Astronauts typically spend their time conducting science experiments from the safety and comfort of the International Space Station, but sometimes the job requires them to venture outside of the Earth-orbiting space lab for maintenance.
These extra-vehicular activities, more colloquially known as spacewalks, can last several hours at a time, and NASA astronauts Mark Vande Hei and Scott Tingle performed one on Tuesday to replace a worn-out gripping mechanism at the end of the International Space Station’s robotic arm.
Image Credit: NASA
Astronauts completed a similar spacewalk mission back in October, but only replaced one of the robotic arm's two gripping mechanisms. Tuesday's mission focused primarily on replacing the second one.
Before the astronauts could install the new part, they needed to remove the old one. Tingle purportedly wrestled a stubborn bolt while trying to remove the tired component, but some forceful persuasion eventually broke it loose.
With the old gripping mechanism removed, Vande Hei and Tingle set the new one in place and snugged down all the bolts that hold it to the arm. Upon tightening the last one, the astronauts concluded the 7.5-hour spacewalk and returned inside of the International Space Station.
Despite how much they accomplished, the job isn't finished just yet; another spacewalk will take place on Monday will tie up loose ends. Vande Hei will venture outside of the International Space Station once again for this mission, but JAXA’s Norishige Kanai will take Tingle’s place as Vande Hei’s assistant.
If all goes well, then the robotic arm should work like a charm for the expected operating life of the International Space Station. Astronauts use it to grab onto incoming resupply cargo ships that deliver fresh food and science experiments to the space lab's inhabitants from time to time.