By looking at the layers of snow in their test hole, an experienced extreme skier can tell if there's likely to be an avalanche.

有经验的极速滑雪者看看测试洞里头一层层的积雪就知道会不会有雪崩。

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After the word leaked, "we started to celebrate somewhat, " enjoying good times at a local test pilot watering hole.

CNN: Where planes go to die

In the next decade, Genzel hopes the planned next generation of 30 meter-class telescopes will enable black hole astronomers to test general relativity around the event horizon itself.

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Of course, exploiting a hole is also the only way to test that it has been fixed, so those outside the inner circle will be forced to rely on the software vendor's say-so when they get fixes and patches.

BBC: How digital Armageddon was averted