Dust is nowhere near as hot as a star, therefore optical telescopes cannot observe it.

尘埃温度远不及恒星，所以光学望远镜难以观测到。

youdao

We cannot observe the objective world in our subjective states of consciousness.

我们无法在我们的主观的意识状态中观察客观的世界。

youdao

The problem is that we cannot observe what a climate without the presence of human activity looks like, since we can only observe the current state of the climate.

然而问题是，我们无法实际观察不受人类活动影响的气候会是如何，因为我们只能观察目前的气候状况。

youdao

And this is important because it means that since we cannot observe, we cannot talk about individual electrons.

这很重要,因为这意味着我们不能观察，不能谈及单个电子。

麻省理工公开课 - 固态化学导论课程节选