In the vacuum of space, the amount of debris—spent rocket stages, splintered satellites, micrometeoroids—numbers in the millions, all zooming about, often at 17,000 mph speeds. They’re also constantly hitting each other in a tsuris of exponential littering. Most of these pieces are tiny, and many are not anywhere near the altitude of the ISS. But the area isn’t completely clean.
Медведев вышел в финал турнира в Дубае17:59
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Tony Jolliffe BBC
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中国科协、教育部日前印发《关于进一步加强高等学校科普工作的意见》，提出到2030年实现高校科普工作全覆盖。根据意见，到2030年，高校科普工作体系将更加完善，高校科普地位作用更加凸显，科学素质和能力培养导向更加鲜明，高校社会化科普服务效能更加彰显，服务国家创新驱动发展的贡献度进一步提升。