求外研版初二上Module3Unit2的课文我要用那篇课文,就是讲宇宙的那篇:Scientiststhinkthattherehasbeenlife...快!
求外研版初二上Module3Unit2的课文
我要用那篇课文,就是讲宇宙的那篇:Scientiststhinkthattherehasbeenlife...
快!
求外研版初二上Module3Unit2的课文我要用那篇课文,就是讲宇宙的那篇:Scientiststhinkthattherehasbeenlife...快!
求外研版初二上Module3Unit2的课文
我要用那篇课文,就是讲宇宙的那篇:Scientiststhinkthattherehasbeenlife...
快!
ScientiststhinkthattherehasbeenlifeonEarthformillionsofyears.However,wehaven'tfoundlifeonotherplantsyet.Whynot?
TheEarthisaplantanditgoesaroundtheSun.Noneofthemhasanenviormentwithair,sopeopleandthingscannotgrow.TheSunanditsplantsarecalledthesolarsystem.Thesolarsystemisasmallpartofourgalaxy.
Thestarsweseeatnightarethesunsinothersolarsystems.Therearemorethan200billionstarsinourgalaxy,calledtheMikyway,andourSunisonlyoneofthem.
Butscientistshavediscoveredmanyothergalaxiesintheuniverse.Theyarealongwayawayandtherelighthastravelledformanyyearstoreachus.Itishardtounderstandhowlargetheuniverseis.
Scientistshavelotsofspacecrafttolookatotherplantsinoursolarsystem,andsomespacecrafthavegonebeyondthesolarsystem.However,noonehasdiscoveredanylifeinspaceyet.
Butwhyhasnoonefromotherplantssentusamessage?Havetheytriedtosendimformationtous?Withsomanystarsintheuniverse,arewealone,oristherelifeoutthereinspace?Wedon'tkonw...yet.