因此，最好的观测点是海拔高、光线暗且干燥的地方。

The best observatory sites are therefore high, dark, and dry.

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这种激光器的相反工作模式才是它真正的新奇之处，其中大部分时间光线是打开的，但它在很短的闪烁及非常短暂的暗脉冲里关闭。

"What's really novel is that this laser works in the opposite mode, where most of the time the light is on, but it turns off in very brief flashes, very brief dark pulses," said Wiener.

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纽约大学研究人员制造出了一种使用不可见光照明的相机闪光灯，不会让人觉得眼花，在光线暗的情况下依然拍出高质量的照片。以下是相机工作原理。

NYU researchers create a camera flash that USES invisible illumination, blinding no one, but still taking high-quality pics in low-light situations. Here is how it works.

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