“宇航”的英语可以翻译为：astronavigation，space navigation ...

轮船的航线是标在航海图上的.The course of a ship is marked on a chart.领航员在航海图上标出船的航线.The navigator charted the course of the ship.船长在航海图上标出了这个区域,在这一区域里航行是相当安全的.The captain charted this area out and it's quite safe to sail in it....

“开航”的英语可以翻译为：ecome open for navigation，be open to navigation，set sail，sail，disembogue ...

“航空术”的英语可以翻译为：avigation，aeronautics，aviation ...

我们现在正接近这我非常喜爱巡航的一部分.We are now approaching the part of this cruise that I most enjoy....