How to watch first NASA spacewalk of 2019 during International Space Station upgrade
The live show can be watched on NASA Live.
Ms McClain and Mr Hague will replace nickel-hydrogen batteries that power a section of solar arrays.
The batteries will be replaced by lithium-ion versions which NASA said are newer and more powerful, NBC News reported.
The work is part of a huge effort to replace the space station’s power system which began in January 2017.
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