这样说来，我们猜测这可新发现的行星主要由氢气和氦气组成。
Having said that, we suspect that this new planet is made mostly of hydrogen and helium gas.
氦气比空气轻得多并且是惰性气体，这意味着，当它与空气和明火接触不会燃烧，而氢气却会(请看下图)。
Helium is far lighter than air and is inert, which means it won't combust when you combine it with air and energy, like Hydrogen does (below).
这有时被称为“追溯”。例如，大爆炸理论对原始时期氢气，氦气和氘的大量存在做出了非常精确的预测。
This is sometimes called "retrodiction. " For example, the Big Bang theory makes very precise predictions about the primordial abundances of hydrogen, helium, and deuterium.
应用推荐