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Watch live: Spacewalkers work to prep space station for future upgrades

STORY WRITTEN FOR CBS NEWS & USED WITH PERMISSION

Space station commander Chris Cassidy and Robert Behnken floated back outside Tuesday for their fourth spacewalk in less than a month, this one to complete preparations for future upgrades including the eventual installation of an airlock that will allow commercial experiments to be moved into and out of vacuum as required.

The astronauts originally planned four spacewalks to install replacement batteries in the station’s solar power system, but that work was completed ahead of schedule during three excursions on June 26, July 1 and July 16. The fourth spacewalk was replanned as a result and now includes a variety of unrelated tasks.

Floating in the Quest airlock, Cassidy and Behnken switched their spacesuits to battery power at 7:12 a.m. EDT to officially kick off a planned six-and-a-half-hour spacewalk, the 231st in station history, the seventh so far this year and the 10th for both astronauts.

The first item on the agenda was to install a robotics tool box on a rail-mounted carrier used to move the station’s robot arm from one worksite to another.

After that, Behnken planned to move to the lab’s right-side inboard set of solar arrays to remove a no-longer-needed handling, or “H,” fixtures, one of several that were used to lift and move the stowed arrays before launch. Cassidy planned to detach a second fixture on the far right side of the power truss.

All of them must be removed to make way for future power system upgrades. Behnken attempted to remove the first fixture during the July 16 spacewalk, but he was unable to pull it free. Engineers then developed new procedures and tools, including a 3D-printed wedge, that were expected to help the crew pull off the two fixtures.

Cassidy and Behnken then planned to make their way to the left side of the power truss to prepare the outer hatch of the Tranquility module — the same compartment that features the station’s multi-window cupola — for the later attachment of a commercial airlock.

The Bishop Airlock, designed by Nanoracks as a commercial venture, is scheduled for launch later this year aboard a SpaceX Dragon cargo ship. Once in place, the airlock will enable research payloads and equipment to be robotically moved into and out of the space station, exposing them to the space environment as required.

The airlock will be attached to the Tranquility module’s currently unoccupied outboard port. To make way for installation, Cassidy and Behnken planned to remove a thermal cover and protective shields, reposition a variety of cables and clean the common berthing mechanism’s attachment fittings.

Once the airlock preps are complete, Cassidy and Behnken will wrap up the day’s work by routing camera power and data cables and removing a damaged lens filter from an external camera assembly.

Assuming the spacewalk runs the full six-and-a-half hours, Behnken will move up to No. 3 on the list of most-experienced spacewalkers with more than 62 hours of EVA time 10 excursions. Cassidy’s mark will stand at nearly 56 hours, moving him up to eighth on the list.

With the spacewalk complete, the station crew will turn its attention to the launch and docking of a Russian Progress supply ship Thursday. The next major task after that will be preparations for Behnken and Douglas Hurley to return to Earth aboard the SpaceX Crew Dragon spaceship that carried them into orbit May 30.

The Crew Dragon, developed as a commercial venture, is the first piloted U.S. orbital since the final shuttle flight in 2011. Hurley and Behnken plan to undock from the station’s forward port the evening of Aug. 1 and to splash down in the Gulf of Mexico or the Atlantic Ocean off Florida’s east coast on Aug. 2 to close out a 64-day flight.

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Watch live: Spacewalk begins for another round of space station battery swap outs

STORY WRITTEN FOR CBS NEWS & USED WITH PERMISSION

Now in the home stretch of a complex, multi-year upgrade, two space station astronauts floated outside the lab complex Thursday and pressed ahead with the third of four spacewalks the current crew is carrying out to complete the replacement of aging batteries in the station’s solar power system.

Station commander Chris Cassidy and astronaut Robert Behnken began the excursion at 7:10 a.m. EDT, switching their spacesuits to battery power while still inside the Quest airlock. That officially kicked off the 230th spacewalk, or EVA, since ISS assembly began in 1998, the sixth so far this year and the 11th devoted to battery replacement work since 2017.

For identification, Behnken, call sign EV-1, is wearing a suit with red stripes while Cassidy, EV-2, is using an unmarked suit.

After checking safety tethers and collecting tools, the astronauts headed for the far right end of the lab’s power truss to continue work started during spacewalks June 26 and July 1 to replace 12 older nickel-hydrogen batteries at the base of the outboard set of solar arrays with six more powerful lithium-ion power packs.

