A concept of a space hazard counteraction system: Astronomical aspects

The basic science of astronomy and, primarily, its branch responsible for studying the Solar System, face the most important practical task posed by nature and the development of human civilization—to study space hazards and to seek methods of counteracting them. In pursuance of the joint Resolution of the Federal Space Agency (Roscosmos) and the RAS (Russian Academy of Sciences) Space Council of June 23, 2010, the RAS Institute of Astronomy in collaboration with other scientific and industrial organizations prepared a draft concept of the federal-level program targeted at creating a system of space hazard detection and counteraction. The main ideas and astronomical content of the concept are considered in this article.     

Dynamics and Origin of Comets: New Problems Appeared after the <Emphasis Type="Italic">Rosetta</Emphasis> Space Mission

The data obtained in the recent Rosetta space mission to comet 67P/Churyumov–Gerasimenko have had a profound impact on the understanding of the nature of comets. In addition to revising the notions on the physical properties and structure of comets, this addresses dynamical aspects of the formation of the observed cometary populations (short- and long-period comets, Centaurs, trans-Neptunian objects, and Oort-cloud objects). In the review, we discuss new problems that have appeared in the theory of dynamical evolution and origin of comets due to the Rosetta mission.     

Structure and Dynamics of the Centaur Population: Constraints on the Origin of Short-Period Comets

The origin of Jupiter-family comets is linked to the intermediate stage of evolution through the Centaur region. Thus the structure of the Centaur population provides important constraints on sources of short-period comets. We show that our model of the Oort cloud evolution gives results which are consistent with the orbital distribution of observed Centaurs. In particular, it explains the existence of the large population of Centaurs with semimajor axes greater than 60 AU. The main source for these objects is the inner Oort cloud. Both Jupiter-family and Halley-type comets are produced by Centaurs originating from the Oort cloud. The injection rate for Jupiter-family comets coming from the inner Oort cloud is, at least, not less than that for a model based on the observed sample of high-eccentricity trans-Neptunian objects.     

Fractionation of Colloidal Matter of Stratal Waters during Deep Burial of Radioactive Wastes

The paper presents ultrafiltration and microscopic study of colloidal matter from radioactive waste disposal site at the Siberian Chemical Plant. It is established that most part of actinides (55–90%) are mainly bonded to colloidal particles, whereas only 20% natural uranium are bonded to >5–µm particles at the background site. In general, the retention of transuranium elements (TUE) from contaminated waters by membranes with pore size from 200 to 5 nm increases with increase of anthropogenic uranium content in water     

Distribution of the near-earth objects

This paper analyzes the distribution of the orbits of near-Earth minor bodies from the data on more than 7500 objects. The distribution of large near-Earth objects (NEOs) with absolute magnitudes of H < 18 is generally consistent with the earlier predictions (Bottke et al., 2002; Stuart, 2003), although we have revealed a previously undetected maximum in the distribution of perihelion distances q near q = 0.5 AU. The study of the orbital distribution for the entire sample of all detected objects has found new significant features. In particular, the distribution of perihelion longitudes seriously deviates from a homogeneous pattern; its variations are roughly 40% of its mean value. These deviations cannot be stochastic, which is confirmed by the Kolmogorov-Smirnov test with a more than 0.9999 probability. These features can be explained by the dynamic behavior of the minor bodies related to secular resonances with Jupiter. For the objects with H < 18, the variations in the perihelion longitude distribution are not so apparent. By extrapolating the orbital characteristics of the NEOs with H < 18, we have obtained longitudinal, latitudinal, and radial distributions of potentially hazardous objects in a heliocentric ecliptic coordinate frame. The differences in the orbital distributions of objects of different size appear not to be a consequence of observational selection, but could indicate different sources of the NEOs.     

Ephemerides of Asteroid Satellites and Estimation of Their Accuracy

Solar System Research - The article presents new results on motion modeling and creation of ephemeris of satellites of asteroids based on observations. In previous work on the project, ephemeris of...     

