After the delay, NASA astronauts went for a walk in space to replace the defective antenna of the space station

Two NASA astronauts were due to embark on a spacewalk on Thursday to replace a defective antenna on the International Space Station (ISS) after a 48-hour delay caused by an orbital debris alert, which was later found to be of no concern. .

NASA TV has planned a 6-and-a-half-hour spacewalk live coverage, scheduled to begin at 7:10 a.m. Eastern time (1210 GMT), when astronauts Thomas Marshburn and Kayla Barron emerge from an orbiting laboratory lock. , about 250 miles (402 km) above the Earth. Exit is the fifth spacewalk for Marshburn, 61, a doctor and former flight surgeon with two previous orbits, and the first for Barron, 34, a U.S. Navy submarine officer and engineer. nuclear at its space launch for NASA.

Their goal is to remove a defective S-band radio antenna assembly that is now more than 20 years old, and replace it with a spare assembly stored outside the space station. The space station is equipped with other antennas that can perform the same functions, but the installation of a replacement system ensures an ideal level of communications redundancy, NASA said.

Marshburn will work with Barron as he is positioned at the end of a robotic arm maneuvered inside by German astronaut Matthias Maurer of the European Space Agency, with the help of NASA crew colleague Raja Chari. The four arrived at the space station on November 11 in a SpaceX Crew Dragon capsule launched from the Kennedy Space Center in Florida, joining two Russian cosmonauts and a NASA astronaut, Mark Vande Hey, already aboard the orbiting outpost.

Four days later, an anti-satellite missile test conducted without warning by Russia generated a field of debris in low Earth orbit, forcing the seven members of the ISS crew to take refuge in their docked spacecraft to allow a rapid escape until the immediate danger passed, NASA said. The residual cloud of debris from the exploded satellite has since dissipated, according to Dana Weigel, NASA’s deputy director of the ISS program.

However, NASA estimates that the remaining fragments continue to present a “slightly increased” background risk for the space station as a whole and a 7% higher risk of piercing the suits of space travelers, compared to before the Russian missile test. Weigel told reporters Monday. However, NASA determined that these levels of risk, although increased, were within tolerable limits and continued with preparations to conduct the spacewalk as originally planned on Tuesday.

A few hours before the operation began, NASA received an alert from US military space tracking instruments warning of a newly detected debris collision threat, prompting mission control to delay the extra-vehicle mission. (EVA). On Tuesday afternoon, NASA said its assessment concluded that the wreckage in question – its origin unclear – posed no risk to space travel or the station, and the antenna replacement was rescheduled for Thursday morning.

Thursday’s exercise marks the 245th spacewalk to support the assembly and maintenance of the space station, which this month has surpassed 21 years of continuous human presence, NASA said. A NASA spokesman, Gary Jordan, said the postponement of this week’s spacewalk was considered the station’s first ever caused by a rubble alert.

(This story was not edited by Devdiscourse staff and is automatically generated from a syndicated feed.)