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Behnken describes spacewalk views of Crew Dragon as “just awesome”

In this image taken July 1, a spacewalking astronaut snapped a view of the Crew Dragon spacecraft (at right) docked with the International Space Station. Japan’s HTV cargo ship, at bottom in gold, is also seen attached to the space station. Credit: NASA

NASA astronaut Bob Behnken, now in the second half of his mission to the International Space Station aboard SpaceX’s Crew Dragon spaceship, glimpsed the commercial crew capsule from a unique viewpoint at the far end of the station’s solar power truss during a pair of recent spacewalks.

Behnken joined space station Expedition 63 commander Chris Cassidy on two spacewalks June 26 and July 1 to replace aging batteries on the far right side of the research lab’s truss structure, which spans the length of a football field tip-to-tip.

The astronauts got expansive views of the space station from their work site. “Not bad for a view while working,” Behnken tweeted.

In a series of media interviews last week, Behnken said the spacewalks marked the highlight of his mission, at least since he arrived at the International Space Station with crewmate Doug Hurley on the first crewed test flight of SpaceX’s privately-owned Crew Dragon spacecraft.

Behnken and Hurley docked with the space station May 31, a day after launching from the Kennedy Space Center in Florida on top of a SpaceX Falcon 9 rocket. Their historic flight is the first to use a commercial vehicle to carry astronauts into Earth orbit, and the launch was the first time astronauts rocketed into orbit from U.S. soil since the retirement of the space shuttle in 2011.

In response to questions from the Washington Post, Behnken said it was “just awesome to be able to look back and snap a picture” of the Crew Dragon spacecraft during the spacewalks.

This view taken by a spacewalking astronaut July 1 shows SpaceX’s Crew Dragon spacecraft docked with the International Space Station. Credit: NASA

In photos taken from inside the space station, the Crew Dragon is partially obstructed at its docking port on the forward end of the Harmony module. Looking back at the gumdrop-shaped capsule from the edge of the space station’s truss gave the astronauts a different perspective.

The photos also showed Japan’s HTV barrel-shaped cargo freighter berthed on the bottom side of the space station. The HTV stands out in the images because of the golden color of its thermal insulation.

The HTV delivered the six upgraded lithium-ion batteries being installed by Cassidy and Behnken on a series of spacewalks. The two astronauts are gearing up for two more spacewalks later this month, before Behnken and Hurley are scheduled to strap into the Crew Dragon and return to Earth around Aug. 2.

The spacewalks June 26, July 1 and later this month will complete an upgrade of the space station’s power storage system that has stretched over several years. A series of HTV missions have delivered new batteries to the outpost, and astronauts have swapped old nickel-hydrogen batteries for the more capable lithium-ion units, which NASA says will keep the battery system healthy through at least the rest of this decade.

The nickel-hydrogen batteries were launched with the solar power modules on space shuttle missions from 2000 through 2009.

During the June 26 and July 1 spacewalks, Cassidy and Behnken completed work to replace batteries in one of two power channels fed by the solar arrays on the far starboard side of the station’s structural truss. With that complete, seven of the eight solar power channels overall have received new lithium-ion batteries.

The excursions later this month will swap batteries on the eighth and final power channel.

This view taken by a spacewalking astronaut July 1 shows SpaceX’s Crew Dragon spacecraft docked with the International Space Station. Credit: NASA

Behnken told reporters last week that the Crew Dragon spacecraft is performing well more than a month into its mission at the space station. The capsule’s thermal control system is functioning normally, and its computers are weathering the radiation present in low Earth orbit.

“I think that’s the thing that really gives Doug (Hurley) and I continued confidence in the vehicle is that it is matching the engineering predictions for all of those things,” Behnken said.

Future Crew Dragon missions will last up to seven months, and NASA has approved the Crew Dragon test flight, designated Demo-2, to remain in orbit for up to four months. But NASA officials plan to bring Hurley and Behnken back to Earth around Aug. 2, starting a series of data and certification reviews expected to last around six weeks before the deeming the Crew Dragon ready for operational crew rotation flights to the space station.

Three NASA astronauts and a Japanese astronaut are assigned to the first operational Crew Dragon mission, which is expected to launch from the Kennedy Space Center as soon as mid-September.

More photos from the June 26 and July 1 spacewalks are posted below.

NASA astronaut Bob Behnken is pictured outside the International Space Station on a spacewalk June 26. Credit: NASA
NASA astronaut Bob Behnken works outside the space station during a June 26 spacewalk. Credit: NASA
Backdropped by a space station solar array, NASA astronaut Bob Behnken works on the station truss in a July 1 spacewalk. Credit: NASA
NASA astronaut Chris Cassidy is seen inside the space station’s Quest airlock during a July 1 spacewalk. Credit: NASA
NASA astronaut Bob Behnken outside the space station on a July 1 spacewalk. Credit: NASA

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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.