CAPE CANAVERAL, Fla., Dhu-AlQa'dah 29, 1437, Sep 1, 2016, SPA -- Two U.S. astronauts went for a spacewalk outside the International Space Station on Thursday to pack up a spare cooling radiator and install a high-definition television camera outside the orbiting laboratory, a NASA TV broadcast showed, Reuters reported. Commander Jeffrey Williams and Flight Engineer Kate Rubins left the station's airlock around 8 a.m. EDT (1200 GMT) as the station sailed 250 miles (400 km) above Earth. "It's good to be out here," said Rubins, 37, who was making her second spacewalk in two weeks. On Aug. 19, Rubins and Williams installed a docking system to enable commercial space taxis currently in development to park at the station, breaking Russia's monopoly on crew transport. Test flights of Space Exploration Technology's Crew Dragon capsule are expected to begin next year, followed by the debut of Boeing's CST-100 Starliner in 2018. It was not immediately known what impact, if any, the loss of a SpaceX Falcon 9 rocket during a routine prelaunch test in Florida on Thursday would have on the company's other programs. For Thursday's spacewalk, which was scheduled to last six and a half hours, the astronauts headed to far end of the station to retract a radiator that was last used in 2012 to trouble-shoot a cooling system leak. Folding up the panel will protect it from strikes by micrometeors and orbital debris, NASA flight director Zeb Scoville told reporters during an Aug. 24 press conference. -- SPA 20:12 LOCAL TIME 17:12 GMT www.spa.gov.sa/w