土星E環是土星環最外圍、密度低、但卻分佈很廣的塵埃環。根據地表可見光的觀測，不同於其他行星環的成冪尺寸分佈( power law size distribution )，E環塵埃主要由半徑約一微米( μm )的塵埃所組成，其密度最高處與土星一小衛星Enceladus軌道相近。E環特殊的塵埃顆粒尺寸及空間分佈( size & radial distribution )、環物質與土星磁球層( magnetosphere )間的交互作用，皆是目前與土星相關的有趣課題。
不同於土星主環( Saturn Main Ring )，E環的塵埃密度低，塵埃粒子之間不易發生碰撞作用；因此E環塵埃粒子的運動便可反映出其受到的不同擾動。1992年，M. Horanyi藉由計算E環塵埃粒子的運動方程式，提出的理論認為：位於土星磁球層中的衛星Enceladus受到撞擊，自Enceladus拋出的塵埃粒子與磁球層電漿粒子(電子、離子)碰撞而帶電後，受到土星赤道突起的重力擾動、羅倫茲力( Lorentz force )、與太陽光輻射壓力( radiation pressure )，使特定大小塵埃粒子(半徑約一微米( μm )的離心率增加，亦即由原本的圓軌道成為橢圓軌道，而因此從該衛星的軌道擴展至觀測到的E環範圍。
而D. Hamilton與J. Burns於1994年科學( Science )期刊發表的文章則認為自Enceladus拋出的E環的塵埃粒子，數年內會再和土星磁球層中的衛星碰撞，產生下一代的環物質，而形成自我維持( self-sustained )的機制。
然而，隨著由美國航空暨太空總署( NASA )與歐洲太空局( ESA )合作的卡西尼-惠更斯太空船進入土星系統，其上搭載的塵埃偵測儀器( Cosmic Dust Analyzer，宇宙塵埃分析儀)直接測量E環塵埃的初步結果，E環物質分佈位置比預期的更廣(包括垂直與水平方向)，而其尺寸分佈更與之前認為的一微米不同、為二項分佈( binomial distribution )。
我所進行的工作，除了考慮已知的效應外，更加入一可能、但尚未證實的大尺度跨磁尾電場( large scale cross-tail electric field )，嘗試去解釋先前模型無法解釋的觀測現象，並且對於E環塵埃-土星衛星/土星主環間碰撞情形、E環塵埃和土星磁球層間的交互作用有進一步的了解和理論計算。

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