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Digitization of Astronomical Photographic Plates of China and Astrometric Measurement of Single-exposure Plates
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作者 商正君 于涌 +9 位作者 王亮亮 杨美婷 杨静 沈世银 刘敏 徐权峰 崔辰州 樊东卫 唐正宏 赵建海 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第5期103-116,共14页
From the mid-19th century to the end of the 20th century, photographic plates served as the primary detectors for astronomical observations. Astronomical photographic observations in China began in 1901, and over a ce... From the mid-19th century to the end of the 20th century, photographic plates served as the primary detectors for astronomical observations. Astronomical photographic observations in China began in 1901, and over a century, a total of approximately 30,000 astronomical photographic plates were captured. These historical plates play an irreplaceable role in conducting long-term, time-domain astronomical research. To preserve and explore these valuable original astronomical observational data, Shanghai Astronomical Observatory has organized the transportation of plates, taken during nighttime observations from various stations across the country, to the Sheshan Plate Archive for centralized preservation. For the first time, plate information statistics were calculated. On this basis, the plates were cleaned and digitally scanned, and finally digitized images were acquired for 29,314 plates. In this study, using Gaia DR2 as the reference star catalog, astrometric processing was carried out successfully on 15,696 single-exposure plates, including object extraction, stellar identification,and plate model computation. As a result, for long focal length telescopes, such as the 40 cm double-tube refractor telescope, the 1.56 m reflector telescope at Shanghai Astronomical Observatory, and the 1m reflecting telescope at Yunnan Astronomical Observatory, the astrometric accuracy obtained for their plates is approximately 0."1–0."3. The distribution of astrometric accuracy for medium and short focal length telescopes ranges from 0."3 to 1."0. The relevant data of this batch of plates, including digitized images and a stellar catalog of the plates, are archived and released by the National Astronomical Data Center. Users can access and download plate data based on keywords such as station, telescope, observation year, and observed celestial coordinates. 展开更多
关键词 methods data analysis-techniques image processing-astronomical databases miscellaneous-astrometry
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:40
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi zheng-hong tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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The first data release(DR1) of the LAMOST regular survey 被引量:29
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作者 A-Li Luo Yong-Heng Zhao +142 位作者 Gang Zhao Li-Cai Deng Xiao-Wei Liu Yi-Peng Jing Gang Wang Hao-Tong Zhang Jian-Rong Shi Xiang-Qun Cui Yao-Quan Chu Guo-Ping Li Zhong-Rui Bai Yue Wu Yan Cai Shu-Yun Cao Zi-Huang Cao Jeffrey L.Carlin Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Li Chen Xue-Lei Chen Xiao-Yan Chen Ying Chen Norbert Christlieb Jia-Ru Chu Chen-Zhou Cui Yi-Qiao Dong Bing Du Dong-Wei Fan Lei Feng Jian-Ning Fu Peng Gao Xue-Fei Gong Bo-Zhong Gu Yan-Xin Guo Zhan-Wen Han Bo-Liang He Jin-Liang Hou Yong-Hui Hou Wen Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Zhi-Ying Huo Lei Jia Fang-Hua Jiang Xiang Jiang Zhi-Bo Jiang Ge Jin Xiao Kong Xu Kong Ya-Juan Lei Ai-Hua Li Chang-Hua Li Guang-Wei Li Hai-Ning Li Jian Li Qi Li Shuang Li Sha-Sha Li Xin-Nan Li Yan Li Yin-Bi Li Ye-Ping Li Yuan Liang Chien-Cheng Lin Chao Liu Gen-Rong Liu Guan-Qun Liu Zhi-Gang Liu Wen-Zhi Lu Yu Luo Yin-Dun Mao Heidi Newberg Ji-Jun Ni Zhao-Xiang Qi Yong-Jun Qi Shi-Yin Shen Huo-Ming Shi Jing Song Yi-Han Song Ding-Qiang Su Hong-Jun Su zheng-hong tang Qing-Sheng Tao Yuan Tian Dan Wang Da-Qi Wang Feng-Fei Wang Guo-Min Wang Hai Wang Hong-Chi Wang Jian Wang Jia-Ning Wang Jian-Ling Wang Jian-Ping Wang Jun-Xian Wang Lei Wang Meng-Xin Wang Shou-Guan Wang Shu-Qing Wang Xia Wang Ya-Nan Wang You Wang Yue-Fei Wang You-Fen Wang Peng Wei Ming-Zhi Wei Hong Wu Ke-Fei Wu Xue-Bing Wu Yu-Zhong Wu Xiao-Zheng Xing Ling-Zhe Xu Xin-Qi Xu Yan Xu Tai-Sheng Yan De-Hua Yang Hai-Feng Yang Hui-Qin Yang Ming Yang Zheng-Qiu Yao Yong Yu Hui Yuan Hai-Bo Yuan Hai-Long Yuan Wei-Min Yuan Chao Zhai En-Peng Zhang Hua-Wei Zhang Jian-Nan Zhang Li-Pin Zhang Wei Zhang Yong Zhang Yan-Xia Zhang Zheng-Chao Zhang Ming Zhao Fang Zhou Xu Zhou Jie Zhu Yong-Tian Zhu Si-Cheng Zou Fang Zuo 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第8期1095-1124,共30页
