English: Astronaut Richard Arnold, STS-119 mission specialist, participates in the mission's first scheduled session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the six-hour, seven-minute spacewalk, Arnold and astronaut Steve Swanson (out of frame), mission specialist, connected bolts to permanently attach the S6 truss segment to S5. The spacewalkers plugged in power and data connectors to the truss, prepared a radiator to cool it, opened boxes containing the new solar arrays and deployed the Beta Gimbal Assemblies containing masts that support the solar arrays. The blackness of space and Earth's horizon provide the backdrop for the scene.