geeks. houston, we have a problem. different kind of problem than what you re thinking. american astronauts may have to do an emergency space walk to fix it. this is part of the international space station s cooling system. it has shut down. right now, we don t know what caused it or even exactly how they can fix it. joining me now is danny, former nasa astronaut. so dana, welcome, by the way. good afternoon, brooke. nasa, we know nasa hopes this software fix can help stop this valve from malfunctioning. if not, someone has to actually get out there and make the repair, so you are abastronaut, walk me through the dangerouses of heading outside the iss. well, the components that are in question as part of the external thermal control system, which is basically dissipating the heat from avionic systems, e electronics outside the space station as well as inside the habitable module. they have the capability to reject heat from the external