The space station is equipped with four huge solar wings, two at each end of the power truss, that feed electricity into eight power distribution channels. Twelve nickel-hydrogen batteries at the base of each wing, six per power channel, keep the station functioning when it’s in orbital darkness.

Starting in January 2017, astronauts began replacing the old batteries with more powerful lithium-ion units. Because they are more efficient, only six lithium-ion batteries are needed at the base of each solar wing, along with circuit completing adapter plates to take the place of batteries that were removed but not replaced.

During spacewalks in 2017 and 2019, spacewalking astronauts replaced all 24 nickel-hydrogen batteries used by the left and right inboard arrays. The left-side outboard solar wing was upgraded during spacewalks in 2019 and earlier this year, leaving just the right-side outboard set — 12 batteries feeding two power channels — for Cassidy and Behnken.

They completed the battery work for one power channel during their two earlier spacewalks.

During Thursday’s outing, they planned to remove five of the six remaining nickel-hydrogen batteries and to install all three of the remaining lithium-ion units, along with a final three adapter plates. They also planned to install a high-definition camera boom on the power truss.

Two of the new batteries should be connected by the end of the spacewalk. The final new battery will be tied into the power channel next week, after the last nickel-hydrogen battery is removed.

NASA planners originally thought the battery work would take two spacewalks per power channel, but Cassidy and Behnken ran well ahead of schedule during their first two EVAs and most of the battery work was expected to be completed Thursday.

During next week’s spacewalk, the astronauts plan to finish the battery work; make preparations for installation of a commercial research airlock; install a tool storage box; and remove two of six no-longer-needed ground-handling fixtures at the base of the solar wings to clear the way for future upgrades.

Assuming the final two spacewalks run exactly six-and-a-half-hours each as planned, Behnken will move up to third on the list of most experienced spacewalkers with 62 hours and 41 minutes of EVA time over 10 outings. Cassidy’s 10-spacewalk mark will stand at 56 hours and 22 minutes, moving him up to eighth in the world.

Cosmonaut Anatoly Solovyev holds the all-time spacewalk record with 78 hours and 21 minutes over 16 EVAs. Retired astronaut Michael Lopez-Alegria is second with 67 hours and 40 minutes over 10 excursions.

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Spacewalkers begin another round of battery replacement work

STORY WRITTEN FOR CBS NEWS & USED WITH PERMISSION

Picking up where they left off last week, two space station astronauts ventured back outside the outpost Wednesday to continue the replacement of aging batteries in the lab’s solar power system. Two more spacewalks later this month should complete the multi-year project.

Station commander Chris Cassidy and Crew Dragon astronaut Robert Behnken, floating in the Quest airlock, switched their spacesuits to battery power at 7:13 a.m. EDT to kick off their second spacewalk in five days, the 229th in station history and the eighth overall for both astronauts.

After checking safety tethers and collecting their tools, the astronauts floated outside and headed to the far right end of the space station’s power truss for another round of battery replacement work.

The space station is equipped with four huge solar array wings, each one feeding electricity into two circuits, or power channels. Each of the eight power channels originally included six nickel-hydrogen batteries — 48 in all — to provide electricity when the station is in orbital darkness.

But the original batteries are wearing out, and NASA is in the process of replacing all 48 with 24 more powerful lithium-ion power packs and circuit-completing adapter plates to take the place of batteries that were removed but not replaced.

During spacewalks in 2017, 2019 and in January this year, 36 old batteries in three of the four sets of solar arrays were replaced. Cassidy and Behnken are working to replace a final set in the station’s right-side outboard arrays.

Last Friday, they removed five of the six nickel-hydrogen batteries in one of the outboard power channels and installed two of three lithium-ion batteries and two of three adapter plates in their place.

During Wednesday’s work, they planned to finish power channel 1B and to loosen bolts securing batteries in power channel 3B. Before calling it a day, the astronauts planned to route cables for a new wireless communications system and to remove a no-longer-needed fixture on the power truss.

If all goes well, Cassidy and Behnken will venture back outside later this month to continue the battery swap outs for the final power channel, 3B. A fourth spacewalk is expected after that to finally finish the job.

