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，详情可参考safew官方下载
“Building is easy now. Knowing what to build, and what not to, is the hard part,” Knecht added.
Pulse-Code Modulation (PCM) — MDN Web Docs
"Launching radioactive material through the Earth's atmosphere brings safety concerns. You have to have a special license to do that, but it is not insurmountable," says Dr Simeon Barber, planetary science specialist at the Open University.