NASA astronaut Andrew Morgan and European Space Agency astronaut Luca Parmitano are back in the International Space Station after completing the third in a series of complex spacewalks aimed at fixing an experimental physics device created to detect antimatter in cosmic rays.
AMS is a unique cosmic ray sensor, the sole magnet in distance, taking information on the International Space Station because of 2011.
The duo switched their spacesuits to battery power - the official beginning to all spacewalks - at 6:31 a.m. ET on Monday morning.
They re-entered the ISS after six hours, after installing a new cooling system sooner than expected.
NASA compared the series of four spacewalks - the most complex since the Hubble Space Telescope missions - with heart bypass surgery because they are created to bypass the old, degraded pumps. The exit in Monday's space is the third in almost three weeks for the couple and is the culmination of years of work to fix the Alpha Magnetic Spectrometer. If the new plumbing holds, the instrument should last the entire life of the space station, or another five to 10 years. Data collected by the AMS could help scientists determine the mysterious makeup of dark matter, which accounts for most of the mass in the universe.
The $2 billion spectrometer was never meant for hands-on repairs like this and was created to last just three years.
"AstroLuca" installed the new cables and connected the new pump to the tubes of the old device.
In addition to successfully repairing the AMS's cooling system, the two spacewalkers also completed several get-ahead tasks.
The installation will be checked during the next spacewalk. "The flight control team on Earth initiated power-up of the system and confirmed it is receiving power and data".