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Cassidy, Behnken begin final series of space station battery upgrades

STORY WRITTEN FOR CBS NEWS & USED WITH PERMISSION

Astronauts Chris Cassidy and Bob Behnken work outside the International Space Station on Friday. Credit: NASA TV/Spaceflight Now

Two astronauts floated outside the International Space Station early Friday for the first of four planned spacewalks to wrap up a complex multi-year job to replace 48 aging batteries in the lab’s solar power system with 24 more powerful lithium-ion units.

Getting off to a fast start, Chris Cassidy and Robert Behnken ran well ahead of schedule throughout the day, completing all of their planned tasks and starting work originally planned for the next spacewalk in the series next Wednesday.

“I think we’ve done enough for one day,” one of the spacewalkers quipped before heading back to the airlock to wrap up a six-hour seven-minute excursion.

The battery replacement work began in January 2017 and based on Friday’s results, the astronauts should be able to complete the work next month, ensuring smooth, reliable power distribution through the rest of the decade if not beyond.

“I think it’s safe to say, barring any unforeseen type of failures, we’ll be good on batteries for a number of years to come,” said Kenny Todd, deputy space station program manager at the Johnson Space Center in Houston. “The longevity of the new technology batteries gets us well out through what will most likely be the end of the program.”

Floating in the Quest airlock module, Cassidy and Behnken switched their spacesuits to battery power at 7:32 a.m. EDT to officially kick off the 228th EVA in station history, the fourth so far this year and the seventh for both astronauts.

Assisting with the lab’s robot arm from inside the station were Douglas Hurley, Behnken’s crewmate aboard the SpaceX Crew Dragon ferry ship that carried them to orbit last month, and cosmonaut Ivan Vagner, who launched aboard a Soyuz on April 9 with Cassidy and cosmonaut Anatoly Ivanishin.

Floating out of the airlock, Cassidy reported that a small wrist mirror, used to help him read spacesuit displays that cannot be seen directly, had somehow worked loose and drifted away at about a half a mile per hour. Tipping the scales at just a tenth of a pound, the lost mirror posed no threat to the station or the crew, and in any case Cassidy had a spare.

NASA is wrapping up the replacement of all 48 of the space station’s older-generation nickel-hydrogen batteries with 24 smaller-yet-more-powerful lithium-ion units, along with circuit-completing “adapter plates” to fill in for batteries that were removed but not replaced. The adapter plates also provide long-term storage locations for several of the old batteries.

The new batteries are arranged in sets of six in integrated electronics assemblies, or IEAs, at the bases of the station’s four main solar array wings. Each wing is made up of two extendable blankets of solar cells and the electricity they generate is delivered throughout the station using eight electrical buses, or channels, two per IEA.

Batteries in each IEA store power generated when the arrays are exposed to sunlight and then provide the electricity needed to keep the station operating during the lab’s passes through Earth’s shadow.

The inboard right-side arrays are part of the starboard 4, or S4, truss segment, providing power to channels 1A and 3A. The inboard left-side arrays are part of the port 4, or P4, truss segment supplying power to channels 2A and 4A.

In 2017, spacewalkers replaced the 12 inboard S4 solar array batteries with six lithium-ion units and in March 2019, the 12 inboard P4 batteries were replaced by another six LiOH batteries.

For all of those replacements, the station’s robot arm had the reach necessary to assist the astronauts with battery relocations and unbolting and only four spacewalks were required. The outboard arrays and batteries pose a more difficult challenge.

During two spacewalks last October and another two more this past January, spacewalkers replaced the batteries at the far left end of the station’s truss — P6 — for power channels 2B and 4B. The batteries in channel 4B were installed during NASA’s second and third all-female spacewalks.

Because the outboard work site is so far from the robot arm’s outermost anchor point, four spacewalks were required because the astronauts had to manually move batteries back and forth between a storage pallet and the integrated electronics assembly where they were installed.

Cassidy and Behnken plan to carry out four essentially identical spacewalks to replace the 12 nickel-hydrogen batteries in the outboard right-side set of arrays with six lithium-ion units, three powering channel 1B and three used by channel 3B.

During Friday’s excursion, the astronauts removed five of the six older-generation batteries in the 1B circuit, installed two new batteries and two adapter plates. During next week’s spacewalk, the final nickel-hydrogen battery in the 1B circuit will be removed and a third lithium-ion unit will be installed along with one more adapter plate.

During two spacewalks next month, Cassidy and Behnken plan to replace the batteries in power channel 3B.

