Experts say it's partly to see how far the weapons can fly and what they're capable of.

专家认为，部分原因是要测试一下导弹飞行的距离和导弹的力。

OK. So, scientists criticised this plan to fly more sustainably.

好的。因此，科学家们批评了这个更持续飞行的计划。

Some suggest that the elusive animal is therefore not a bird at all, but a flying reptile unknown to science.

因此，一些人认为这种难以捉摸的生根本就不是鸟类，而是科学无法明白的飞行的爬行生。

It can also provide clues about what is causing bee colonies to collapse, and monitor the inevitable march of climate change.

飞行的传感器以提供线索，让人了解蜂群为何崩溃紊乱，同时也监测来势汹汹的气候变化进行到了什么程度。

See, this is why I don't leave the house because some unknown flying reptile bird creature could just swoop down and pluck out my eye. Ca-caw!

看吧，这就是我为什么不喜欢离开屋子，因为一些未知的飞行爬行生会俯冲而下然后拔出我的眼球。嘎嘎。

NASA has a program looking at sustainable fuels for supersonic flight, because that's going to be another requirement to truly make it a viable option in the future.

美国国家航空航天局有一个研究超音速飞行持续燃料的项目，因为这将是未来真正实现超音速飞行的另一个必要条件。

The UK Government's target is completely sustainable flying by 2050, but researchers found that more than half of all British farmland would be needed to grow the plants to make the biofuel.

英国政府的目标是到 2050 年实现完全持续的飞行，但研究人员发现，要种植制造生燃料的植，需要英国一半以上的农田。

She said Tuesday's flight shows a sustainable flight is possible, but the difficulty is in producing enough of the new fuel " so that we're flying more sustainable aviation fuel every day."

她说，周二的飞行表明持续飞行是的，但困难在于生产足够的新燃料，“以便我们每天都使用更持续的航空燃料”。

It succeeded, and now the Crew Dragon is the first vehicle that NASA has certified to carry humans since the Space Shuttle — and the first private spacecraft ever to receive that designation.

现在 Crew Dragon 是 NASA 自航天飞机以来第一个经认证载人的飞行器， 也是有史以来第一个获得该称号的私人航天器。