Oort cloud
01
奥尔特云, 奥尔特星云
a distant, hypothetical region surrounding the solar system, thought to harbor icy bodies and comets
例子
The Oort Cloud is considered a source of long-period comets that occasionally enter the inner solar system.
奥尔特云被认为是偶尔进入内太阳系的长周期彗星的来源。
