European Space Agency astronaut Luca Parmitano has been carrying out an epic spacewalk to fix a dark matter experiment that was never designed to be repaired.
The Italian spaceman, who teamed up with his NASA buddy Drew Morgan, took on one of the most difficult spacewalks in International Space Station (ISS) history and was watched carefully by scores of engineers and scientists on the ground.
Parmitano is sharing his mission with Euronews viewers as part of the Space Chronicles series.
The faulty experiment is called AMS-02, which has failing cooling pumps that could prevent it from being able to carry out its ground-breaking research. AMS-02 collects cosmic rays from distant corners of the universe in a bid to understand dark matter, the mysterious 'stuff' that makes up 85% of the mass of our universe but which nobody has ever managed to see or identify.
Everything about Friday's spacewalk was a challenge, and Parmitano and Morgan have been training hard for months to get ready.
No sortie from the ISS is without danger, but AMS-02 is on a part of the ISS that was not designed for servicing, and there are concerns that the astronauts could get snagged on parts of the spacecraft during their outing.
The six-hour spacewalk has been choreographed minutely. Every detail, down to the order in which tools and equipment are attached to the astronaut’s suits, is worked out in advance.
NASA astronauts Jessica Meir and Christina Koch — who recently carried out the first all-female spacewalk — will help the pair into their suits, which is an ordeal in itself because of weightlessness.
Once out of the airlock, the first task will be to do a ‘buddy-check’ to ensure all equipment is as it should be and to orient themselves in this new environment. The astronauts must always be tethered to specific Space Station supports, much like rock climbers or cave explorers. They will also frequently check their suits and gloves, which are the most likely to be damaged by sharp edges. Nobody wants to have a hole in their suit or become detached and float away.
The pair will then separate and find their own way to AMS-02. Parmitano will attach himself to the 16m long robotic arm while Morgan will take handrails and equipment to AMS by hand, using his hands to move along the Space Station’s exterior.
This first spacewalk — others are planned — will take around six hours. During that time, there will be no food and no toilet break. Water is supplied in a pouch with a drinking straw. The work is tiring as the astronauts fight against the pressurised suit that becomes stiff in the vacuum of space.
The pair will have the weekend to recover, before starting another busy week in humanity's orbiting space laboratory.