A U.S. astronaut and his Russian crewmate were set to venture outside the international space station Thursday for a strenuous six-hour spacewalk intended to fix a faulty antenna, The Associated Press reported. The main mission of Michael Lopez-Alegria and Mikhail Tyurin is to fold an antenna on a Russian Progress cargo ship that could be an obstacle when the vessel needs to be undocked to make room for a new space ferry, said Russian Mission Control spokesman Valery Lyndin. The spacewalk will be the 10th for Lopez-Alegria, who set a U.S. record for total time walking in space _ 61 hours and 22 minutes _ when he and fellow American Sunita Williams did maintenance work outside the space station earlier this month. Astronaut Jerry Ross, who has made nine space walks, held the previous U.S. time record, while Russian cosmonaut Anatoly Solovyov holds the world mark with more than 82 hours. Lopez-Alegria and Tyurin were expected to spend most of their time outside the station trying to free the cargo ship's antenna, which got stuck in a railing on the station during its docking in October, Lyndin said. Williams will stay on the station, monitoring their movement and maintaining contact with Mission Control in Korolyov, outside Moscow. The Progress M-58 spacecraft docked smoothly with the station in October, but the faulty antenna prevented it from mooring completely for several tense hours. The crew were unable to free the antenna during a previous spacewalk. «If they again fail to fold the antenna, they have special scissors to cut it so that it poses no obstacle to undocking the ship,» Lyndin told The Associated Press. Progress cargo ships regularly ferry supplies to the international space station. Shortly before a new cargo ship is launched, the old one _ filled with garbage _ is removed and dumped in the ocean to free the station's docking port.