Asteroid mass determination at Nikolaev Observatory

Masses of asteroids are topical for research in ephemerides computations and density evaluations. Details of the dynamical method are given for asteroid mass determinations. Preliminary masses of 13 asteroids, obtained with relative errors less than 50%, are presented from non-weighted least squares. Accuracy improvement of mass values for dynamical computations is evident using contemporary observations of 1999-2006. Statistics of the fitting ephemerides to the observations is also discussed.     

On the radiative and thermodynamic properties of the cosmic radiations using COBE FIRAS instrument data: II. Extragalactic far infrared background radiation

Using formula to describe the average spectrum of the extragalactic far infrared background (FIRB) radiation measured by the COBE FIRAS instrument in the 0.15–2.4 THz frequency interval at mean temperature T=18.5 K, the radiative and thermodynamic properties, such as the total emissivity, total radiation power per unit area, total energy density, number density of photons, Helmholtz free energy density, entropy density, heat capacity at constant volume, and pressure are calculated. The value for the total intensity received in the 0.15–2.4 THz frequency interval is equal to 13.6 nW?m^?2?sr^?1. This value is about 19.4 % of the total intensity expected from the energy released by stellar nucleosynthesis over cosmic history. The radiative and thermodynamic functions of the extragalactic far infrared background (FIRB) radiation are calculated at redshift z=1.5.     

Remote mountain lakes of Eastern Siberia: a pattern of ecologically pure non-industrialised water-bodies

A 3-year study of the biota of the remote mountain lakes of Amut, Balan-Tamur, and Yakondykon, situated in the Dzherginsky State Reserve in the Baikalian region of Eastern Siberia, was carried out from 2006 to 2008. Examining the biota of non-modern and non-industrialised mountain lakes allowed us to reveal its background in relation to the species composition of plankton, the main groups of benthos and fishes, production potential, and seasonal dynamics of the ecosystem’s basic links. Our data on pH and biota were compared with the findings of a previous study in 1986 in order to evaluate possible changes associated with probable acidification. We observed that the lakes of the Dzherginsky State Reserve have high species diversity. Despite this, they are classed as oligotrophic water-bodies with regard to the development level of their planktonic and benthic coenoses. These lakes are not polluted by anthropogenic activity and so could be considered as a pattern of ecologically pure water-bodies. It is important to add that high mountain lakes of Pribaikalye presently serve as refuges for species that were widespread during past geological epochs.