文章基本信息

标题：The 2016 Reactivations of the Main-belt Comets 238P/Read and 288P/(300163) 2006 VW 139
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作者：Henry H. Hsieh ; Masateru Ishiguro ; Yoonyoung Kim 等
期刊名称：The Astronomical journal
印刷版ISSN：0004-6256
电子版ISSN：1538-3881
出版年度：2018
卷号：156
期号：5
页码：1-18
DOI：10.3847/1538-3881/aae528
语种：English
出版社：American Institute of Physics
摘要：We report observations of the reactivations of the main-belt comets (MBCs) 238P/Read and 288P/(300163) 2006 VW 139 that also track the evolution of each object’s activity over several months in 2016 and 2017. We additionally identify and analyze archival SDSS data showing 288P to have been active in 2000, meaning that both 238P and 288P have now each been confirmed to be active near perihelion on three separate occasions. From data obtained of 288P from 2012–2015 when it appeared inactive, we find best-fit R-band H, G phase function parameters of H R =16.80±0.12 mag and G R =0.18±0.11, corresponding to effective component radii of r c =0.80±0.04 km, assuming a binary system with equally sized components. Fitting linear functions to ejected dust masses inferred for 238P and 288P soon after their observed reactivations in 2016, we find an initial average net dust production rate of = ˙ M 0.7 0.3 d kgs −1 and a best-fit start date of 2016 March 11 (when the object was at a true anomaly of ν=−63°) for 238P, and an initial average net dust production rate of =  ˙ M 5.6 0.7 d kgs −1 and a best-fit start date of 2016 August 5 (when the object was at ν=−27°) for 288P. Applying similar analyses to archival data, we find similar start points for previous active episodes for both objects, suggesting that minimal mantle growth or ice recession occurred between the active episodes in question. Some changes in dust production rates between active episodes are detected, however. More detailed dust modeling is suggested to further clarify the process of activity evolution in MBCs.
关键词：comets: general;comets: individual (238P, 288P);minor planets, asteroids: general