NASA astronauts Josh Cassada and Frank Rubio headed exterior the Worldwide Area Station Saturday for a seven-hour spacewalk to put in and unfurl a brand new roll-out photo voltaic array just lately delivered by a SpaceX cargo ship.
Cassada and Rubio, each on their first flights to area, started the spacewalk at 7:16 a.m. EST (1216 GMT) Saturday. The beginning of the tour was formally marked when the astronauts switched their spacesuits to battery energy.
The astronauts moved from the area station’s Quest airlock to the starboard, or proper, aspect of the lab’s solar energy truss, the place the station’s robotic arm positioned two new ISS Roll-Out Photo voltaic Array, or iROSA, models earlier this week after extracting them from the trunk of a SpaceX Dragon cargo capsule. The Dragon spacecraft delivered the photo voltaic arrays to the area station Nov. 27, together with a number of tons of provides and experiments.
The brand new photo voltaic array blankets have been wrapped round spools and unrolled like a yoga mat as soon as put in onto a mounting bracket on the starboard 4, or S4, part of the area station’s energy truss, which measures greater than the size of a soccer subject from end-to-end.
The astronauts initially labored to take away one of many two newly-delivered iROSA models from its service by releasing bolts and launch restraints. Cassada took place on a foot restraint on the tip of the Canadian-built robotic arm, and held the photo voltaic array spools by hand whereas the arm moved him to the S4 truss.
The 2 spacewalkers positioned the iROSA unit onto a mounting bracket pre-positioned throughout a earlier spacewalk. They unfolded the iROSA unit on its hinge, then put in bolts to safe it into place. Cassada and Rubio mated electrical connectors to hyperlink the brand new iROSA unit to the area station’s electrical system. Then they put in a Y cable to route energy generated by each the brand new roll-out photo voltaic array and the unique S4 photo voltaic panel into the lab’s energy grid.
The mounting bracket plugs the brand new arrays into the station’s energy channels and rotary joints, which hold the photo voltaic wings pointed on the solar because the spacecraft races round Earth at greater than 17,000 mph.
The Worldwide Area Station has eight energy channels, every fed with electrical energy generated from one photo voltaic array wing extending from the station’s truss spine. The brand new photo voltaic array deployed Saturday will produce electrical energy for the area station’s 3A energy channel.
The unique photo voltaic panels launched on 4 area shuttle missions from 2000 to 2009. As anticipated, the effectivity of the station’s authentic photo voltaic arrays has degraded over time. NASA is upgrading the area station’s energy system with the brand new roll-out photo voltaic arrays — at a value of $103 million — which can partially cowl six of the station’s eight authentic photo voltaic panels.
When all six iROSA models are deployed on the station, the ability system will likely be able to producing 215 kilowatts of electrical energy to help no less than one other decade of science operations. The enhancement will even accommodate new industrial modules deliberate to launch to the area station.
The primary pair of latest roll-out photo voltaic arrays launched to the area station final 12 months, and have been put in over the station’s oldest set of authentic photo voltaic panels on the P6 truss part, positioned on the far left finish of the outpost’s energy truss. Two extra iROSA models are slated to launch on a SpaceX resupply mission subsequent 12 months.
The brand new photo voltaic arrays have been equipped to NASA by Boeing, Redwire, and a staff of subcontractors.
As soon as the brand new iROSA unit was mechanical and electrically built-in onto the station’s S4 truss, the astronauts launched clamps conserving the roll-out photo voltaic array spooled in its launch configuration. That allowed the blankets to step by step unroll utilizing pressure vitality within the composite booms supporting the photo voltaic blanket. The design of the deployment mechanism eliminates the necessity for motors to drive the photo voltaic array.
“It’s beginning to transfer,” one of many astronauts radioed mission management, prompting applause among the many help staff in Houston.
“That’s unimaginable,” Cassada mentioned. “Yeah, it’s fairly cool,” Rubio chimed in.
The carbon fiber help booms have been rolled again towards their pure form for storage throughout launch.
It took about 10 minutes for the photo voltaic array to unroll to its totally prolonged configuration, stretching about 63 ft lengthy and 20 ft vast (19-by-6 meters). That’s about half the size and half the width of the station’s present photo voltaic arrays. Regardless of their smaller measurement, every of the brand new arrays generate about the identical quantity of electrical energy as every of the station’s present photo voltaic panels.
As soon as the blanket unfurled, the astronauts adjusted tensioning bolts to safe the iROSA blanket in place.
Then the astronauts headed again in-board on the area station’s truss to prep one other iROSA unit, which will likely be put in on the left-side P4 truss part on a spacewalk tentatively scheduled for Dec. 19.
With their duties full, Cassada and Rubio made their method again to the Quest airlock and closed the hatch. They began repressurizing the airlolk compartment at 2:21 p.m. EST (1921 GMT), finishing the 7-hour, 5-minute spacewalk.
The spacewalk Saturday was the second within the careers of Cassada and Rubio, and the 256th spacewalk since 1998 in help of Worldwide Area Station meeting and upkeep.
E mail the writer.
Comply with Stephen Clark on Twitter: @StephenClark1.