After taking Christmas Day off, commander Mike Lopez-Alegria and flight engineers Mikhail Tyurin and Sunita Williams began unpacking, inventorying and stowing the equipment and supplies brought to the ISS by Discovery, NASA officials in Houston said.

The crew entered the new supplies and equipment in the Inventory Management System, a computerized, bar-coded tool that keeps track of the material aboard the orbiting lab.

During the week, crew members also worked on experiments that analyze heart function during space flights of long duration, measured cosmic rays, and examined plant growth and changes in blood of long-duration space travelers.