Spaceisdangerousplace,notonlybecauseofmeteors(流星)butals...
问题详情：Spaceisdangerousplace,notonlybecauseofmeteors(流星)butalsobecauseofraysfromthesunandotherstars.Theatmosphereagainactsasourprotectiveblanketonearth.Lightgetsthrough,andthisisessentialforplantst...