NASA tracking stadium-sized asteroid headed toward Earth WMBFStadium-sized asteroid to make ‘relatively close’ approach toward Earth at 3 million miles WGN TV ChicagoMassive asteroid 'taller than the Empire State Building' headed towards Earth WKRC TV CincinnatiAsteroid that may be the size of Empire State Building to zoom past Earth CBS NewsStadium-sized asteroid will swing 'close' by Earth on Saturday.