Above them are red supergiants, massive stars beginning their death stage.

在它们上面是红超巨星，即开启死亡阶段的巨大的恒星。

For example, Betelgeuse in Orion is a red supergiant, and one of the brightest stars in the sky despite being over 600 light years away.

例如，猎户座中的参宿四是一颗红色的超巨星，尽管它距离我们超过了600光年，但仍然是天空中最亮的恒星之一。

It swells up just as the Sun will, but instead of becoming a red giant, it generates so much energy it becomes a red supergiant.

它会像太阳一样膨胀，但它没有变成红巨星，而是产生了大量的能量，变成了超大星。