The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of ... The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of stars, galaxies and QSOs. Objects in both the pilot survey and the first year regular survey are included in the LAMOST DR1. The pilot survey started in October 2011 and ended in June 2012, and the data have been released to the public as the LAMOST Pilot Data Release in August 2012. The regular survey started in September 2012, and completed its first year of operation in June 2013. The LAMOST DR1 includes a total of 1202 plates containing 2 955 336 spectra, of which 1 790 879 spectra have observed signalto-noise ratio(SNR) ≥ 10. All data with SNR ≥ 2 are formally released as LAMOST DR1 under the LAMOST data policy. This data release contains a total of 2 204 696 spectra, of which 1 944 329 are stellar spectra, 12 082 are galaxy spectra and 5017 are quasars. The DR1 not only includes spectra, but also three stellar catalogs with measured parameters: late A,FGK-type stars with high quality spectra(1 061 918 entries), A-type stars(100 073 entries), and M-type stars(121 522 entries). This paper introduces the survey design, the observational and instrumental limitations, data reduction and analysis, and some caveats. A description of the FITS structure of spectral files and parameter catalogs is also provided. 展开更多
关键词 techniques: spectroscopic survey—data release—catalog
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Data release of the LAMOST pilot survey 被引量:8
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作者 A-Li Luo Hao-Tong Zhang +80 位作者 Yong-Heng Zhao Gang Zhao Xiang-Qun Cui Guo-Ping Li Yao-Quan Chu Jian-Rong Shi Gang Wang Jian-Nan Zhang Zhong-Rui Bai Xiao-Yan Chen Feng-Fei Wang Yan-Xin Guo Jian-Jun Chen Bing Du Xiao Kong Ya-Juan Lei Yin-Bi Li Yi-Han Song Yue Wu Yan-Xia Zhang Xin-Lin Zhou Fang Zuo Peng Du Lin He Wen Hou Yi-Qiao Dong Jian Li Guang-Wei Li Shuang Li Jing Song Yuan Tian Meng-Xin Wang Yong-Hui Hou Zhi-Ying Huo Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Qi Li Yin-Dun Mao zheng-hong tang Qing-Sheng Tao Liang-Ping Tu Da-Qing Wang Dan Wang Jian-Ping Wang Lei Wang Shou-Guan Wang Shu-Qing Wang Ya-Nan Wang You Wang Yue-Fei Wang Ming-Zhi Wei Xiang-Xiang Xue Xiao-Zheng Xing Ling-Zhe Xu Xin-Qi Xu Yan Xu De-Hua Yang Shi-Hai Yang Zheng-Qiu Yao Yong Yu Hui Yuan Chao Zhai En-Peng Zhang Jing Zhang Li-Ping Zhang WeiZhang Yong Zhang Zhen-Chao Zhang Ming Zhao Fang Zhou Yong-Tian Zhu Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1243-1246,共4页
This paper describes the data release of the LAMOST pilot survey, which includes data reduction, calibration, spectral analysis, data products and data access. The accuracy of the released data and the information abo... This paper describes the data release of the LAMOST pilot survey, which includes data reduction, calibration, spectral analysis, data products and data access. The accuracy of the released data and the information about the FITS headers of spectra are also introduced. The released data set includes 319 000 spectra and a catalog of these objects. 展开更多
关键词 techniques: spectroscopic survey data reduction data release
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Digitizer of astronomical plates at Shanghai Astronomical Observatory and its performance test 被引量:1
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作者 Yong Yu Jian-Hai Zhao +1 位作者 zheng-hong tang Zheng-Jun Shang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第3期67-76,共10页
Before CCD detectors were widely employed in observational astronomy, the main method of detection was the use of glass astrophotographic plates. Astronomical plates have been used to record information on the positio... Before CCD detectors were widely employed in observational astronomy, the main method of detection was the use of glass astrophotographic plates. Astronomical plates have been used to record information on the position and activity of celestial bodies for more than 100 years. There are about 30 000 astronomical plates in China, and the digitization of astronomical plates is of great significance for permanent preservation and to make full use of these valuable observation data. A digitizer with high precision and high measuring speed is a key piece of equipment for carrying out the task of dig- itizing these astronomical plates. A digitizer for glass astrophotographic