外星人

关于浩瀚宇宙深处是否存在智慧外星人文明的科学猜想，激励着一代代天文学家不断向深空发射探索信号。

guān yú hào hàn yǔ zhòu shēn chù shì fǒu cún zài zhì huì wài xīng rén wén míng de kē xué cāi xiǎng, jī lì zhe yí dài dài tiān wén xué jiā bù duàn xiàng shēn kōng fā shè tàn suǒ xìn hào.

Scientific conjectures about whether there are intelligent alien civilizations deep in the vast universe have inspired generations of astronomers to continuously send exploration signals into deep space.