ESA astronaut Hans Schlegel was fully fit to launch with Columbus on 7 February. However, a condition developed that is not life- or mission-threatening in any way, but that could affect his efficiency during a spacewalk.
As the transfer of Columbus to the ISS is of greatest importance, following a private medical conference with the crew, ISS and STS mission management made the decision to delay EVA1 by one day and to have Stanley Love take the place of Hans, to achieve maximum chance of operational success.
Hans will act as the EVA internal coordinator during this spacewalk. The situation will be monitored in order to make decisions for the later mission EVAs. ESA will continue to be fully involved in this process.
The mission's first spacewalk is scheduled to begin at 15:35 CET on Monday. The installation of Columbus is set for 22:25 CET.