plates was developed jointly by Shanghai Astronomical Observatory and Nishimura Co., Ltd of Japan. The digitizer's hardware was manufactured by Nishimura Co., Ltd, and the performance test, error corrections as well as image pro- cessing of the digitizer were carried out by Shanghai Astronomical Observatory. The main structure and working mode of the digitizer are introduced in this paper. A performance test shows that brightness uniformity of illumination within the measuring area is better than 0.15%, the repeatability of digitized positions is better than 0.2 μm and the repeatability of digitized brightness is better than 0.01 instrumen- tal magnitude. The systematic factors affecting digitized positions, such as lens distortion, the actual optical resolution, non-linearity of guide rails, non-uniformity of linear motors in the mobile platform, deviation of the image mosaic, and non-orthogonality between the direction of scanning and camera lin- ear array, are calibrated and evaluated. Based on an astronomical plate with a size of 300 mm × 300 mm, which was digitized at different angles, the conversion residuals of positions of common stars on dif- ferent images were investigated. The results show that the standard deviations of the residuals are better than 0.9μm and the residual distribution is almost random, which demonstrates the digitizer has a higher precision for digitization. 展开更多
关键词 astrometry - instrumentation detectors - methods data analysis - techniques IMAGEPROCESSING
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A model of geometric delay in Space VLBI 被引量:1
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作者 Shi-Long Liao zheng-hong tang Zhao-Xiang Qi 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第8期1029-1036,共8页
A model which includes the relativistic effect is derived that can be applied to space very long baseline interferometry (SVLBI) while taking observations of sources at infinite distance. In SVLBI, where one station... A model which includes the relativistic effect is derived that can be applied to space very long baseline interferometry (SVLBI) while taking observations of sources at infinite distance. In SVLBI, where one station is on a spacecraft, the length of the baseline and the orbiting station's maximum speed in an elliptical orbit around the Earth is much larger than the ground-based VLBI, which leads to a larger delay and higher delay rate. The delay models inside VLBI correlators are usually expressed as fifth-order polynomials during a limited time interval, which are evaluated by firmware in the correlator and track delays in the interferometer over the limited time interval. The higher SVLBI delay rate requires more accurate polynomial fitting and evaluation, as well as more frequent model updates. 展开更多
关键词 astrometry -- interferometric -- analytical
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The research objectives and observational possibilities for fast moving near-Earth asteroids
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作者 Anton Pomazan zheng-hong tang +3 位作者 Nadiia Maigurova Kai tang Yong Yu Yin-Dun Mao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第7期199-208,共10页
The paper describes observations of fast-moving near-Earth asteroids(NEAs) made with the small ground-based telescopes of National Time Service Center of Chinese Academy of Science(NTSC of CAS) and Research Institute ... The paper describes observations of fast-moving near-Earth asteroids(NEAs) made with the small ground-based telescopes of National Time Service Center of Chinese Academy of Science(NTSC of CAS) and Research Institute "Mykolaiv Astronomical Observatory"(RI MAO) by the rotating-drift-scan CCD(RDS CCD) technique. This technique is used to obtain the point images of both the studied objects and reference stars. The results of ongoing follow-up observations of NEAs are discussed. The residual differences(O-C) between the observed and calculated positions from JPL ephemeris were generally small for these asteroids. The standard deviations of these differences were typically ±(0.2′′-0.3′′) in both coordinates for objects with apparent velocity which substantially exceed FWHM for the given exposure time. The results of comparative statistics for such observations from the MPC database show that this is a good level of precision for NEAs. Moreover, the telescopes with the RDS CCD technique implemented can observe the NEAs that closely approach the Earth and with enough observations can improve the precision of determining their orbital elements and impact predictions. 展开更多