The key features of the bottom sediment composition in the anoxic Lake Mogil’noe

In the summer 2006, integrated geological, geochemical, hydrological, and hydrochemical studies were performed on the relict anoxic Lake Mogil’noe (down to 16 m depths) located on Kil’din Island in the Barents Sea. The chemical and grain-size composition of the bottom sediments were compared for the lake (a permanently anoxic basin) and the Baltic Sea Deeps (periodically anoxic basins). The vertical location of the hydrogen sulfide layer boundary in the lake (9–11 m depths) was practically the same from 1974 up to now. The concentrations of suspended particulate matter in the lake in June and July 2006 appeared to be close to its summer concentrations in the seawaters of the open part of the Baltic Sea. The mud from Lake Mogil’noe compared to those of the Baltic Sea Deeps are characterized by fluid and flake consistency and by pronounced admixtures of sandy and silty fractions probably of eolic origin. The lacustrine mud contain much plant remains; iron sulfides and vivanite were also found in ooze. The concentrations of 22 elements determined in the lacustrine bottom sediments were of the same levels as those found here 33 years ago. The concentrations also appeared to be close to those in the corresponding grain-size types of the bottom sediments in the Baltic Sea. The low C_org/N value (5% on average) in the mud of Mogil’noe Lake compared to the values for the mud of the Baltic Sea Deeps (10% on average) points to the considerable planktogenic component in the organic matter composition of the lacustrine mud. No indications were reveled for anthropogenic contaminations of the lacustrine bottom sediments with toxic metals.     

A risky business: Mining, rent and the neoliberalization of “risk”

Natural resource investment in the mining sector is often mediated through conflicts over rent distribution between corporate capital and landowner states. Recent rounds of neoliberal policy promoted by the World Bank have highlighted the need for landowner states to offer incentives in order to attract “high risk” capital investment. In Sub-Saharan Africa, in particular, countries have been pushed to offer attractive fiscal terms to capital, thereby lowering the proportion traditionally called rent. This paper examines how the concept of “risk” has been mobilized to legitimate such skewed distributional arrangements. While certain conceptions of social and ecological “risk” have been prevalent in political and social theoretic discourse on mining, such focus elides the overwhelming contemporary power of our notion of “neoliberal risk” – or the financial/market risks – in actually setting the distributional terms of mineral investment. We illustrate our argument by examining the nexus of World Bank mining policy promotion and Tanzanian policy in the late 1990s meant to attract foreign direct investment in gold production. In closing, we suggest that just as “risk” is used to legitimate attractive fiscal terms for investment, recent events highlight how skewed distribution of benefits may set into motion risks that corporate capital had not bargained for.     

Geological structure of the Kashevarov Trough (central Sea of Okhotsk)

This paper reports the composition and age of rocks dredged from the Kashevarov Trough (central Sea of Okhotsk) during cruise 41 of the R/V Akademik M.A. Lavrentyev in 2006. It was found that the Late Cretaceous and Eocene volcanics from the Kashevarov Trough and Okhotsk-Chukotka volcanic belt, structures of which are traceable in the Sea of Okhotsk, have similar petrographic and geochemical features. The Cenozoic sedimentary cover consists of three different-age complexes: (1) the late Oligocene (∼28.2–24.0 Ma); (2) the terminal late Oligocene-early Miocene (24.0–20.3 Ma); (3) the terminal late Pliocene-early Pleistocene (2.0–1.0 Ma). The upper Oligocene-lower Miocene sediments were deposited in relatively shallow-water settings, whereas the late Pliocene-early Pleistocene complex was formed in deeper environments, which was probably determined by tectonic processes. The geological data indicate that the Kashevarov Trough and the surrounding underwater rises represented in the Oligocene-early Miocene a single shelf zone of the Sea of Okhotsk, which is underlain by a structurally integral Mesozoic basement and is now subsided to depths of 800–1000 m.     

Measuring the processes and outcomes of post-disaster housing recovery: lessons from Gölcük, Turkey

Despite a growing literature on post-disaster recovery, our understanding of how housing recovery is measured remains limited. This paper is a step in filling the gap in the literature by presenting an overview of how recovery organizations measured post-disaster permanent housing recovery in Gölcük, Turkey, following the August 17, 1999 earthquake. Based on in-depth interviews, focus groups, participant observation, and review of secondary sources, the paper highlights the limitations of measuring housing recovery as the number of permanent housing units built in a timely manner. It suggests that recovery organizations need to measure post-disaster housing recovery by developing context-specific, process- and outcome-oriented measures. In the case of Gölcük, process-oriented measures could have been related to the land appropriation, public participation processes, and inter-organizational collaboration while outcome-oriented measures could have been related to the level of satisfaction with homes built and equity among the housing beneficiaries.