Early on Sunday morning, humankind came one step closer to building a portable habitat for Mars, as an inflatable room was attached to the International Space Station where it will be tested for durability over the next two years. The Bigelow Expandable Activity Module, or BEAM, is a 3,086-pound pod made of layers of fabric and Kevlar-like material that one day might be able to house astronauts during deep-space missions, and possibly even space tourists on sightseeing trips. Developing an expandable space shelter would be a boon to the future of space exploration, says NASA, because this type of structure offers abundant living and working space while being much lighter and more compact than a metal structure. This makes inflatable pods easier to fit onto rockets and cheaper to launch. "When we're traveling to Mars or beyond, astronauts need habitats that are both durable and easy to transport and to set up," NASA wrote in a Tumblr post.