关键词 astronomical databases:miscellaneous surveys methods:observational techniques:miscellaneous ASTROMETRY minor planets asteroids:general
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12 GHz methanol maser outflow from the massive star-forming region: G35.20-0.74
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作者 Qing-Zeng Yan Bo Zhang +1 位作者 zheng-hong tang Xing-Wu Zheng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2013年第7期815-826,共12页
We report the internal proper motions of 12 GHz methanol masers in mas-sive star-forming region G35.20-0.74 observed with the Very Long Baseline Array (VLBA) at four epochs spanning about 1.5 yr. Two groups of maser... We report the internal proper motions of 12 GHz methanol masers in mas-sive star-forming region G35.20-0.74 observed with the Very Long Baseline Array (VLBA) at four epochs spanning about 1.5 yr. Two groups of maser features were de-tected, groups A and B, and the latter that had a V-shaped spatial distribution is likely tracing the north outflow in G35.20-0.74. We present a three-dimensional model for the kinematics of these masers, by assuming the interstellar medium was blown by the stellar wind from the driving source (G35.2N) of the outflow. Adopting a position angle of ~ 81° for the main axis of the outflow from previous studies, we estimate an inclination of 35 ° ± 5.5°, a velocity of 8.1 ± 0.7 km s^-1 for the stellar wind along the main axis and an expansion speed gradient of 0.05 ± 0.016 km s^-1 AU^-1. From the model, we derive the age of the north outflow in G35.20-0.74 to be ~ 1.6 × 10^4 yr. 展开更多
关键词 masers - ISM: molecules - stars: kinematics - stars: individual(G35.20-0.74) - stars: winds OUTFLOWS
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A new telescope with three fields of view to measure the orientation parameters of the Moon and terrestrial planets
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作者 Li-Zao Sun Cheng-Li Huang +5 位作者 Yong Yu Zhao-Xiang Qi zheng-hong tang Ming Zhao De-Hua Yang Tong Wu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第2期121-132,共12页
For lots of scientific questions about lunar physics deep inside the Moon,in-situ observation on lunar physical libration is one of the most potential ways.In this paper,we propose a brand new optical telescope functi... For lots of scientific questions about lunar physics deep inside the Moon,in-situ observation on lunar physical libration is one of the most potential ways.In this paper,we propose a brand new optical telescope functioned with simultaneously observing multiple(here there are three)fields of view(FOVs)for in-situ observation of lunar physical libration.The telescope can be placed at any place with any attitude on the Moon and do not require manned install,control or operation.It passively,continuously and simultaneously observe stars in three FOVs along with rotation of the Moon.Libration is to be measured and studied from celestial motion of the directions of three FOVs from image processing.The concept and design of this telescope are firstly introduced in this paper.The principle and feasibility of the method of insitu observation are also demonstrated.From simulation,precision of the determined lunar physical libration is expected to be several milliarcsecs,about two orders of magnitude better than the current precision of libration by lunar laser ranging observation.Libration data with milliarcsec precision level can play a valuable role in the study of the physics and dynamics of the interior of the Moon.This telescope can also be applied to observe the rotation of other terrestrial planets like Mars. 展开更多
关键词 astrometry-telescopes-methods observational-reference systems
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Differential measurement of atmospheric refraction using a telescope with double fields of view
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作者 Yong Yu Jian-Jun Cao +2 位作者 zheng-hong tang Hao Luo Ming Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第10期1742-1750,共9页
