Two astronauts ventured in front of the International Space Station on Friday for the first of four spacewalks to repair a $ 2 billion cosmic ray detector for the composition of the universe.
"We will do an open-heart surgery on this amazing experiment," said Italian astronaut Luca Parmitano, the current Space Station commander.
The 7.5-ton patient in this case is the Alpha Magnetic Spectrometer (AMS), the most expensive scientific instrument aboard the space station that was not designed for orbiting. For this reason, the Operation is considered one of the most difficult since the beginning of the work to repair and upgrade the Hubble Space Telescope .
"It's definitely on top of the list, if not top," said Tara Jochim, the AMS repair manager at the Johnson Space Center in Houston.
Parmitano and NASA astronaut Drew Morgan hovered in the station's Quest airlock and switched their spacesuits to battery power at 6:39 EST to officially launch the ninthof the year.
The Last Time, Parmitano In July 2013 he was in space and his suit had a malfunction. He flooded his helmet with water and forced a return to emergency to the station airlock. NASA has developed procedures to prevent recurrence, and since then no similar problems have occurred.
The main objectives of the spacewalk on Friday were to prepare the AMS for its planned operation, align tools and equipment before removing a shield from deposits and gaining access
After the spacewalkers had carefully thrown the shield overboard, They attached two handrails to move around the device, cut half a dozen cable ties into the AMS, and cut a cord to fold back thermal insulation blankets.
The work went much faster than expected and the astronauts were able to work through several items originally planned for their second spacewalk next Friday. Then the actual repair work begins. The third and fourth spacewalk are officially scheduled after the managers have evaluated the results of the first two trips.
Parmitano and Morgan returned to the airlock, closed the hatch and began pressurizing at 13:18. To complete a six-hour 39-minute spacewalk, the 222nd since the deployment began in 1998, the ninth this year, the third for Parmitano, and the fourth for Morgan.
"I have to tell you, you've made the ground crew terribly happy and proud of you today, just excellent, excellent work," beamed Canadian astronaut Jeremy Hansen of Mission Control, "we're very, very happy with it How to get ahead and get the Alpha Magnetic Spectrometer up and running again. So, congratulations to you all. "
It took four years for engineers and astronauts to come up with a working repair plan Development of about two dozen custom tools and test procedures during several underwater training runs Parmitano and Morgan completed seven full-day training exercises before leaving in July
"We had to get started and figure out how to build a jobsite, we had to build new handrails to install on existing hardware, we had to deal with existing sharp edges and in many cases we create new sharp edges with tools, which have sharp edges, "Jochim said.
"We did as much as possible to minimize this risk for the crew member and then, of course, for the (repair) payload itself," she said. "But they are certainly very challenging and technically difficult EVAs."
Launched in 2011 as part of the penultimate Space Shuttle mission, the Alpha Magnetic Spectrometer is one of the most expensive scientific instruments ever launched into space.
] It is based on a powerful electromagnet that bends the trajectories of electrically charged particles of cosmic rays generated by supernova explosions and other extreme energy events, allowing researchers to study the trajectories and their velocities and energies characterize.
The Goal Is What to Learn This was done with the antimatter that was born in the Big Bang of the Cosmos to learn more about the invisible dark matter that permeates the room and possibly insights into the nature of the dark energy to win, the mysterious repulsive power that accelerates the expansion of the universe.
The AMS has been designed to last for just three years and has proven to be longer than expected. It has more than 145 billion cos detected microphone beams during eight and a half years of operation. However, the instrument has been affected in recent months by the staggered failures of four small pumps required for the circulation of carbon dioxide refrigerant through the sensitive detectors.
To repair the AMS, Parmitano and Morgan will have to cut eight small coolant lines and splices. New leads leading to a tailor-made replacement pump module launched into the station earlier this month. The pump module will be installed during the third spacewalk.
"We will cut pipes and then merge them with other pipes (started from Earth) and install a completely new pump to support the cooling work, keeping the magnet cold for the alpha magnetic spectrometer to work", said Parmitano. "It is really the first time that one of these actions is attempted."