... A non-linear relationship is observed between the sky brightness on clear and overcast nights, with a change in behavior near the rural to urban landuse transition. ... The great variation in skyglow radiance observed from site-to-site and with changing meteorological conditions underlines the need for a long-term international monitoring program. he introduction of artificial light has caused an unprecedented disruption to the nighttime environment over large areas of the Earth. ... Data processing...

ISSN 1063-7737, Astronomy Letters, 2011, Vol. ... 2011. ... 37, No. 9, pp. 643­650. i Lenticular Galaxies with Ultraviolet Rings M. A. Ilyina* and O. K. Sil'chenko Received April 28, 2011 ** Sternberg Astronomical Institute, Universitetskii pr. ... We have analyzed the optical structure of these galaxies using SDSS (Sloan Digital Sky Survey) surface photometry, measured the colors of the rings, and compared the radial localizations of the ring structures in the optical and ultraviolet spectral ranges. ...

... 000, 1­12 (2009) Printed 11 February 2010 A (MN L TEX style file v2.2) Analytical approximations of K -corrections in optical and near-infrared bands I1gor V. Chilingarian1 2 ,2,3 , Anne-Laure Melchior 1,4 and Ivan Yu. ... Received 2010 February 01; in original form 2009 August 14 ABSTRACT To compare photometric properties of galaxies at different redshifts, the fluxes need to be corrected for the changes of effective rest-frame wavelengths of filter bandpasses, called K -corrections. ... Table 1. ...