nasa spacewalk postponed.

NASA says it has canceled the year’s first spacewalk and may bring its crew back early from the International Space Station due to a medical issue. The spacewalk was supposed to happen Thursday, but was postponed because of an unspecified medical concern with an astronaut, who was not identified. The space agency says the crew member is stable and is considering options including an early end to the mission. The latest crew has been on the space station since August after launching from Florida.