Two NASA astronauts have set out on a spacewalk to carry out repairs at the International Space Station (ISS).<br /><br />Part of the ISS cooling system automatically shut down last week after detecting abnormal temperatures. <br /><br />While NASA says the ISS crew are not in danger. But the partially-running cooling system is not enough to keep supporting all the laboratories on the US side of the station, so needs to be fixed.<br /><br />On the first of three planned spacewalks to rectify the problem, American astronauts Rick Mastracchio and Mike Hopkins are due to disconnect a pump containing a faulty valve.<br /><br />“Beautiful day, awesome view,” were Mastracchio’s words as he opened the hatch to step out into space for the 6.5 hour outing.
