What dark energy is, though, is a mystery.

然而暗能量是什么，仍然是个谜。

youdao

Of course, we don't understand that picture—we don't know what dark energy is, and we don't know what dark matter is.

当然，我们并不了解这幅图像——我们不知道什么是暗能量，也不知道暗物质是什么。

youdao

Yet, in the nearly 40 years that followed, researchers still haven't been able to figure out what dark matter is made of.

然而，在后来的近40年里，研究人员仍然每能弄清暗物质的组成。

youdao

Scientists can observe what they believe to be dark matter only through its gravity.

VOA: special.2009.07.21

So, that's what is meant by the term, Dark Ages, and that's what does follow the fall of the Mycenaean world.

那么,这就是这个术语的含义,黑暗时代,它紧随着,迈锡尼文明的陨落到来

耶鲁公开课 - 古希腊历史简介课程节选

I switched over to what my Computer Science friends called the dark side

我转到了被学计算机的朋友们所称的黑暗学科，

从工学到经营学 - SpeakingMax英语口语达人

They hope to work out what dark matter is by the simple expedient of taking a look at it.

ECONOMIST: The dark side of cosmology

"In this case, it will always be an open question until we can pin down what dark matter is made of, " he said.

CNN: Space station detector gives first clues to 'dark matter'

We know there is dark matter - but we have to understand what this dark matter is made of.

BBC: Dark Matter: Experiment to shed light on dark particles