NASA astronauts Peggy Whitson and Shane Kimbrough were taking a record-breaking spacewalk as they floated in the proximity of the International Space Station (ISS). Suddenly, a part of the micrometeoroid shield floated away from the ISS’s exterior.
When Kimbrough noticed the problem, the shield segment had already floated away. The array of shields was being installed on one of the ISS’s ports, specifically the Tranquility module.
Mission Control determined that the drifting shield was not hazardous to the mission or the ISS. Even if the piece of shielding was critical for the module, Whitson and Kimbrough fixed the issue with suggestions from flight controllers down on Earth, who proposed they installed a thermal shield they had removed earlier from a docking port.
It’s the first time NASA loses a micrometeoroid shield during a spacewalk.
Solving a problem in low-Earth orbit
Whitson and Kimbrough were installing four micrometeoroid shields on the Tranquility module, also known as Node 3. Coincidentally, that spacewalk would have made Whitson the most experienced female astronaut in history.
As both astronauts were working over 3 hours into the spacewalk, the shield floated away due to it being untethered, according to The Washington Post. Mission Control hurried to find a solution, as a significant portion of the module’s access point was left exposed.
The solution was to use a similar type of fabric and tie it using wires, similarly to how the shield was supposed to be installed. Each fabric segment weighs 18 pounds and is slightly larger than 5 x 2 feet in dimensions and 3 inches thick.
Expectations are that the fabric shield will degrade as it enters Earth’s atmosphere, burning itself in the process. There is a chance that the item will return to the ISS’s orbit and collide with it, which led Mission Control to monitor it for a while. After an hour and a half, it was determined that the piece of fabric would not likely collide with the station. The spacewalk was nearing its end as it hit the seven-hour mark.
On the other hand, Whitson broke the record of the highest accumulated spacewalking time for a woman. Breaking the previous record of 50 hours, 40 minutes, with hers of 53 hours and 40 minutes during her eight spacewalk, which is also a first for a female astronaut.
Tranquility’s purpose is serving as a system for life support and waste recycling abilities. The module provides the ISS crew with more oxygen for breathing, and it removes contaminants from the station’s inner atmosphere.
It is often overlooked that shielding spacecraft and astronauts against micrometeoroids are vital for space missions. For example, a satellite can be rendered useless by being hit with a piece of supersonic space debris, as most satellites are programmed to turn off after they have suffered a serious unbalance in their systems.
In 2012, a micrometeoroid impacted one of the ISS’s modules, the Cupola, which is frequented by ISS crew for better visibility and for taking photographs of Earth. Even if the windows, alongside most of the ISS’s exterior, are shielded against micrometeorite impacts, they tend to show signs of wear, even holes.
Source: The Washington Post