Search Publications
Tianyu-Search for the Second Solar System and Explore the Dynamic Univers
Shi, X.; Yang, M.; Lin, J. +32 more
Giant planets like Jupiter and Saturn, play important roles in the formation and habitability of Earth-like planets. The detection of solar system analogs that have multiple cold giant planets is essential for our understanding of planet habitability and planet formation. Although transit surveys such as Kepler and Transiting Exoplanet Survey Sate…
Large-scale CO Multi-line Observations of the S187 HII Region
Chen, X. P.; Sun, Y.; Xu, X. Y. +1 more
The strong feedback of massive stars profoundly affects the interstellar medium around them, and may trigger the formation of next-generation stars. S187 is a massive star formation region located in the second quadrant of the Milky Way, showing a ``Collect and Collapse" triggered star formation pattern. Based on the $^{12}\mathrm{CO}$/$^{13}\math…
Multi-star System Observations Based on the Direct-imaging Method
Zhao, G.; Chen, Y. L.; Zhu, Y. T. +1 more
The direct-imaging exploration can obtain comprehensive physical information of exoplanets, which is a key technology to search for extraterrestrial life in the future. In this paper, based on our recent high-contrast imaging data of ground-based telescope, the newly discovered multi-star candidates are presented. In the early stage, combined with…
Overall Properties of the ICRF and Gaia-CRF
Liu, N.
The International Celestial Reference System (ICRS) now has realizations at several frequencies, all with an accuracy of several tens of mircoarcsecond (µas) level, including the International Celestial Reference Frame (ICRF) based on observations of the very long baseline interferometry (VLBI) at S/X, K, and X/Ka band, and the Gaia celestia…
Experimental CCD Positional Observations of the Five Major Uranian Satellites
Wang, N.; Peng, Q. Y.; Xie, H. J. +1 more
Two hundred and forty-eight CCD frames, observed by using 1 m telescope at Yunnan Observatories for four consecutive nights, have been reduced to derive the precise positions of the five Uranian major satellites (Ariel, Umbriel, Titania, Oberon, and Miranda). The positions of satellites are measured with respect to the stars in Gaia DR1 (Data Rele…
DBSCAN Clustering Algorithm for Detection of Nearby Open Clusters Based on Gaia-DR2
Wang, C.; Xu, S. K.; Zhuang, L. H. +1 more
In this paper, we attempt to use the DBSCAN (Density-Based Spatial Clustering of Applications with Noise) clustering algorithm to detect nearby open clusters based on Gaia Data Release 2 (Gaia-DR2). We select 594284 stars (within a distance of 100 pc to the sun) from the Gaia-DR2 catalog, and construct a five dimensional phase space (three dimensi…
Exoplanet Detection by Astrometric Method
Xu, W. W.; Liao, X. H.; Zhou, Y. H. +1 more
As we known, the exoplanets are mostly detected by the methods of radial velocity and transit, only one is found by the astrometric method. As the data of the gaia to be released, astrometry will become one of the most important method for detecting exoplanets gradually. Based on the position sequence of stars, this paper discusses the calculation…
Analogue Simulation and Orbital Solving Algorithm of Astrometric Exoplanet Detection
Ji, J. H.; Huang, P. H.
Astrometry is an effective method to detect exoplanets. It has many advantages that other detection methods do not bear, such as providing three dimensional planetary orbit and determining the planetary mass. Astrometry will enrich the sample of exoplanets. As the high-precision astrometric satellite Gaia (Global Astrometry interferometer for Astr…