Mobile virus testing unit set up in central Athens (video)
A mobile testing unit for the coronavirus was set up in central Athens on Tuesday as Greece faces a resurgence of COVID-19 cases
President Trump to declare state of national emergency over coronavirus spread
He will reportedly call for federal aid for states to combat the virus
NASA drone ditches chase plane in milestone flight
This was the first flight of a remotely-piloted aircraft with airborne detect and avoid technology capable of meeting all of the FAA's "see and avoid" rules