National holiday created to announce future space explorations as well as honor China's pioneers of space travel.

1. 从结构看，本句在created之前漏掉了was，应为被动语态结构：

National holiday was created to announce future space explorations as well as honor China's pioneers of space travel.

2. 动词不定式视为目的状语：to announce future space explorations as well as honor China's pioneers of space travel.

我重新翻译一下，供参考：

【翻译】设立国家性节日，旨在表彰中国太空旅行的先驱，以及宣告未来太空探险（的伟大目标）。