментальных исследований в первые годы его существования и Российской академией наук в очень трудное для нее время, расследование причин и последствий аварий Чернобыльской АЭС и Саяно-Шушенской ГЭС, путешествие под парусом через Атлантику, участие в экспедициях на Северный и Южный полюсы, погружение в аппарате «Мир» на дно Байкала и восхождение на гималайскую вершину. И конечно, дело всей его жизни — физику экстремальных состояний вещества. Он принадлежал к той научной школе, где не знали слова «невозможно». Невозможно поверить, что его не стало…
Priroda. 2021;(1):45-75
45-75
Unexpected discovery of hematite on the Moon. Etruscan shrew shrinks its brain for winter.
Priroda. 2021;(1):76-78
76-78
N.Yu.Klyuge. SISTEMATIKA NASEKOMYKh I PRINTsIPY KLADOENDEZISA: v 2-kh t.
Priroda. 2021;(1):79-79
79-79