NASA plans to launch space shuttle Discovery on Tuesday, though engineers have not nailed down the cause of the problem that forced the space agency to abandon last week"s attempt. Discovery was less than three hours from liftoff July 13 when officials halted the countdown because of a balky fuel gauge.
After a week of troubleshooting, engineers have suspicions but no certainty. They think one possible explanation might lie with electrical signals from some of the equipment on the shuttle, said John Muratore, shuttle systems engineering manager. Those signals could be interfering with the power supply to the fuel gauges. Tests examining that possibility were likely to continue into today. NASA would like to launch Discovery by July 31. That date is driven by the need for lighting conditions that allow the shuttle to be photographed clearly so it can be checked for damage.