What's blue and white, squiggly, and suddenly appears in the sky?

If you know the answer, pop it on a postcard and send it to the people of Norway, where this mysterious light display baffled residents recently.

Speculation was that the display was the result of an embarrassing failed test launch of a jinxed new Russian missile.

The Bulava missile was test-fired from the Dmitry Donskoi submarine in the White Sea but failed at the third stage, said newspapers in Moscow.

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