In 1783, hot air balloons became the first viable option ... from cloth balloons and open baskets to polyethylene balloons and metal pressurized gondolas that allow for high-altitude atmospheric ...
Mainland scientists have discovered a "super material" that is as light as a balloon yet as strong as metal, which could be developed by the mainland's military into armour that protects troops ...
一些您可能无法访问的结果已被隐去。
显示无法访问的结果