To date, astronomers haven't seen asteroid families (that is, asteroids with a common source) in the Solar System older than about 3 billion years -- well after the star system came to be 4.5 billion years ago.
Todate,astronomershaven'tseenasteroidfamilies(thatis,asteroidswithacommonsource)intheSolarSystemolderthanabout3billionyears--wellafterthestarsystemcametobe4.5bi
NavigationsystemtoplaykeyroleinbuildingofadministrationcenterChina'sself-developedBeiDouNavigationSatelliteSystemwillseewiderapplicationinurbanconstruction,asaS
HIVispassedonthroughbodilyfluidslikeblood,whichcanmakeitdangerousforsurgeonstocarryoutoperationsoninfectedpatients.Tocopewiththisdifficulty,TheGeneralHospitalof
Researchers have found a planet orbiting the closest star to the Solar System, and it may be the closest possible home for life outside the Solar System, according to a study published online Wednesday in the journal Nature.
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