Global heliospheric termination shock strength in the solar–interstellar interaction

IF 14.3 1区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

Nature Astronomy Pub Date : 2025-08-19 DOI:10.1038/s41550-025-02634-3

E. J. Zirnstein, R. Kumar, B. L. Shrestha, P. Swaczyna, M. A. Dayeh, J. Heerikhuisen, J. R. Szalay

{"title":"Global heliospheric termination shock strength in the solar–interstellar interaction","authors":"E. J. Zirnstein, R. Kumar, B. L. Shrestha, P. Swaczyna, M. A. Dayeh, J. Heerikhuisen, J. R. Szalay","doi":"10.1038/s41550-025-02634-3","DOIUrl":null,"url":null,"abstract":"<p>A heliospheric termination shock (HTS) surrounds our Solar System at approximately 100 astronomical units from the Sun, where the expanding solar wind (SW) is compressed and heated before encountering the interstellar medium. HTS-accelerated particles govern the pressure balance with the interstellar medium, but little is known about the global properties of the HTS beyond in situ measurements from Voyager in only two directions of the sky. Here we fill this gap by extracting the HTS strength using particle-in-cell, test particle and magnetohydrodynamic simulations, constrained by Interstellar Boundary Explorer observations of energetic neutral atoms produced from HTS-accelerated particles. Our results reveal there is a higher compression near the poles during solar minimum compared with solar maximum due to the higher Mach number flow. North–south asymmetries arise from the disparate evolution of the polar coronal holes, while minimum compression near the flanks is probably due to SW slowing from mass loading over a greater distance to the HTS. The results imply a strong connection between the HTS strength and the SW and interstellar medium dynamics.</p>","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"7 1","pages":""},"PeriodicalIF":14.3000,"publicationDate":"2025-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nature Astronomy","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1038/s41550-025-02634-3","RegionNum":1,"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

A heliospheric termination shock (HTS) surrounds our Solar System at approximately 100 astronomical units from the Sun, where the expanding solar wind (SW) is compressed and heated before encountering the interstellar medium. HTS-accelerated particles govern the pressure balance with the interstellar medium, but little is known about the global properties of the HTS beyond in situ measurements from Voyager in only two directions of the sky. Here we fill this gap by extracting the HTS strength using particle-in-cell, test particle and magnetohydrodynamic simulations, constrained by Interstellar Boundary Explorer observations of energetic neutral atoms produced from HTS-accelerated particles. Our results reveal there is a higher compression near the poles during solar minimum compared with solar maximum due to the higher Mach number flow. North–south asymmetries arise from the disparate evolution of the polar coronal holes, while minimum compression near the flanks is probably due to SW slowing from mass loading over a greater distance to the HTS. The results imply a strong connection between the HTS strength and the SW and interstellar medium dynamics.

Abstract Image

查看原文本刊更多论文

太阳-星际相互作用中的全球日球端激波强度

一个日球端激波（HTS）围绕着我们的太阳系，距离太阳大约100个天文单位，在那里膨胀的太阳风（SW）在遇到星际介质之前被压缩和加热。高温超导加速粒子控制着与星际介质的压力平衡，但除了旅行者号在天空两个方向的原位测量之外，对高温超导的整体特性知之甚少。在这里，我们填补了这一空白，通过使用细胞内粒子、测试粒子和磁流体动力学模拟来提取高温超导强度，并受到星际边界探测器对高温超导加速粒子产生的高能中性原子的观测的限制。结果表明，在太阳极小期，由于马赫数流较大，在极附近的压缩比太阳极大期大。南北不对称源于两极日冕洞的不同演化，而侧翼附近的最小压缩可能是由于距离高温超导较远的质量负载导致的西南偏南减速。结果表明，高温超导强度与SW和星际介质动力学之间有很强的联系。

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

Nature Astronomy Physics and Astronomy-Astronomy and Astrophysics

CiteScore

19.50

自引率

2.80%

发文量

252

期刊介绍： Nature Astronomy, the oldest science, has played a significant role in the history of Nature. Throughout the years, pioneering discoveries such as the first quasar, exoplanet, and understanding of spiral nebulae have been reported in the journal. With the introduction of Nature Astronomy, the field now receives expanded coverage, welcoming research in astronomy, astrophysics, and planetary science. The primary objective is to encourage closer collaboration among researchers in these related areas. Similar to other journals under the Nature brand, Nature Astronomy boasts a devoted team of professional editors, ensuring fairness and rigorous peer-review processes. The journal maintains high standards in copy-editing and production, ensuring timely publication and editorial independence. In addition to original research, Nature Astronomy publishes a wide range of content, including Comments, Reviews, News and Views, Features, and Correspondence. This diverse collection covers various disciplines within astronomy and includes contributions from a diverse range of voices.