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We describe the public ESO near-IR variability survey (VVV) scanning the Milky Way bulge and an adjacent section of the mid-plane where star formation activity is high. The survey will take 1929 h of observations with the 4-m VISTA telescope during 5 years (2010–2014), covering ~109 point sources across an area of 520 deg2, including 33 known globular clusters and ~350 open clusters. The final product will be a deep near-IR atlas in five passbands (0.9–2.5 μm) and a catalogue of more than 106 variable point sources. Unlike single-epoch surveys that, in most cases, only produce 2-D maps, the VVV variable star survey will enable the construction of a 3-D map of the surveyed region using well-understood distance indicators such as RR Lyrae stars, and Cepheids. It will yield important information on the ages of the populations. The observations will be combined with data from MACHO, OGLE, EROS, VST, Spitzer, HST, Chandra, INTEGRAL, WISE, Fermi LAT, XMM-Newton, GAIA and ALMA for a complete understanding of the variable sources in the inner Milky Way. This public survey will provide data available to the whole community and therefore will enable further studies of the history of the Milky Way, its globular cluster evolution, and the population census of the Galactic Bulge and center, as well as the investigations of the star forming regions in the disk. The combined variable star catalogues will have important implications for theoretical investigations of pulsation properties of stars.  相似文献   
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The Cha I dark cloud is a nearby (140 pc) site of low-mass star formation. Due to its high galactic latitude (b=–16°) it is an observationally favourable object for study at radio as well as other wavelengths. We have mapped the central part of the cloud in the C18O (1–0) line using both the 1.2-m Columbia Southern Millimeter-Wave Telescope at Cerro Tololo and the 15-m Swedish-ESO Submillimetre Telescope (SEST).Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain.  相似文献   
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During the past decade we have compiled a large molecular line data base of massive star forming regions in the southern Milky Way. These regions are confined into giant molecular clouds that trace the galactic spiral arms. Their radial distribution has a pronounced peak midway between the Sun and the galactic center, which in the IV quadrant corresponds to the location of the Norma Spiral arm. We study in some detail one of the foremost regions of massive star formation in the Norma arm, using millimeter continuum and line emission maps obtained with the SEST, APEX, and ASTE telescopes. It is a multiple system evolving along a complete GMC core, candidate for future ALMA observations.  相似文献   
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Some laws governing the self-purification of marine waters from oil products have been considered using the Sea of Azov and the NW shelf of the Black Sea as models. A number of principally important features of this process have been established including marked spatial heterogenity, and capacity for a sharp decline in the efficiency of destruction during anthropogenic transformations of marine ecosystems, etc. On the basis of a special mathematical model and numerous experiments, an estimation in the first approximation was made of the efficiency of the self-purification of the areas investigated and their characteristic regions. The value obtained is significantly smaller than the actual amount of oil products entering the sea as runoff. A number of recommendations have been made on the use of self-purification values for establishing standards for discharges of waste waters.  相似文献   
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Natural Hazards - Understanding the culture of preparedness is essential to improve public policies and programs aimed to promote population preparedness to cope with natural hazards. The present...  相似文献   
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