Russian cosmonauts Fyodor Yurchikin and Oleg Kotov spent their Wednesday improving the micrometeoroid protection on the International Space Station. Over the course of their 5-hour, 25-minute spacewalk, they attached a series of protective aluminum panels to the outside of the Zvezda module.
A wise precaution, it turns out.
The cosmonauts discovered there was already a bullet-sized puncture in the Zarya module, thanks to a direct hit from a micrometeoroid some time in the past. NASA astronauts have noticed several holes in the station's solar panels, but this is the first time one's hit so close to the crew's living quarters.
They don't know much about this impact. When it hit, how large it was, or how fast it was going. Images taken by the station crew are still being analyzed by NASA scientists.
In the past, micrometeoroids have impacted both the station and the shuttle - even a fleck of paint traveling at 6 km/second can cause damage. Part of the danger is the shape of the impact. When these slam into the station, they create a tiny puncture hole on the outside, but can leave a much larger wound on the inside.
And this was the whole purpose of Wednesday's spacewalk. The Russian-built Zvezda module had less protection against these kinds of impacts than the other pressurized components of the station, such as Zarya. These panels absorb and dissipate the impact from micrometeoroids, bringing this module up to code.
Perhaps a new code needs to be written.
Source: NASA Spaceflight
