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Seven new radar brightness and altitude images are presented. They are each of a small circular region within the equatorial belt of Venus. Resolution is, typically, 10 by 10 km; altitude contour spacing is 500 m. In addition, an image of the large rough feature β is presented with 25 by 25 km resolution. 相似文献
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A number of coastal and ocean observation systems exist throughout the Gulf of Mexico (GOM), but the network of systems is not currently linked or integrated and at present not fully implemented. The network of local systems are diverse, typically involving unique mandates and several different funding sources at various levels of permanence. The purpose of this paper is to describe the ocean observation systems that currently exist in the GOM, and to identify and quantify the expected economic benefits that may result from the implementation of an integrated regional network. Improved ocean observation systems are expected to reduce the uncertainty of ocean/weather forecasting and to enhance the value of ocean/weather information throughout the Gulf region. The source of benefits and the size of activity from which improved ocean observation benefits may be derived are estimated for private sector, non-market, and public sector activities categorized according to marine transportation, commercial fishing, recreational fishing, search and rescue operations, and pollution management. The benefits of improved ocean observation systems to energy exploration, development, and production activities are estimated, and a discussion of potential benefits to lightering activities, environmental monitoring, royalty payments, and engineering design are highlighted. 相似文献
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T. Murphy T. Mauch A. Green R. W. Hunstead B. Piestrzynska A. P. Kels P. Sztajer 《Monthly notices of the Royal Astronomical Society》2007,382(1):382-392
We present the first data release from the second epoch Molonglo Galactic Plane Survey (MGPS-2). MGPS-2 was carried out with the Molonglo Observatory Synthesis Telescope at a frequency of 843 MHz and with a restoring beam of 45 × 45 arcsec2 , making it the highest resolution large-scale radio survey of the southern Galactic plane. It covers the range | b | < 10° and 245° < l < 365° , and is the Galactic counterpart to the Sydney University Molonglo Sky Survey (SUMSS) which covers the whole southern sky with δ≤−30° (| b | > 10° ).
In this paper, we present the MGPS-2 compact source catalogue. The catalogue has 48 850 sources above a limiting peak brightness of 10 mJy beam−1 . Positions in the catalogue are accurate to 1–2 arcsec. A full catalogue including extended sources is in preparation. We have carried out an analysis of the compact source density across the Galactic plane and find that the source density is not statistically higher than the density expected from the extragalactic source density alone.
We also present version 2.0 of the SUMSS image data and catalogue which is now available online. The data consist of 629 4.3°× 4.3° mosaic images covering the 8100 deg2 of sky with δ≤−30° and | b | > 10° . The catalogue contains 210 412 radio sources to a limiting peak brightness of 6 mJy beam−1 at δ≤−50° and 10 mJy beam−1 at δ > −50° . We describe the updates and improvements made to the SUMSS cataloguing process. 相似文献
In this paper, we present the MGPS-2 compact source catalogue. The catalogue has 48 850 sources above a limiting peak brightness of 10 mJy beam
We also present version 2.0 of the SUMSS image data and catalogue which is now available online. The data consist of 629 4.3°× 4.3° mosaic images covering the 8100 deg
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