During a risky spacewalk, two astronauts successfully dodged over specks of highly toxic ammonia last Friday to repair the cooling system at the International Space Station. Toxic ammonias are utilized to cool the orbiting outposts' electronics.
Wearing their bulky spacesuits at 11:22 GMT, astronauts Scott Kelly and Kjell Lindgren floated outside the orbiting outpost a few minutes after (this is an hour ahead of the schedule) as per the live broadcast on NASA television.
The agency said that the goal of the spacewalk is to complete the final repairs of the cooling system and restore the external ammonia cooling system to its original configuration after it has been broken down three years ago. It can be recalled that there was a major leak in the ammonia cooling system, and in May 2013, they replaced the ammonia pump on the truss.
Early part of the repair, when they were disconnecting some of the equipment, the duo has reported flakes of ammonia. However, NASA commentator Rob Navias assured that it posed no harm to spacewalkers. Midway of the spacewalk, they were done topping off around 7.5 lbs (3.4 kilograms) each into a primary and backup tank.
Then they worked together to take out on residual ammonia in the plumbing line. After opening the valve, they went out of the way. They then inspected each other's suit to check for any ammonia flakes and thankfully found none.
If an ammonia flake hit them, they would have stayed outside the airlock to allow the ammonia to bake off. Last time's ammonia leak incidence made astronauts stay for another thirty minutes in the sun so that frozen crystals are vaporized and melt off, thus preventing toxic substances from getting inside the space station.
Last Friday's spacewalk went longer than expected. The mission control expected a six and a half hour walk, but the two lasted seven hours and 48 minutes.
Marking the 15 years of habitation of the International Space Station, the recent walk was the 190th. Mr. Kelly wants to help NASA study the effect of long-term space flight on the body and mind. He is now halfway of his year-long mission and is expected to return Earth in March 2016.
