来自陈滨的问题
Menhavebeeninterestedinthestarseversincetheyfirstlookedupintothesky.someofthesestarsmayhavetheirownplanets.ifthatisso,wecanknowthatlifemayexistoneofthem.theproblemisthattheneareststarisfourlightyearsawa
Menhavebeeninterestedinthestarseversincetheyfirstlookedupintothesky.
someofthesestarsmayhavetheirownplanets.ifthatisso,wecanknowthatlifemayexistoneofthem.theproblemisthattheneareststarisfourlightyearsaway.Inotherwords,lightfromithasbeentravellingforfouryearsbeforeitfinallyreachesus.Maybenobodyfromearthwillevervisitthatstarbecauseitwilltakearocketahundredthousandyearstoreachit.
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2020-02-20 23:53