Like fog around a street lamp, a reflection nebula shines only because the light from an embedded source illuminates its dust; the nebula does not emit any visible light of its own.

就像路灯周围的雾，一个反射星云的发光仅仅是因为嵌入其中的一个光源照亮了他的尘埃，星云本身并不发出任何可见光。

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The beads dissolve, a lamp illuminates the sample and a sensor records the results.

FORBES: Medicine Man