It's just a giant ball of hydrogen and helium gas.

它只是一个巨大的氢气和氦气的球。

The airship is filled with helium gas and does not have a crew.

飞艇里充满氦气，没有船员。

But first, the students need to fill the ballon with helium gas, so it can rise.

但首先，学生们需要将气球装满氦气，这样气球才能升空。

Let's make the helium gas a, and chlorine will be our gas b.

让我们将氦气设为 a，将氯气设为我们的气体 b。

So what happens next happens fast:  They shoot the muons into a tube containing helium gas.

所以接下来发生的事情发生得很快：他们将 μ 子发射到装有氦气的管子中。

We could talk about the pressure from the helium gas in the balloon, or the stress from the helium gas in the balloon.

我们可以谈论气球中氦气的压力，或气球中氦气的压力。

Jupiter is made of mostly hydrogen and helium gas, so trying to land on it would be like trying to land on a cloud here on Earth.

木星几乎由氢气和氦气构成，因此尝试在上面降落可能就像尝试降落在地球的云层上一样。

In the early 1920s, she used the latest learnings about quantum physics to come up with the idea that stars are all made mainly of hydrogen and helium gas.

在 20 世纪 20 年代初，她利用关于量子物理学的最新知识，提出了恒星主要由氢气和氦气组成的观点。

As time went on, the hydrogen and helium gas in the galaxies would break up into smaller clouds that would collapse under their own gravity.

随着时间的推移，星系中的氢气和氦气会分裂成更小的云，这些云会在自身引力的作用下坍塌。