Turning back to the mirror, Jenny saw a flash of light from the watch in the glass.

回头照镜子， 珍妮发现手表发出了一束光。

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If you are looking up at the sky on a clear night and you see a sudden flash of light, it is probably a shooting star!

如果你在晴朗的夜晚仰望天空，突然看到一道闪光，那可能是颗流星！

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There was a flash of light in the distance.

远处灯光一闪。

《新英汉大辞典》

He said he could see the flash of light from Confederate guns along a line a kilometer long.

VOA: special.2009.12.17

The finger gesture that people use to dismiss the notifications can be distracting, as can the flash of light on the Glass itself.

CNN: Figuring out real-world etiquette for Google Glass

It says the flash of light comes not from any type of combustion -- as we typically think of explosions -- but rather by the glowing molten rock at the impact site.

CNN: Bright explosion on moon visible from Earth, NASA says

The most popular theory holds that dark matter is made up of relatively heavy particles which, when they encounter one another, "annihilate" with a flash of light that the Fermi telescope can see.

BBC: Fermi telescope may change to dark matter hunting