Space station cooling problem to be fixed.

Space station

The international space station needs another space walk to fix the cooling problem. Saturday night the warning alarms awakened the crews in the space station when a circuit breaker tripped, shutting off power to the pump that feeds ammonia to part of the station's cooling system, NASA said in a statement.

"The crew is not in any danger and is monitoring systems and relaxing on an otherwise off-duty day," NASA said.

Engineers are reviewing a preliminary plan for the space walk by 2 crews to replace the failed pump in this week and another walk several days later to complete the fluid and electrical connections.

NASA said the cooling loop shut down around 8 p.m. ET Saturday after monitors detected a power spike in the pump that sends ammonia through the loops. The problem forced other systems on the space station to shut down, NASA said

Earlier, NASA officials warned that there may be some risk to the space station by space debris in last week. On Thursday, NASA said, there are no longer risks.

Without temperature controls, the sun-facing side of the station would have about 121 degrees Celsius and the dark side of the station would have about  -157 degrees Celsius, NASA said.

There are 6 people, 3 Americans and 3 Russians in the space station doing several experiments. NASA said that they are not in danger and they continue their experiments.