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  Things are about to get busy aboard the International Space Station as the first of a series of year-end spacewalks began Tuesday morning.   

  The first spacewalkers and NASA astronauts Josh Cassada and Frank Rubio began their excursion outside the space station at 9:14 am.  ET, with live coverage on NASA’s website.  The event is expected to last approximately seven hours.   

  Cassada wears the red-striped space suit as Extra-Vehicle Crew Member 1, while Rubio is in the unmarked outfit as Extra-Vehicle Crew Member.   

  Astronauts will assemble a support arm on the right side of the space station’s beam.  Hardware to be installed during the spacewalk was delivered to the space station on Nov. 9 aboard a Northrop Grumman Cygnus spacecraft, which safely delivered its cargo despite deploying only one of the two solar arrays after launch.   

  This hardware will allow more solar arrays, called iROSA, to be installed to give the space station a power boost.  The first two installation solar arrays were installed outside the station in June 2021. A total of six iROSAs are planned and will likely boost the space station’s power output by more than 30% once they are all operational.   

  During two more spacewalks on Nov. 28 and Dec. 1, a crew of two astronauts will deploy and install another pair of solar arrays once the mounting hardware is in place.  The solar arrays will be delivered on the next SpaceX Dragon commercial resupply mission, currently scheduled to launch on November 21.   

  Spacewalks are part of the space station crew’s routine as they maintain and upgrade the aging orbiting laboratory, but Tuesday’s spacewalk is NASA’s first since March.  The agency’s spacewalks were halted after European Space Agency astronaut Matthias Maurer ended his first spacewalk with water in his helmet.   

  A thin layer of moisture that exceeded the normal, expected amount was discovered on Maurer’s helmet upon returning to the vent after a nearly seven-hour spacewalk.  Maurer quickly ditched the helmet, in an event deemed “a close call” by NASA, and water samples, suit equipment and the spacesuit itself were returned to Earth for research.  NASA officials determined that the suit showed no material damage.   

  “The cause of the water in the helmet was likely due to the performance of the on-board system, where several variables such as crew effort and crew cooling settings resulted in relatively larger than normal amounts of condensation forming in the system,” according to NASA in a a blog.  after the update.   

  “Based on the findings, the team updated operational procedures and developed new mitigation material to minimize scenarios where integrated performance results in water accumulation, while absorbing any water that occurs.  These measures will help contain any liquid in the helmet to continue to keep the crew safe.”   

  NASA officials gave the go-ahead for spacewalks to continue after the review was completed in October.   

  The research team has developed techniques to manage temperatures in the suit and added new absorption tapes to the helmet, said Dina Kondela, operations integration manager for the International Space Station Program.   

  The thin orange pieces have been placed in various parts of the helmet, which has already been tested in orbit by astronauts inside the space station.   

  “We’ve taken several different models of this and the crew on the boat poured water, basically tried to pour water on the helmet at the same rate that would be kind of the worst, worst case.  And we found that these patches were very, very effective,” Contella said.   

  Tuesday’s spacewalk will allow the crew to test the new pads as they work outside the space station before more complex solar array installation spacewalks within the next two weeks.   

  Meanwhile, a Russian spacewalk is scheduled to take place on Thursday.  Cosmonauts Sergey Prokopyev and Dmitri Petelin will begin their walk at 9 am.  ET to work on the exterior of the Nauka Multipurpose Laboratory Facility.  The duo will prepare a radiator for transport from the Rassvet module to Nauka during their seven-hour spacewalk, which will also be streamed live on NASA’s website.