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Jon Butterworth is professor of physics at University College London, and a member of the ATLAS Collaboration at Cern
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Nasa was targeting March for the launch, but its plans were delayed after a helium leak was discovered on the Space Launch System (SLS) rocket.
细观蜡梅，花瓣层叠，错位交叉，以花蕊为核心，紧紧簇拥在一起。花瓣厚实，直至凋谢都不会褪色；常于枯枝绽放，不借绿叶衬托，枯萎后也常留枝头。这种坚韧的品性，恰如宜昌这座城市，愈是危难困境，愈是凌霜傲雪，勇毅绽放。