For the sake of advancing theoretical research about atmospheric refrac- tion, the atmospheric refraction observed at lower angles of elevation is still worth analyzing and exploring. In some engineering applications,... For the sake of advancing theoretical research about atmospheric refrac- tion, the atmospheric refraction observed at lower angles of elevation is still worth analyzing and exploring. In some engineering applications, objects with a larger zenith distance must sometimes be observed. Carrying out observational research on atmospheric refraction at lower angles of elevation has an important significance. However, it has been considered difficult to measure the atmospheric refraction at lower angles of elevation. A new idea for determining atmospheric refraction by utilizing differential measurement with double fields of view is proposed. Taking the observational principle used by the HIPPARCOS satellite as a reference, a prototype with double fields of view was developed. In August 201 3, experimental observations were carried out and atmospheric refractions at lower angles of elevation were obtained by the prototype. The measured value of atmospheric refraction at a zenith distance of 78.8° was 240.23″±0.27″, and the feasibility of differential measurement of atmospheric refraction with double fields of view was verified. Limitations of the prototype, such as inadequate ability to gather light, lack of accurate meteorological data recording, and a low level of automation in observation and data processing, are pointed out, which need to be improved in subsequent work. 展开更多
关键词 astrometry -- atmospheric effects -- methods: observational
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A long time span relativistic precession model of the Earth
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作者 Kai tang Michael H.Soffel +2 位作者 Jin-He Tao Wen-Biao Han zheng-hong tang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第4期583-596,共14页
A numerical solution to the Earth's precession in a relativistic framework for a long time span is presented here. We obtain the motion of the solar system in the Barycentric Celestial Reference System by numerical i... A numerical solution to the Earth's precession in a relativistic framework for a long time span is presented here. We obtain the motion of the solar system in the Barycentric Celestial Reference System by numerical integration with a symplectic in- tegrator. Special Newtonian corrections accounting for tidal dissipation are included in the force model. The part representing Earth's rotation is calculated in the Geocentric Celestial Reference System by integrating the post-Newtonian equations of motion published by Klioner et al. All the main relativistic effects are included following Klioner et al. In particular, we consider several relativistic reference systems with cor- responding time scales, scaled constants and parameters. Approximate expressions for Earth's precession in the interval ~1 Myr around J2000.0 are provided. In the interval 4-2000 years around J2000.0, the difference compared to the P03 precession theory is only several arcseconds and the results are consistent with other long-term precession theories. 展开更多
关键词 astrometry -- ephemeris -- post-Newtonian
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Astrometry of three near Earth asteroids with the Lijiang 2.4 m telescope
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作者 Xi-Liang Zhang Yong Yu +4 位作者 Xue-Li Wang Chuan-Jun Wang Liang Chang Yu-Feng Fan zheng-hong tang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第3期435-442,共8页
Under the framework of observational campaigns organized by the GAIA Follow Up Network for Solar System Objects, three near Earth asteroids, 367943 Duende, 99942 Apophis and 2013 TV135, were observed with the Lijiang ... Under the framework of observational campaigns organized by the GAIA Follow Up Network for Solar System Objects, three near Earth asteroids, 367943 Duende, 99942 Apophis and 2013 TV135, were observed with the Lijiang 2.4m telescope administered by Yunnan Observatories. The software package PRISM was used to calibrate the CCD fields and measure the positions of 99942 Apophis and 2013 TV135, and our own software was used for 367943 Duende. A comparison of the results show that the ephemerides of INPOP10a and JPL are consistent for 99942 Apophis and 2013 TV135, however, they are quite inconsistent for 367943 Duende. Moreover, we have found that differences between the mean values in the ephemerides of INPOP10a and JPL are about 72" and -199" in right ascension and declination respectively for 367943 Duende. Moreover, the ephemeris published by JPL is reliable in terms of the mean observed-minus-calculated (O - C) residuals in right ascension and declination of about 2.72" and 1.49" respectively. 展开更多
关键词 astrometry -- near Earth objects -- astrometric observation --ephemerides
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