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1.
Michael G. Burton 《Astronomy and Astrophysics Review》2010,18(4):417-469
Antarctica provides a unique environment for astronomers to practice their trade. The cold, dry and stable air found above
the high Antarctic plateau, as well as the pure ice below, offers new opportunities for the conduct of observational astronomy
across both the photon and the particle spectrum. The summits of the Antarctic plateau provide the best seeing conditions,
the darkest skies and the most transparent atmosphere of any earth-based observing site. Astronomical activities are now underway
at four plateau sites: the Amundsen-Scott South Pole Station, Concordia Station at Dome C, Kunlun Station at Dome A and Fuji
Station at Dome F, in addition to long duration ballooning from the coastal station of McMurdo, at stations run by the USA,
France/Italy, China, Japan and the USA, respectively. The astronomy conducted from Antarctica includes optical, infrared,
terahertz and sub-millimetre astronomy, measurements of cosmic microwave background anisotropies, solar astronomy, as well
as high energy astrophysics involving the measurement of cosmic rays, gamma rays and neutrinos. Antarctica is also the richest
source of meteorites on our planet. An extensive range of site testing measurements have been made over the high plateau sites.
In this article, we summarise the facets of Antarctica that are driving developments in astronomy there, and review the results
of the site testing experiments undertaken to quantify those characteristics of the Antarctic plateau relevant for astronomical
observation. We also outline the historical development of the astronomy on the continent, and then review the principal scientific
results to have emerged over the past three decades of activity in the discipline. These range from determination of the dominant
frequencies of the 5 min solar oscillation in 1979 to the highest angular scale measurements yet made of the power spectrum
of the CMBR anisotropies in 2010. They span through infrared views of the galactic ecology in star formation complexes in
1999, the first clear demonstration that the Universe was flat in 2000, the first detection of polarization in the CMBR in
2002, the mapping of the warm molecular gas across the ~ 300 pc extent of the Central Molecular Zone of our Galaxy in 2003,
the measurement of cosmic neutrinos in 2005, and imaging of the thermal Sunyaev Zel’dovich effect in galaxy clusters in 2008.
This review also discusses how science is conducted in Antarctica, and in particular the difficulties, as well as the advantages,
faced by astronomers seeking to bring their experiments there. It also reviews some of the political issues that will be encountered,
both at national and international level. Finally, the review discusses where Antarctic astronomy may be heading in the coming
decade, in particular plans for infrared and terahertz astronomy, including the new facilities being considered for these
wavebands at the high plateau stations. 相似文献
2.
J.S. Lawrence M.C.B. Ashley M.G. Burton J.W.V. Storey 《天文学报》2007,48(1):48-53
在南极洲高原的冰穹C有望发现非凡的天文观测条件,受此鼓舞,许多国际小组协同努力对该地的大气条件作全面的测量.评述对冰穹C的选址现况,讨论过去、现在和计划中的选址仪器,迄今已得到的结果,以及这些结果的天文含意. 相似文献
3.
《Chinese Astronomy and Astrophysics》2007,31(2):221-227
The expectation that exceptional conditions for astronomy would be found at Dome C on the high Antarctic plateau has motivated a coordinated effort by a number of international teams to comprehensively measure the atmospheric conditions at this site. This paper presents an overview of the current status of site testing at Dome C. We discuss the past, present, and planned instrumentation, the main results obtained to date, and the implications of these results. 相似文献
4.
Ji Yang Ying-Xi Zuo Zheng LOU Jing-Quan Cheng Qi-Zhou Zhang Sheng-Cai Shi Jia-Sheng Huang Qi-Jun Yao Zhong Wang 《天体物理学报》2013,(12):1493-1508
As the highest, coldest and driest place in Antarctica, Dome A provides exceptionally good observing conditions for ground-based observations over terahertz wavebands. The 5 m Dome A Terahertz Explorer (DATES) has been proposed to explore new terahertz windows, primarily over wavelengths between 350 and 200 pm. DATE5 will be an open-air, fully-steerable telescope that can function by unmanned operation with remote control. The telescope will be able to endure the harsh polar environment, including high altitude, very low temperature and very low air pressure. The unique specifications, including high accuracies for surface shape and pointing and fully automatic year-around remote operation, along with a stringent limit on the periods of on-site assembly, testing and maintenance, bring a number of challenges to the design, construction, assembly and operation of this telescope. This paper intro- duces general concepts related to the design of the DATE5 antenna. Beginning from an overview of the environmental and operational limitations, the design specifications and requirements of the DATE5 antenna are listed. From these, major aspects on the conceptual design studies, including the antenna optics, the backup structure, the pan- els, the subreflector, the mounting and the antenna base structure, are explained. Some critical issues of performance are justified through analyses that use computational fluid dynamics, thermal analysis and de-icing studies, and the proposed approaches for test operation and on-site assembly. Based on these studies, we conclude that the specifications of the DATE5 antenna can generally be met by using enhanced technological approaches. 相似文献
5.
