This is because of conservation of angular momentum, the same property that causes ice skaters to spin faster if they draw their arms in.

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China's best ski slopes are at the nearby Yabuli Ski Resort, while in Harbin itself the Songhua River provides space for ice skaters and ice hockey games.

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From 3:30 pm to 6 pm, the Prenestina Philharmonic orchestra will play some of the most famous pieces by Verdi, Tchaikovsky, Strauss and Gounod to accompany a variety of performances, including by world-champion ice skaters Alessandro Spigai and Anna Remondini (on roller-skates), stilt-walkers and traditional dancers.

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The pair, who 24 million viewers saw win Olympic gold medals in 1984, will look after aspiring celebrity skaters on live championship Dancing on Ice.

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But after a season-long spike in goal-scoring, teams figured out that if they dropped their skaters back on defense quickly, making the middle of the ice as crowded as a Times Square subway platform, they could keep opposing players on the perimeter of the rink.

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