The astronauts from the ISS and the Endeavour are now collecting as many recycled urine samples as possible from a machine that they coaxed into operation recently. The device for turning urine into drinking water seemed to be working fine Tuesday, after several days of tinkering by the astronauts. Space Station commander Mike Fincke told Mission Control early Tuesday morning that they have successfully tested the device. Another test was planned overnight, while the seven astronauts on Endeavour and three space station crew members slept. In order to deal with this problem, NASA added a 16th day to Endeavour’s mission, so astronauts could tinker with the urine processor before the shuttle returned to Earth. If none of the tests would have been successful, the damaged pieces of the device would have been brought home by Endeavour.

The urine processor makes up a section of the $154 million water recycling system that was delivered to the space station by Endeavour. Samples of the processed urine, sweat and condensation will be tested on Earth before astronauts can start drinking the purified water next year. Astronaut Donald Pettit, who worked on the urine processor, said it’s normal to have a few hiccups with the new equipment, which was delivered along with others in order to make the station be habitable for three more people. Furthermore, NASA was also happy with the way a newly repaired rotary joint was working. The joint, which was needed to point the solar wings on the right side of the space station toward the sun, appeared to operate fine during a three-hour test on Tuesday. The joint has been jammed for over a year and Endeavour’s astronauts spent four spacewalks cleaning and lubing it, installing new bearings. The Endeavour is set to undock Friday and land in Florida on Sunday.