It also slows down more as you move faster, which means astronauts (宇航員) someday may survive so long in space that they would return to an Earth of the distant future.
出自-2011年6月聽力原文
英語六級真題
Although, over the years, Barbies had more than 180 different careers, including football coach, sign language teacher, ambassador, president and astronaut, her body shape hasn't changed much.
2017年12月六級真題（第一套）聽力 Section B
柯林斯高階英漢雙解學習詞典釋義
N-COUNT
航天員;太空人;宇航員
An astronaut is a person who is trained for travelling in a spacecraft.