第一段詞匯解析①detect = discover, find。②in relative terms = relatively (speaking) , in relation to other things。③emit = send out。④ideal conditions = an environment which is perfect (for the development of life)。第二段詞匯解析①capable of = able to。②alternatively = on the other hand。③presence = existence。 第三段詞匯解析①在 because 引導的原因狀語從句中還有一個“ the further…system”作比較狀語從句。②小綠人這個單詞本身在英語語境中就是指代外星人，是想象的外星小綠人。Notes 學習筆記詞組歸納1.Milky Way2.in relative terms3.solar system4.far too5.depend on6.up to7.life forms8.at present9.in existence10.be capable of11.Hubble telescope12.because of13.dust particles14.look for15.outer space16.outer edge17.blot out18.in the first instance19.little green men20.in the realms of sth.21.science fiction