Astronauts install a new solar array outside the International Space Station

NASA astronauts Josh Casada and Frank Rubio stepped out of the International Space Station Saturday for a seven-hour trip into space to install and launch a recently introduced new solar array aboard a SpaceX cargo ship.

Casada and Rubio, both on their first spacewalks, began the spacewalk Saturday at 7:16 a.m. EDT (1216 GMT). The start of the flight was officially marked when the astronauts switched their spacesuits to battery power.

The astronauts moved from Quest in the space station’s airlock to the right side of the lab’s solarbeam, where the station’s robotic arm placed the two ISS Roll-Out Solar Array, or iROSA, modules earlier this week after their launch. space station. The. . SpaceX Dragon cargo box. The Dragon spacecraft delivered the solar arrays to the space station on November 27, along with several tons of supplies and experiments.

The new solar panel blankets were wrapped around the rollers and rolled like a yoga mat once attached to a mounting bracket on the starboard side, Section 4 or S4 of the space station’s electrical truss, which measures more than the length of a football field from end-to-end.

The astronauts first removed one of the two newly delivered iROSA modules from the mount by loosening the screws and loosening the brackets. Cassada placed his foot on the end of the Canadian robotic arm and manually held the coils of the solar array while the arm moved it toward the S4 truss.

The two space pilots placed the iROSA module on a pre-installed mounting bracket during a previous spacewalk. They placed the iROSA unit on its hinge and then installed screws to hold it in place. Casada and Rubio electrical connectors to connect the new iROSA module to the space station’s electrical system. They then laid a Y-cable to feed the power generated from both the new solar panel and the original S4 solar panel to the lab’s power grid.

A stabilizing bracket connects the new arrays to the station’s power channels and rotating joints, which keep the solar wings pointed toward the sun while the spacecraft races around Earth at more than 17,000 miles per hour.

The International Space Station has eight power channels, each powered by electrical power generated by a single solar array that extends from the station’s backbone. The new solar panel, which was deployed on Saturday, will produce electricity for the space station’s 3A power channel.

The original solar panels were launched between 2000 and 2009 during four space shuttle missions. As expected, the efficiency of the station’s original solar panels deteriorated over time. NASA is upgrading the space station’s power system with new solar panels — at a cost of $103 million — that will partially cover six of the space station’s eight original solar panels.

When all six iROSA modules are deployed to the station, the power system will be able to generate 215 kilowatts of electricity to support science operations for at least another ten years. The booster will also accommodate new commercial modules planned for launch on the space station.

The first pair of new solar panels rolled out to the space station last year were installed on the station’s oldest original solar array in the P6 truss section, far left of the front center power strut. Next year, two more iROSA modules will be launched on SpaceX’s resupply mission.

The new solar panels were delivered to NASA by Boeing, Red Wire, and a team of subcontractors.

After integrating the new iROSA module mechanically and electrically into the station’s S4 gearing, the astronauts released clips to hold the solar panel in the launch configuration. This allowed the blankets to gradually expand using the tension energy of the composite trees supporting the solar blanket. The positioning mechanism design eliminates the need for motors to drive the solar panels.

“On the move,” a radio mission control pilot agreed, prompting applause from the support staff in Houston.

“This is unbelievable,” Casada said. “Yeah, it’s really cool,” said Rubio.

The carbon fiber support arms are moved against their natural shape for stowage during launch.

The solar panel took about 10 minutes to deploy to its fully extended configuration, measuring 63 feet long by 20 feet wide (19 by 6 meters). This is about half the length and half the width of the station’s existing solar panels. Despite their small size, each of the new arrays generates roughly the same amount of electricity as each of the station’s existing solar arrays.

Once the blanket was opened, the astronauts adjusted the tie clips to hold the iROSA blanket in place.

The astronauts then went back inside on the space station’s truss to prepare another iROSA module, which will be installed on the left side of the P4 truss section for a spacewalk tentatively scheduled for December 19.

With their tasks complete, Casada and Rubio return to the Quest airlock and seal the hatch. They began recompressing the air chamber at 2:21 p.m. EDT (1921 GMT), completing the spacewalk that lasted 7 hours, 5 minutes.

Saturday’s spacewalk was Casada’s and Rubio’s second career and the 256th spacewalk since 1998 to support assembly and maintenance of the International Space Station.

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