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The International Space Station is set to receive its second solar power boost in a month during a spacewalk on Thursday. The event comes after a piece of wayward space garbage interfered with plans to carry out the spacewalk Wednesday.
NASA was forced to implement a 24-hour delay so that the space station could fire up its thrusters to move out of the way of the debris, which was identified as a fragment of an old Russian rocket. Near-collisions in space are common, as low-Earth orbit — the area in which the ISS orbits — is becoming increasingly congested with satellites and space junk.
“The crew is not in any immediate danger,” NASA noted in a blog post Wednesday.
The spacewalk kicked off Thursday around 8:30 a.m. ET and is expected to last for about seven hours. Live coverage began at 7 a.m. ET on NASA’s website.
NASA astronauts Josh Cassada and Frank Rubio are working to install a solar array outside the floating laboratory. Rubio is serving as extravehicular crew member 1 and is wearing a suit with red stripes, while Cassada is wearing an unmarked white suit as extravehicular crew member 2.
Thursday’s spacewalk is one of many intended to install rollout solar arrays, called iROSAs, to increase electrical power on the space station.
The first two rollout solar arrays were installed outside the station in June 2021. The plan is to add six iROSAs, which will likely boost the space station’s power generation by more than 30% once all are operational.
Two more arrays were delivered to the space station on November 27 aboard the 26th SpaceX Dragon commercial resupply mission, which also carried dwarf tomato seeds and other experiments to the orbiting laboratory. Rolled up like carpet, the arrays weigh 750 pounds (340 kilograms) each and are 10 feet (3 meters) wide.
Cassada and Rubio already installed one outside the space station during a spacewalk on December 3.
During Thursday’s spacewalk, the two will install a solar array to increase capacity in one of the space station’s eight power channels, located on its port truss.
Once the array is unfurled and bolted into place, it will be about 63 feet (19 meters) long and 20 feet (6 meters) wide.
The original solar arrays on the space station are still functioning, but they have been supplying power for more than 20 years and are showing signs of wear after long-term exposure to the space environment. The arrays were originally designed to last 15 years.
Erosion can be caused by thruster plumes, which come from both the station’s thrusters and those of the crew and cargo vehicles that come and go from the station, as well as micrometeorite debris.
The new solar arrays are being placed in front of the original ones….