defoamer chemical,defoamer antifoam,defoaming agent,foam and antifoam NINGBO LUCKY CHEMICAL INDUSTRY CO. LTD , https://www.nbluckychem.com
Progress in the accurate interpretation of the molecular line of the comet water from the Purple Mountain Observatory
[ Instrument Network Instrument Development ] On September 30th, the Monthly Notices of the Royal Astronomical Society and Astronomy and Astrophysics published the online research of Ji Jinshan, a researcher at the Purple Mountain Observatory of the Chinese Academy of Sciences. The Huixue team and the German Marp Institute of Solar System researcher Paul Hartogh and other groups based on the Rosetta 67UR/CG (sub) millimeter wave observation data obtained by the Rosetta detector MIRO instrument, the first to establish and use the three-dimensional model for the comet burst The molecular line observation data is analyzed, and the model is combined with MIRO instrument parameters to analyze the three-dimensional spatial effects of remote sensing observation. Relevant research has scientific significance for revealing the characteristics and evolution history of comet burst activity.
The ESA Rosetta Comet Detector arrived at the Jupiter Comet 67P/CG in 2014. During the orbit, it obtained a large amount of high-precision observation data, helping humans to record the possible origin and evolution of the solar system. The small celestial body of information has a deeper understanding and understanding. The core scientific target of the millimeter-wave detector MIRO equipped on Rosetta is to detect the main gas composition and abundance of the comet burst, the isotope ratio and the temperature of the surface of the nucleus and subsurface. In the two-year observation, MIRO obtained a large amount of data with extremely rich information. However, the traditional research work is based on the one-dimensional spherical symmetry model, ignoring the extremely irregular shape of 67P/CG, solar illumination and nucleus surface. Factors such as the distribution of activity, which cannot meet the need to interpret high-precision MIRO observation data. Therefore, how to take these factors into account and establish a more reasonable 3D model to better analyze and understand MIRO observation data, and obtain more valuable information becomes a difficult problem.
In order to accurately interpret MIRO observation data, Zhao Yuhui, an associate researcher from the Purple Mountain Observatory, and Ladislav Rezac, Ph.D., from the Max Planck Institute of Solar Research, have established a set of fusion three-dimensional shape models, illumination models, gas volatilization models, three-dimensional burst models, and three-dimensional The three-dimensional "data analysis" tools of radiation transfer model and observation simulation and spectral line simulation are applied to the research of MIRO early water molecule observation data and the analysis of three-dimensional effects of remote sensing instrument observation data.
The model is the only three-dimensional radiation transfer model considering the complex shape, rotation state and illumination of the nucleus. The traditional one-dimensional model can significantly improve the high-precision observation data of the molecular line of the millimeter and sub-millimeter bands. The result of the fitting, in order to more deeply and accurately interpret the burst characteristics contained in the observation data. The model will be used to analyze more MIRO observation data and to interpret the high-precision comet observation data obtained by ground observation equipment such as ALMA and JCMT, and obtain the molecular composition and abundance of ice-like small celestial bodies in different ethnic groups of the solar system. More and more accurate information, but also provide an important scientific basis for the task of the main comet detection and the long-period comet detection in the pre-research stage in China's future small celestial exploration mission.
The first authors of the two work were Zhao Yuhui and Ladislav Rezac. Collaborators include Paul Hartogh, Ji Jianghui, Dr. Raphael Marschall of the Southwest Research Institute, and Uwe Keller of Dr. Brunswick University. The research work was supported by the National Natural Science Foundation of China and Germany (11761131008), the National Natural Science Foundation of China (11673072, 11633009, 11661161013, 11473073), the Innovation Crossing Team of the Chinese Academy of Sciences, and the Key Laboratory of Planetary Sciences of the Chinese Academy of Sciences.
The contribution of different regions of the 67P/CG surface to the MIRO observation data (the ratio of the color representation to the contribution maximum) and the projection of the MIRO field of view on the surface of the nucleus (white circle) (top left: the surface illumination distribution of the nucleus, The upper right, lower left and lower right respectively indicate that the detector is 2.5km, 5km and 20km away from the surface of the helium nucleus, indicating that the remote sensing observation data is mostly from the contribution of the "whole" surface and cannot be compared with the instrument field of view on the surface of the helium nucleus. The physical properties and activity are simply related (Rezac et al., 2019).
67P/CG complex shape and distribution of surface temperature (left) and water molecule production rate (right) caused by illumination (Zhao et al., 2019).