Video: Expedition 50 spacewalk highlights

An unexpected, quickly-planned spacewalk is on tap Monday to troubleshoot a problem preventing the International Space Station’s robot arm transporter from reaching a worksite where it can be locked down, a requirement before a Russian Progress cargo ship can dock later in the week.

Space station commander Chris Cassidy and Robert Behnken floated back outside Tuesday for their fourth spacewalk in less than a month, completing preparations for future upgrades including the eventual installation of an airlock that will allow commercial experiments to be moved into and out of vacuum as required.

Astronauts Anne McClain and Nick Hague floated outside the International Space Station Friday to complete the installation of powerful new batteries in the lab’s solar power system, a complex task that began in 2017. Another set of batteries will be installed during another spacewalk next Friday.