{"title":"2016-2021年利用盖亚DR3对六颗木卫二不规则卫星进行新的天体测量定位","authors":"","doi":"10.1016/j.icarus.2024.116352","DOIUrl":null,"url":null,"abstract":"<div><div>The Jovian system is like a miniature solar system, with the system being more than twice as massive as all the other planets combined and having many natural satellites. Its formation and early evolution had a profound influence on our knowledge of the sculpting of the architecture of the solar system. Astrometric observations are of importance, based on these observations, its orbital dynamics, as well as its origin sometimes, of a solar system object can be determined. We aimed to obtain good astrometric positions of some irregular satellites Elara, Pasiphae, Sinope, Lysithea, Carme and Ananke to refine their orbits and ephemerides, and to understand their dynamics. We have taken, processed and reduced 964 ground-based CCD frames obtained between 2016 and 2021 by the 2.4 m telescope at the Lijiang Station of Yunnan Observatory over 27 nights. Among CCD image processing, the image subtraction technique of ISIS is employed to eliminate star images that are close to or/and almost overlapped with those of our targets in 2019. The star catalog Gaia DR3 is utilized for astrometric calibration, in which a weight scheme is applied to solve more accurate plate model. For all targets, their theoretical positions are retrieved from the Institut de Mécanique Céleste et de Calcul des Éphémérides (IMCCE) ephemeris. Our results show the mean (O - C)s (observed minus computed) of the positional residuals of all targets are <span><math><mrow><mo>−</mo><msup><mrow><mn>0</mn></mrow><mrow><mo>′</mo><mo>′</mo></mrow></msup><mo>.</mo><mn>007</mn></mrow></math></span> and <span><math><mrow><msup><mrow><mn>0</mn></mrow><mrow><mo>′</mo><mo>′</mo></mrow></msup><mo>.</mo><mn>011</mn></mrow></math></span> in R.A. and Dec., respectively. Their corresponding standard deviations are about <span><math><mrow><msup><mrow><mn>0</mn></mrow><mrow><mo>′</mo><mo>′</mo></mrow></msup><mo>.</mo><mn>05</mn></mrow></math></span> in each direction, except for Ananke (the faintest satellite) with its standard deviation about <span><math><mrow><msup><mrow><mn>0</mn></mrow><mrow><mo>′</mo><mo>′</mo></mrow></msup><mo>.</mo><mn>08</mn></mrow></math></span> in each direction.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":null,"pages":null},"PeriodicalIF":2.5000,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"New astrometric positions for six Jovian irregular satellites using Gaia DR3 in 2016 — 2021\",\"authors\":\"\",\"doi\":\"10.1016/j.icarus.2024.116352\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>The Jovian system is like a miniature solar system, with the system being more than twice as massive as all the other planets combined and having many natural satellites. Its formation and early evolution had a profound influence on our knowledge of the sculpting of the architecture of the solar system. Astrometric observations are of importance, based on these observations, its orbital dynamics, as well as its origin sometimes, of a solar system object can be determined. We aimed to obtain good astrometric positions of some irregular satellites Elara, Pasiphae, Sinope, Lysithea, Carme and Ananke to refine their orbits and ephemerides, and to understand their dynamics. We have taken, processed and reduced 964 ground-based CCD frames obtained between 2016 and 2021 by the 2.4 m telescope at the Lijiang Station of Yunnan Observatory over 27 nights. Among CCD image processing, the image subtraction technique of ISIS is employed to eliminate star images that are close to or/and almost overlapped with those of our targets in 2019. The star catalog Gaia DR3 is utilized for astrometric calibration, in which a weight scheme is applied to solve more accurate plate model. For all targets, their theoretical positions are retrieved from the Institut de Mécanique Céleste et de Calcul des Éphémérides (IMCCE) ephemeris. Our results show the mean (O - C)s (observed minus computed) of the positional residuals of all targets are <span><math><mrow><mo>−</mo><msup><mrow><mn>0</mn></mrow><mrow><mo>′</mo><mo>′</mo></mrow></msup><mo>.</mo><mn>007</mn></mrow></math></span> and <span><math><mrow><msup><mrow><mn>0</mn></mrow><mrow><mo>′</mo><mo>′</mo></mrow></msup><mo>.</mo><mn>011</mn></mrow></math></span> in R.A. and Dec., respectively. Their corresponding standard deviations are about <span><math><mrow><msup><mrow><mn>0</mn></mrow><mrow><mo>′</mo><mo>′</mo></mrow></msup><mo>.</mo><mn>05</mn></mrow></math></span> in each direction, except for Ananke (the faintest satellite) with its standard deviation about <span><math><mrow><msup><mrow><mn>0</mn></mrow><mrow><mo>′</mo><mo>′</mo></mrow></msup><mo>.</mo><mn>08</mn></mrow></math></span> in each direction.</div></div>\",\"PeriodicalId\":13199,\"journal\":{\"name\":\"Icarus\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":2.5000,\"publicationDate\":\"2024-10-24\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Icarus\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0019103524004123\",\"RegionNum\":2,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"ASTRONOMY & ASTROPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Icarus","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0019103524004123","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
New astrometric positions for six Jovian irregular satellites using Gaia DR3 in 2016 — 2021
The Jovian system is like a miniature solar system, with the system being more than twice as massive as all the other planets combined and having many natural satellites. Its formation and early evolution had a profound influence on our knowledge of the sculpting of the architecture of the solar system. Astrometric observations are of importance, based on these observations, its orbital dynamics, as well as its origin sometimes, of a solar system object can be determined. We aimed to obtain good astrometric positions of some irregular satellites Elara, Pasiphae, Sinope, Lysithea, Carme and Ananke to refine their orbits and ephemerides, and to understand their dynamics. We have taken, processed and reduced 964 ground-based CCD frames obtained between 2016 and 2021 by the 2.4 m telescope at the Lijiang Station of Yunnan Observatory over 27 nights. Among CCD image processing, the image subtraction technique of ISIS is employed to eliminate star images that are close to or/and almost overlapped with those of our targets in 2019. The star catalog Gaia DR3 is utilized for astrometric calibration, in which a weight scheme is applied to solve more accurate plate model. For all targets, their theoretical positions are retrieved from the Institut de Mécanique Céleste et de Calcul des Éphémérides (IMCCE) ephemeris. Our results show the mean (O - C)s (observed minus computed) of the positional residuals of all targets are and in R.A. and Dec., respectively. Their corresponding standard deviations are about in each direction, except for Ananke (the faintest satellite) with its standard deviation about in each direction.
期刊介绍:
Icarus is devoted to the publication of original contributions in the field of Solar System studies. Manuscripts reporting the results of new research - observational, experimental, or theoretical - concerning the astronomy, geology, meteorology, physics, chemistry, biology, and other scientific aspects of our Solar System or extrasolar systems are welcome. The journal generally does not publish papers devoted exclusively to the Sun, the Earth, celestial mechanics, meteoritics, or astrophysics. Icarus does not publish papers that provide "improved" versions of Bode''s law, or other numerical relations, without a sound physical basis. Icarus does not publish meeting announcements or general notices. Reviews, historical papers, and manuscripts describing spacecraft instrumentation may be considered, but only with prior approval of the editor. An entire issue of the journal is occasionally devoted to a single subject, usually arising from a conference on the same topic. The language of publication is English. American or British usage is accepted, but not a mixture of these.