Two NASA astronauts began an epic battery swap on a spacewalk outside the International Space Station on Friday (June 26), the first of four excursions to update the outpost.
NASA astronauts Chris Cassidy and Bob Behnken, both veteran spacewalkers performing their seventh extravehicular activity (EVA), traded in three aged nickel-hydrogen batteries for two more efficient lithium-ion batteries, easily completing the job before Your spacewalk will conclude in 6 hours, 7 minutes at 1:39 pm EDT (1739 GMT)
The duo finished the job so quickly that in their fifth hour, they began prep for their next spacewalk, scheduled for Wednesday (July 1), which will include another set of battery replacements. During Friday’s spacewalk, the duo removed two additional nickel-hydrogen batteries from service, the batteries that were scheduled for July 1, and set them aside for future disposal.
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The newly installed lithium-ion batteries were working well as the crew completed their spacewalk tasks, according to a NASA Television report during the spacewalk.
Behnken and Cassidy are among NASA’s most experienced spacewalkers, having faced their share of complex and emergency situations on EVAs. During Cassidy’s last mission in 2013 (Expedition 35/36), he helped track an urgent ammonia refrigerant breakdown and assisted in Rescuing European Space Agency astronaut Luca Parmitano from life-threatening spacesuit water leak. Behnken’s last three spacewalks, during the STS-130 space shuttle mission in 2010, saw him assist in Install the Tranquility module It houses the wraparound window of the dome, as well as exercise equipment and a bathroom.
Friday’s spacewalk was no less vital, as Cassidy and Behnken carefully removed and replaced the S6 truss batteries that power a pair of space station solar panels. Crews in orbit require power for almost everything they do in space, from cooking to conducting experiments. Battery replacements are necessary to power the space station through its mission extension planned for 2024. (Space station partners they are discussing an extension until 2028 at least as the orbiting laboratory opens for more business opportunities. Some parts of the station are almost 22 years old.)
Astronauts switched to the power of the inner suit at 7:32 am EDT (1132 GMT), beginning the spacewalk. In a matter of minutes, veteran space walkers quickly moved outside and overcame the usual small issues that accompany maintenance work in space.
Cassidy’s mirror on her left wrist floated inadvertently as she exited the crew’s hatch into space, but posed no risk to astronauts or spacewalk procedures, officials said on NASA television. Cassidy had a rearview mirror on his right wrist to look at the switches and actuators on his space suit that would not otherwise be easily visible to him, authorities added. Each mirror is only a tenth of a pound by mass.
Behnken, exiting the hatch near Cassidy, briefly struggled with a portable footrest (PFR) when he started heading to the workplace. “PFR is sticky,” said Behnken as he struggled with the device to carry it.
Hand in hand, Behnken headed first to the S6 lattice with Cassidy stopping a bit longer on a nearby outer platform in the clutches of the robotic robot Canadarm2. The new one, 428 pounds. (194 kilograms) the batteries were sent to space aboard the ninth Japanese transfer vehicle H-II (HTV) in Mayand moved to the workplace using robotic operations.
“OK Bob [I’m] You’ll finally get away with it, “Cassidy said when she reached the truss, about 50 minutes into the spacewalk.
“That’s good,” replied Behnken.
Behnken and Cassidy (the latter with red stripes on his spacesuit designating him as the primary spacewalker) worked closely at a single workplace for most of their excursion. For hours, the crew carefully worked back and forth between the armor and the battery area, placing the new batteries in place while storing the old batteries on a pallet for later disposal.
As the astronauts moved the bulky batteries as a team, the duo carefully reminded themselves of who controlled the movement, chanting directions from one side to the other. “I am in control of the battery,” one would say, every few seconds, and the other repeats: “You are in control.”
The battery replacement was completed two hours ahead of schedule, with astronauts advancing forward during the latter part of the spacewalk. In addition to intermittent radio communication problems and a camera sticker button, the astronauts reported that their work went smoothly.
“My radio has been on fire,” Behnken said at 4.5 hours on the spacewalk.
An hour later Cassidy reported difficulties with a camera shutter. “Bob, I don’t like this camera,” she said as she took closing photos of her workplace.
The space station’s orbit periodically pulls it out of sunlight, requiring batteries to store and deploy electrical energy as it enters and leaves the orbital darkness 16 times a day. Nickel-hydrogen batteries it only has about 6.5 years lifespan and require more frequent replacements than lithium-ion batteries, which are rated to last 10 years. The original batteries in the P6 truss, for example, were replaced by more nickel-hydrogen batteries in 2009 and 2010 before being upgraded to lithium-ion a decade later.
The location of the S6 truss is quite far from the core of the station, putting it out of the reach of robotic helpers and requiring space walkers to do most of the battery replacement work. The closest battery replacements in the S4 and P4 trusses were done primarily through robotic operations, according to NASASpaceflight.com; In contrast, the P6 truss battery replacements require a lot of astronaut work in 2019 and 2020.
Replacing the space station’s previous set of 48 nickel-hydrogen batteries with 24 lithium-ion batteries has been a multi-year process for astronauts. The first set of lithium-ion battery related spacewalks occurred in 2017 and the matter was last addressed during a series of spacewalks for women that completed in January 2020. If everything goes according to plan, Cassidy and Behnken will finish the battery replacements during their next spacewalk.
The spacewalkers were assisted by a mission control team in Houston, including capcom (spacecraft communicator) and Canadian Space Agency astronaut David Saint-Jacques, and NASA Ground astronaut Jasmin Moghbeli, Ground IV (spacewalk astronaut communicator). In space, NASA astronaut Doug Hurley starred in the suit, sparking a fond memory of his wife and retired NASA astronaut Karen Nyberg.
“The last time @Astro_SEAL [Chris Cassidy] I did a space walk during Expedition 36, I was there to help him with the suit and the operations at the airlock. ” Nyberg said on Twitter Thursday (June 25). “Tomorrow, it will be my husband’s turn to get her and @AstroBehnken safely out the door!”
Cassidy, a former Navy SEAL, launched into space on a Russian Soyuz spacecraft April 9 as part of Expedition 62. He is currently the commander of the space station for Expedition 63. Former test pilot of the US Air Force Behnken flew into orbit on May 30, 2020 In the Demo-2 mission, the first SpaceX Crew Dragon spacecraft with astronauts on board. The Demo-2 launch from Florida was the region’s first astronaut mission since the last space shuttle mission, in 2011, and began NASA’s long-awaited commercial crew program to replace the shuttle.
Friday’s spacewalk was the 65th spacewalk in the US and the 228th overall spacewalk in support of the assembly, maintenance and upgrades of the space station, according to NASA.
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