Glossary term: 行星环
Description: 太阳系中的四颗巨行星（木星、土星、天王星和海王星）都被无数小冰块或岩石所环绕，这些微小物质的尺寸从微米到数米不等，形成了巨大的行星环结构。目前，我们还无法确定系外行星是否有类似的环系统。最壮观的行星环是围绕土星的复杂环系统，由多个环组成，并被环缝分隔开。其中一些结构是由与土星较大的卫星相互作用而形成的，而环内轨道运行的小卫星则清理出了环缝。关于这些行星环的形成有多种假说，大多数认为是由于卫星在土星引力作用下被撕裂或剥离而形成。据估计，土星的行星环将在几亿年内逐渐消失——从天文学的标准来看，这并不是很长的时间。木星、天王星和海王星的环系统相对不那么明显。
Related Terms:
See this term in other languages
Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher The translation of this term and its definition is still awaiting approval
The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".
If you notice a factual or translation error in this glossary term or definition then please get in touch.
Related Media
土星
Credit: 美国国家航空航天局、欧空局、A. Simon（戈达德太空飞行中心）和 M.H. Wong（加州大学伯克利分校） credit link
License: CC-BY-4.0 Creative Commons 署名 4.0 国际 (CC BY 4.0) icons
天王星与星环
Credit: 美国国家航空航天局、欧洲航天局和 M. Showalter（SETI 研究所） credit link
License: PD Public Domain icons