Stefano Urbini Massimo Frezzotti Stefano Gandolfi Christian Vincent Claudio Scarchilli Luca Vittuari Michel Fily 《Global and Planetary Change》2008,60(3-4):576-588
Ice divide–dome behaviour is used for ice sheet mass balance studies and interpretation of ice core records. In order to characterize the historical behaviour (last 400 yr) of Dome C and Talos Dome (East Antarctica), ice velocities have been measured since 1996 using a GPS system, and the palaeo-spatial variability of snow accumulation has been surveyed using snow radar and firn cores. The snow accumulation distribution of both domes indicates distributions of accumulation that are non-symmetrical in relation to dome morphology. Changes in spatial distributions have been observed over the last few centuries, with a decrease in snow accumulation gradient along the wind direction at Talos Dome and a counter-clockwise rotation of accumulation distribution in the northern part of Dome C. Observations at Dome C reveal a significant increase in accumulation since the 1950s, which could correlate to altered snow accumulation patterns due to changes in snowfall trajectory. Snow accumulation mechanisms are different at the two domes: a wind-driven snow accumulation process operates at Talos Dome, whereas snowfall trajectory direction is the main factor at Dome C. Repeated GPS measurements made at Talos Dome have highlighted changes in ice velocity, with a deceleration in the NE portion, acceleration in the SW portion and migration of dome summit, which are apparently correlated with changes in accumulation distribution. The observed behaviour in accumulation and velocity indicates that even the most remote areas of East Antarctica have changed from a decadal to secular scale. 相似文献
6.
Xu Zhou Zhen-Yu Wu Zhao-Ji Jiang Xiang-Qun Cui Long-Long Feng Xue-Fei Gong Jing-Yao Hu Qi-Sheng Li Gen-Rong Liu Jun Ma Jia-Li Wang Li-Fan Wang Jiang-Hua Wu Li-Rong Xia Jun Yan Xiang-Yan Yuan Feng-Xiang Zhai Ru Zhang Zhen-Xi Zhu National Astronomical Observatories Chinese Academy of Sciences Beijing China Nanjing Institute of Astronomical Optics & Technology National Astronomical Observatories Nanjing China Purple Mo... 《中国天文和天体物理学报》2010,10(3)
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Abstract— Over 100 000 large interplanetary dust particles in the 50–500 μm size range have been recovered in clean conditions from ~600 tons of Antarctic melt ice water as both unmelted and partially melted/dehydrated micrometeorites and cosmic spherules. Flux measurements in both the Greenland and Antarctica ice sheets indicate that the micrometeorites deliver to the Earth's surface ~2000× more extraterrestrial material than brought by meteorites. Mineralogical and chemical studies of Antarctic micrometeorites indicate that they are only related to the relatively rare CM and CR carbonaceous chondrite groups, being mostly chondritic carbonaceous objects composed of highly unequilibrated assemblages of anhydrous and hydrous minerals. However, there are also marked differences between these two families of solar system objects, including higher C/O ratios and a very marked depletion of chondrules in micrometeorite matter; hence, they are “chondrites-without-chondrules.” Thus, the parent meteoroids of micrometeorites represent a dominant and new population of solar system objects, probably formed in the outer solar system and delivered to the inner solar system by the most appropriate vehicles, comets. One of the major purposes of this paper is to discuss applications of micrometeorite studies that have been previously presented to exobiologists but deal with the synthesis of prebiotic molecules on the early Earth, and more recently, with the early history of the solar system. 相似文献
9.
