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The International Space Station Expedition 61 crew pauses for a photo as NASA Astronauts Jessica Meir and Christina Koch prepare to exit the space station to begin the first all-female spacewalk in history on Oct. 18, 2019. The astronauts replaced a faulty battery charge/discharge unit (BCDU) that failed to activate following the Oct. 11 installation of new lithium-ion batteries on the space station’s exterior structure. The BCDUs regulate the amount of charge put into the batteries that collect energy from the station’s solar arrays to power station systems during periods when the station orb…