But those spacewalks will depend in part on how the first two go and the status of plans to bring Behnken and Hurley back to Earth in the Crew Dragon ferry ship around Aug. 2. If problems crop up, the final two spacewalks could be deferred and carried out by a future station crew.

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Astronauts gear up for spacewalks amid planning for August Crew Dragon return

STORY WRITTEN FOR CBS NEWS & USED WITH PERMISSION

NASA astronauts Chris Cassidy and Bob Behnken work with their spacesuits ahead of the first in a series of spacewalks scheduled for Friday. Credit: NASA

Space station commander Chris Cassidy and Robert Behnken plan to float outside Friday for the first of up to four spacewalks needed to complete the replacement of aging batteries in the lab’s solar power system. NASA managers hope to get the work done in time for Behnken and crewmate Douglas Hurley to return to Earth aboard their Crew Dragon capsule by around Aug. 2, officials said Wednesday.

When the SpaceX capsule blasted off atop a SpaceX Falcon 9 rocket May 30, NASA managers had not specified a return date. But flight controllers now are “looking at landing in the early August timeframe,” Steve Stich, manager of NASA’s Commercial Crew Program, told reporters during a spacewalk preview teleconference.

“The earliest would be around the 2nd of August,” he added. “We’re working those opportunities with the space station program.”

An early August splashdown for the SpaceX capsule would give engineers time to thoroughly evaluate the spacecraft’s first piloted test flight, known as Demo 2, before clearing the decks for an operational, full-duration mission with four astronauts in the mid-September timeframe. That flight is known as the Crew-1 mission.

“Right now, we think we need about six weeks of time to review all the data from the landing and the undocking, and then go through the review process to get to the Crew One launch,” Stich said. “So there’s kind of a six-week iron bar, if you will, between the Demo-2 landing and the Crew-1 launch, and that’s going to be a factor as we look at launch dates later on for Crew-1.”

Since docking at the space station the day after launch, the Crew Dragon has spent most of its time powered down in a sort of electronic hibernation. But flight controllers wake it up every Wednesday to collect engineering data and evaluate its performance. So far, 25 days into its mission, the capsule is performing in near flawless fashion.

One question mark going into the flight was how the spacecraft’s solar cells might be affected by atomic oxygen in the space environment. Engineers expected their performance to degrade over time but as it turns out, the system has been performing above pre-flight predictions.

“The vehicle is doing extremely well,” Stich said. “We’re learning a lot about the vehicle. Nothing that’s of any concern, learning how to manage the systems, the heaters and thermal performance as we go through the changes in the orbit. Also, we’ve been watching the power generation (and) Dragon’s generating more power than we expected.”

SpaceX’s Crew Dragon spacecraft approaches the International Space Station on May 31 with astronauts Doug Hurley and Bob Behnken on-board. Credit: NASA

Hurley and Behnken will end their mission with NASA’s first ocean splashdown since the Apollo-Soyuz mission in 1975. Going into the flight, NASA was focused on landing zones off Cape Canaveral or Jacksonville with a backup site in the Gulf of Mexico near Pensacola.

Stich said mission managers now are evaluating additional sites off Panama City, Tallahassee, Tampa and Daytona Beach to provide more options in the event of stormy tropical weather.

The Crew Dragon carries enough on-board supplies for about three days of flight after leaving the space station. Stich said depending on when the ship actually departs and which landing site is selected, the trip home could be as short as six hours or could stretch to a full day or even longer.

“It looks like the first opportunity to undock and come home would be around Aug. 2,” Stich said. “We’ll just have to sort of see how the EVAs go.”

The space station’s four huge solar wings feed power into eight electrical channels, originally relying on 48 nickel-hydrogen batteries, six per power channel, to supply electricity when the station is not in direct sunlight.

In a multi-year project, spacewalking astronauts have replaced 36 of the 48 older batteries, installing 18 smaller and more efficient lithium-ion powerpacks and circuit-completing adapter plates in their place.

Behnken and Cassidy, who launched to the station April 9 aboard a Russian Soyuz spacecraft, plan two spacewalks, one Friday and the second next Wednesday, to install three of the final six new batteries and adapter plates in power channel 1B and to store the six batteries they will replace. Two more EVAs will be needed to install the final three batteries in channel 3B.

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humanoidhistory: Astronaut Ed White walks in space, June 3,…





















humanoidhistory:

Astronaut Ed White walks in space, June 3, 1965.

(ASU/NASA)