Lucia Sabbatini Francesco Cavaliere Giorgio Dall’Oglio Antonio Miriametro Licia Pizzo Dario Mancini Guido Torrioli 《Experimental Astronomy》2011,31(2-3):199-214
COCHISE (Cosmological Observations at Concordia with High-sensitivity Instrument for Source Extraction) is a 2.6 m telescope located on the high Antarctic Plateau near the Italian–French Concordia Base. The telescope is mainly devoted to Cosmological observations, able to operate between 200 μm and 3 mm of wavelength. In this paper we describe the main characteristics of the instrument. We also report on the first light, obtained during summer 2010–2011: this result marks the beginning of millimetre astrophysical observations at Concordia. Responsivity, noise equivalent temperature and field of view of the instrument are reported. At present COCHISE is the largest telescope located at Concordia. Beside the scientific expectations, the use of this kind of instrument in the Antarctic environment poses technological aspects of relevant interest: thus COCHISE can be considered as a pathfinder for future Antarctic telescopes. 相似文献
10.
P. B. Babadzhanov 《Astrophysics and Space Science》1986,118(1-2):95-97
The astronomical investigations in the present Tadjikistan (USSR) are carried out by the Institute of Astrophysics of the Academy of Sciences of Tadjik SSR. The main scientific fields of investigation are meteors, comets, and variable stars. The Institute has two observational stations: the Gissar observatory with photographic and radar meteor patrols, a 70 cm telescope, a 40 cm Zeiss astrograph, etc., and the Sanglok observatory with the Ritchey-Chrétien 1 m telescope.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
11.
The research activity in Japanese astronomy is described, taking into account the social and historical background. A trend in the last two decades is shown by the numbers of papers in 13 branches of astronomy. Major research facilities and international collaboration programs are summerized. Future programs under consideration are briefly discussed.Paper presented at the Lembang-Bamberg IAU Colloquium No. 80 on Double Stars: Physical Properties and Generic Relations, held at Bandung, Indonesia, 3–7 June, 1983. 相似文献
12.
We discuss some implications of iron whiskers condensing in supernova ejecta and being expelled into interstellar and intergalactic
space. The supposition that the universal microwave background is a relic from an early hot state of the Universe is shown
to be not as secure as is commonly supposed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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S. Hagelin E. Masciadri F. Lascaux J. Stoesz 《Monthly notices of the Royal Astronomical Society》2008,387(4):1499-1510
The atmospheric properties above three sites (Dome C, Dome A and the South Pole) on the Internal Antarctic Plateau are investigated for astronomical applications using the monthly median of the analyses from ECMWF (the European Centre for Medium-Range Weather Forecasts). Radiosoundings extended on a yearly time-scale at the South Pole and Dome C are used to quantify the reliability of the ECMWF analyses in the free atmosphere as well as in the boundary and surface layers, and to characterize the median wind speed in the first 100 m above the two sites. Thermodynamic instability properties in the free atmosphere above the three sites are quantified with monthly median values of the Richardson number. We find that the probability to trigger thermodynamic instabilities above 100 m is smaller on the Internal Antarctic Plateau than on mid-latitude sites. In spite of the generally more stable atmospheric conditions of the Antarctic sites compared to mid-latitude sites, Dome C shows worse thermodynamic instability conditions than those predicted above the South Pole and Dome A above 100 m. A rank of the Antarctic sites done with respect to the strength of the wind speed in the free atmosphere (ECMWF analyses) as well as the wind shear in the surface layer (radiosoundings) is presented. 相似文献
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Astronomical images currently provide large amounts of data. Lossy compression algorithms have recently been developed for high compression ratios. These compression technique introduce distortion in the compressed images and for high compression ratios, a blocking effect appears. We propose a modified compression algorithm based on the hcompress scheme, and we introduce a new decompression method based on the regularization theory The image is restored scale by scale in a multiresolution scheme and the information lost during the compression is recovered by applying a Tikhonov regularization constraint. The experimental results show that the blocking effect is reduced and some measurements made on a simulated image show that the astrometric and the photometric properties of the restored images are improved. 相似文献
17.
通过对古天文研究中用到的月亮历表的特点及制作方法的分析,认为Chapront的半分析月亮历表在大时间尺度下具有良好的稳定性,适合古天文研究的应用.在此理论基础上,制作了一个简化的、实用的月亮历表.该历表与Chapront的历表在1500B.C.~2000A.D.的黄经系统差在1.5″之内.为应用方便,给出了简化历表所用的月亮参数的高次表达式、傅里叶系数表及一个算例,读者可据此编制自己的计算月亮位置的程序。 相似文献
20.
At a time when major reforms are shaping the education system of the new South Africa, Astronomy could play a crucial role in the teaching and appreciation of science. There is as yet very little Astronomy in formal school curricula, so extra-mural approaches are necessary. In this regard, initiatives have been made by the astronomical national facilities, while many school pupils visit the two major planetariums. At an advanced level, various universities offer courses and professional training. 相似文献