提示：点击例句中的单词，就可以看到词义解释

Previous observations had traced only incoming helium atoms .

以前的观测只追踪了氦原子。

Single-ion helium occurs when one electron is lost .

氦离子是氦原子失去一个电子形成的。

Stars like our sun fuse hydrogen in their cores into helium .

太阳一类的恒星在其核心将氢融合成氦。

Note that hydrogen and helium are the major constituents of jupiter 's atmosphere .

需要注意的是木星有大气层，其主要成分是氢和氦。

A crane carrying the capsule follows the helium balloon during the launch on sunday .

星期天，在准备起飞期间一个起重机正吊着一个带有氦气球的气压舱。