IF AN ASTRONAUT WEIGHS 180 POUNDS ON EARTH WHAT WOULD BE HIS WEIGHT IN OUTER SPACE?

A pound is a unit of mass. Mass is constant throughout the cosmos, so if the astronaut has a MASS of 180 pounds on Earth, it will be the same even in space. But, the astronaut doesn't have a weight of 180 pounds. His MASS is 180 pounds. Weight = mass x gravity. So, in space, his weight is 0 Newtons.