the decontamination. you know, explain sure. okay, good. okay. the outside cooling loop uses ammonia as the working fluid and at very high pressure. so when they replace the broken pump module with the new one, they had to reconnect those lines, those fluid lines to reconnect the ammonia to the box, to the pump module. so they were having trouble getting those connections made, and that s when one of the connectors started leaking ammonia out. those were the white flakes you saw. of course, the liquid ammonia under high pressure comes out into the vacuum of space and turns into a solid. it freezes. so that s why you heard them calling it snow. it s snowing. it looked like snowflakes kind of coming out of that connector. now, it gets on their suits. you know, needs to be baked out to make sure you don t bring that ammonia back into the cabin inside of the international space station and release ammonia inside. that s why they re taking the extra precaution in addition to baking
this mission is to replace one of two cooling loops that failed on the station, forcing the crew to conserve power. if they lose the second cooling loop, they would have to abandon the station. they have done this kind of work before. this would be the first spacewalk since an astronaut nearly drowned in his helmet last july. at 230 miles above the earth, recritical component on the station. there is an ammonia risk whenever replacing these cooling loops. the job, replace the bad pump with a spare. doug was the last astronaut to work on the pump in 2010. this week he recorded a video showing the space station crew how to go about the repair mission. our advice to them and the crew agreed, we re going to go slow, methodical, step by step, challenge response. with their space suits
systems on the international space station. it malfunctioned this week. the pump on the cooling loop automatically shut down. that system makes sure equipment on iss stays cool and keeps working. nasa officials said yesterday they tried one fix that didn t work, and they may have to do a space walk to replace it. i am joined now by michael nasamino, a nasa astronaut and visiting professor at columbia university engineering school. mike, it s a pleasure and honor to have you on the program. tell me this. thanks for having me. from the scale of things that can go wrong in a space station, where does this rank in severity and concern? i would say probably somewhere in the middle. it s not a really bad thing. there are plenty of things that can happen to you that are a lot worse, but it s also not a very good thing. as you explained, we have two cooling loops, one is down. luckily, we have the second one to keep everything working correctly, so no one is in any danger. science can st
problem on the ground, and they re working with the crew. the crew is saying what can we do to help? they understand the systems, they re ready to go, and they re working closely with the control center. bill: a cooling loop does what on the international space station? you ve got all this equipment humming along, it builds up heat just like a television set or a refrigerator this your house. believe it or not, it builds up heat. you ve got to get that heat away. so ammonia is used just like a car has antifreeze, ammonia takes it away and radiates it to space. your equipment can overheat, and that s not a good thing. bill: terrific meeting you. my pleasure. bill: an honor. merry christmas. thank you. martha: stunning new accusations of stonewalling after the benghazi terror attack that left four americans dead. a new report suggests the security firm on the ground was told not to talk to the media. why? when we come back.
i hope she s sitting that one out. i wonder if she is a member. right. moving to south africa this morning thousands of mourners from all corners of the world are paying their respects to nelson mandela. today is day two of his lying in state at the union building, the site he was sworn in as the country s first black president nearly 20 years ago. he will be buried in his childhood village of qunu. putting an unfortunate blemish on nelson mandela s memorial, news that archbishop desmond tutu s home was robbed while he attended the memorial on tuesday. no arrests have been made and no details released. police say it is the third time in recent years the thieves have targeted him. nasa is considering an emergency space walk to repair a problem on the space station. an external cooling loop shut down yesterday. it is designed to keep the equipment inside and outside of of the station cool. the crew is not in danger. they haven t done a space walk since earlier this year. the