Two astronauts flew in front of the International Space Station on Friday for the first of four spaceflights to fix a $ 2 billion cosmic ray detector, working hard to prepare an invasive surgery device to resuscitate. to cool and extend the life of the instrument by testing the composition of the universe.
"We're doing what can be considered an open-heart surgery on this amazing experiment," said Italian astronaut Luca Parmitano, the current commander of the space station.
The patient at 7.5 tonnes in this case is the Alpha Magnetic Spectrometer, or AMS, the most expensive scientific instrument on the space station and one that was not designed to service the orbit. As such, "surgery" is considered one of the most challenging of repair and upgrade work..
"It's definitely at the top of the list, if not the top," said Tara Hohim, AMC's director of repair at the Johnson Space Center in Houston.
Hovering at the station's Quest airport, Parmitano and NASA astronaut Drew Morgan shifted their spacecraft's energy from the battery at 6:39 p.m. EST to officially launch its ninth year.
The last time Parmitano walked into space in July 2013, his suit malfunctioned, overflowing the helmet with water and forcing an immediate return to the station's air traffic. NASA has developed procedures to prevent duplication and no similar problems since then.
The main purpose of the space on Friday was to prepare the AMC for its planned operation, deploying tools and equipment before removing the debris shield, to give them access to the instrument's thermal control system.
After carefully dumping the debris shield across the ship, the spacecraft attached two attachments to help them move around the device and, reaching the AMS, tore half a dozen postal links and cut a cable to overlap the insulating blankets.
The work went much faster than expected and the astronauts were able to work through several items initially planned for the second spacecraft next Friday. Then the real repair work will begin. The third and fourth spaceships will be officially scheduled after managers evaluate the results of the first two outings.
Parmitano and Morgan returned to the air, closed the gap and began repressing at 1:18 p.m. to round off the six-hour 39-minute spaceship, the 222th since the assembly station began in 1998, the ninth so far this year, the third for Parmitano and the fourth for Morgan.
"I have to tell you, you made the team team terribly happy and proud of you guys today, just great, great work," Canadian astronaut Jeremy Hansen of Mission Control radio broadcasts. "We are very, very pleased to be moving forward, bringing back the Alpha Magnetic Spectrometer and things. So congratulations to you all."
It took engineers and astronauts four years to come up with a cost-effective repair plan, developing some 20 of their own tools and testing procedures during more underwater training. Parmitano and Morgan completed seven exercises with full training before starting at the station in July.
"We had to move away and figure out how to create a job, we had to build new brackets to install existing hardware, we had to deal with existing sharp edges, and in many cases, we created new edges using tools that had sharp edges on them. "Hokim said.
"We did as much as we could to minimize that risk to the crew member and then, of course, to (repair) the payload itself," she said. "But they are certainly very challenging and technically difficult EVA."
Launched in 2011 on the next mission to the space shuttle, the Alpha Magnetic Spectrometer, is one of the most expensive scientific instruments ever launched in space.
It is built around a powerful electromagnet that bends trajectories of electrically charged cosmic ray particles created by supernova explosions and other events with extreme energy states, allowing researchers to study trajectories to characterize their speeds and energies.
The goal is to learn what happened to the antimatter that is thought to have been created at the birth of the cosmos in the Big Bang, to learn more about the unseen dark matter that penetrates into space, and eventually to gain insight into the nature of the dark, mysterious energy. a repulsive force that speeds up the expansion of the universe.
Designed to operate for only three years, the AMS proved to be longer than expected, revealing more than 145 billion cosmic rays over eight and a half years of operation. But the instrument has been haunted in recent months by the incredible failures of four small pumps needed to circulate carbon dioxide through sensitive detectors.
To fix the AMS, Parmitano and Morgan will have to cut eight small cooling lines and glue in, or "blur", new lines leading to a custom-built replacement pump module, launched to the station earlier this month. . The pump module will be installed during the third spaceship.
"We will reduce the pipes, and then merge them with other pipes (launched) from Earth and install a completely new pump to help with the cooling operation, keeping the magnet cold so the Alpha Magnetic Spectrometer can operate," Parmitano said. "This is really the first time we have tried any of these activities."