07/01/2020 Science 0

NASA astronauts Chris Cassidy and Robert Behnken were once again outside the International Space Station (ISS) Wednesday on the second of two scheduled space walks to upgrade the station’s batteries.The astronauts began the project Friday, a spacewalk that was only notable because Cassidy lost a small mirror that was attached to his suit by the wrist. In an interview with the Associated Press Tuesday, Cassidy called losing the mirror “a real bummer” and couldn’t figure out how it happened. He said he just glanced down and saw it disappear into the darkness.The astronauts were also asked about the COVID-19 pandemic on earth, which they are closely watching. Both astronauts are based in Houston, where virus cases have seen a surge.  Likewise, in Florida, home of the Kennedy Space Center, the launch site for the SpaceX spacecraft that brought Behnken to the ISS a month ago.Florida and Texas each have had to reimpose restrictions in response to the surges. Both astronauts had to be quarantined for several days before they left for the ISS and really did not experience any of the restriction’s others had to face, but both said they are greatly concerned about the situation on earth.Wednesday, the two are working on removing the sixth nickel-hydrogen battery outside the space station and replace it with a new lithium-ion battery and an adapter plate. The swap will upgrade the station’s power supply by replacing the batteries that store power generated by the station’s solar arrays and provide it to the microgravity laboratory when the station is not in sunlight as it circles Earth during orbital night. 
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