An unexpected circuit breaker trip early Sunday caused a power outage on the International Space Station. All systems were back up by Monday morning with no impact to operations on board. The safety of the Expedition 14 crew and the complex was never an issue.
The first indications of a problem came with the loss of communications between the station and mission control just after 12:00 a.m. CST Sunday when an electrical switching unit experienced a brief malfunction that appropriately caused a breaker to trip, protecting the electrical system of the station much like a circuit breaker protects electrical systems and equipment in a home.
Expedition 14 Commander Mike Lopez-Alegria and Flight Engineers Mikhail Tyurin and Suni Williams – awake since mid-evening Saturday – took immediate action and followed procedures on board to recover the communications link with mission control, Houston, at about 1:35 a.m.
During the remainder of Sunday and through early Monday, restoration of systems continued. The systems affected included:
– One of two redundant communications systems
– One of four gyroscopes used to maintain the station's position, or orientation
– Several scientific facilities, including the freezer containing experiment samples
– The Ku Band high data rate and television system
