New evidence supporting past dust ejections from active asteroid (4015) Wilson–Harrington

IF 5.4 2区 物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS
Sunho Jin, Masateru Ishiguro, Jooyeon Geem, Hiroyuki Naito, Jun Takahashi, Hiroshi Akitaya, Daisuke Kuroda, Seitaro Urakawa, Seiko Takagi, Tatsuharu Oono, Tomohiko Sekiguchi, Davide Perna, Simone Ieva, Yoonsoo P. Bach, Ryo Imazawa, Koji S. Kawabata, Makoto Watanabe, Hangbin Jo
{"title":"New evidence supporting past dust ejections from active asteroid (4015) Wilson–Harrington","authors":"Sunho Jin, Masateru Ishiguro, Jooyeon Geem, Hiroyuki Naito, Jun Takahashi, Hiroshi Akitaya, Daisuke Kuroda, Seitaro Urakawa, Seiko Takagi, Tatsuharu Oono, Tomohiko Sekiguchi, Davide Perna, Simone Ieva, Yoonsoo P. Bach, Ryo Imazawa, Koji S. Kawabata, Makoto Watanabe, Hangbin Jo","doi":"10.1051/0004-6361/202451225","DOIUrl":null,"url":null,"abstract":"<i>Context.<i/> (4015) Wilson-Harrington (hereafter, WH) was discovered as a comet in 1949 but has a dynamical property consistent with that of a near-Earth asteroid. Although there is a report that the 1949 activity is associated with an ion tail, the cause of the activity has not yet been identified.<i>Aims.<i/> This work aims to reveal the mysterious comet-like activity of the near-Earth asteroid.<i>Methods.<i/> We conducted new polarimetric observations of WH from May 2022 to January 2023, reanalyses of the photographic plate images taken at the time of its discovery in 1949, and dust tail simulation modelings, where the dust terminal velocity and ejection epoch are taken into account.<i>Results.<i/> We found that this object shows polarization characteristics similar to those of low-albedo asteroids. We derived the geometric albedo ranging from <i>p<sub>V<sub/><i/> = 0.076 ± 0.010 to <i>p<sub>V<sub/><i/> = 0.094 ± 0.018 from our polarimetry (the values vary depending on the data used for fitting and the slope-albedo relationship coefficients). In addition, the 1949 image showed an increase in brightness around the nucleus. Furthermore, we found that the color of the tail is consistent with sunlight, suggesting that the 1949 activity is associated with dust ejection. From the dust tail analysis, ~9 × 10<sup>5<sup/> kg of material was ejected episodically at a low velocity equivalent to or even slower than the escape velocity.<i>Conclusions.<i/> We conclude that WH is most likely an active asteroid of main belt origin and that the activity in 1949 was likely triggered by mass shedding due to fast rotation.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":5.4000,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Astronomy & Astrophysics","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1051/0004-6361/202451225","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
引用次数: 0

Abstract

Context. (4015) Wilson-Harrington (hereafter, WH) was discovered as a comet in 1949 but has a dynamical property consistent with that of a near-Earth asteroid. Although there is a report that the 1949 activity is associated with an ion tail, the cause of the activity has not yet been identified.Aims. This work aims to reveal the mysterious comet-like activity of the near-Earth asteroid.Methods. We conducted new polarimetric observations of WH from May 2022 to January 2023, reanalyses of the photographic plate images taken at the time of its discovery in 1949, and dust tail simulation modelings, where the dust terminal velocity and ejection epoch are taken into account.Results. We found that this object shows polarization characteristics similar to those of low-albedo asteroids. We derived the geometric albedo ranging from pV = 0.076 ± 0.010 to pV = 0.094 ± 0.018 from our polarimetry (the values vary depending on the data used for fitting and the slope-albedo relationship coefficients). In addition, the 1949 image showed an increase in brightness around the nucleus. Furthermore, we found that the color of the tail is consistent with sunlight, suggesting that the 1949 activity is associated with dust ejection. From the dust tail analysis, ~9 × 105 kg of material was ejected episodically at a low velocity equivalent to or even slower than the escape velocity.Conclusions. We conclude that WH is most likely an active asteroid of main belt origin and that the activity in 1949 was likely triggered by mass shedding due to fast rotation.
支持活动小行星(4015)威尔逊-哈灵顿过去尘埃喷射的新证据
背景(4015) 威尔逊-哈灵顿(Wilson-Harrington,以下简称 "WH")于 1949 年作为彗星被发现,但其动力学特性与近地小行星一致。虽然有报告称 1949 年的活动与离子尾有关,但活动的原因尚未查明。这项工作旨在揭示近地小行星类似彗星的神秘活动。我们在2022年5月至2023年1月期间对WH进行了新的极化观测,重新分析了1949年发现WH时拍摄的照片板图像,并建立了尘埃尾模拟模型,其中考虑了尘埃末端速度和抛射纪元。我们发现该天体显示出与低反照率小行星类似的偏振特性。我们通过偏振测量得出的几何反照率从 pV = 0.076 ± 0.010 到 pV = 0.094 ± 0.018 不等(数值因拟合数据和斜率-反照率关系系数而异)。此外,1949 年的图像显示核周围亮度增加。此外,我们还发现尾部的颜色与太阳光一致,这表明 1949 年的活动与尘埃喷射有关。通过对尘埃尾部的分析,约有 9 × 105 千克的物质以相当于甚至慢于逃逸速度的低速被喷射出来。我们的结论是,WH 很可能是一颗起源于主带的活动小行星,1949 年的活动很可能是由快速旋转导致的质量脱落引发的。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Astronomy & Astrophysics
Astronomy & Astrophysics 地学天文-天文与天体物理
CiteScore
10.20
自引率
27.70%
发文量
2105
审稿时长
1-2 weeks
期刊介绍: Astronomy & Astrophysics is an international Journal that publishes papers on all aspects of astronomy and astrophysics (theoretical, observational, and instrumental) independently of the techniques used to obtain the results.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信