NASA flight engineer Andrew Morgan and the commander of the space station’s Expedition 61, Luca Parmitano of the European Space Agency, conducted their fourth spacewalk and completed leak checks on their installation of a new cooling system meant to extend the lifespan of the externally attached Alpha Magnetic Spectrometer dark matter and antimatter detector (the AMS).
Twenty new tools were developed for installing the cooling system, which involved clean cuts of eight stainless steel tubes attached to the defective cooling system, and the welding of new tubes to them from the replacement system.
The scientific data collected by the AMS has proven so valuable that NASA scientists now aim to keep it operating for the full 11 years of a complete solar cycle in order to better understand the possible impact of solar radiation variation on astronauts traveling to Mars.
According to NASA, the goal of the cosmic ray particle collection is to help understand dark matter, which is thought to comprise 95% of mass-energy content of the universe, and to identify its sources and their role in the origin of the universe.