GALEX Status Update

August 21, 2009


Engineers and scientists are continuing to work on the recovery of the far-ultraviolet instrument on NASA's Galaxy Evolution Explorer. On May 29, the instrument experienced an overcurrent condition (too much current) and shut down. The project reviewed data from the incident and confirmed it had the same characteristics as three previous incidents occurring in 2005, 2006 and 2007.

The project is performing a series of actions to remove debris material believed to be causing the shorting condition from within the detector. The actions require multiple on-and-off cycling of the detector at various voltage levels, followed by an analysis of the results. The voltage and current settings are then adjusted, and the process is repeated. The project is looking for the optimum voltage level that produces a desired change in the detector current characteristics. This careful process takes time. Once that point. or voltage level, is determined, the detector will be operated at that level for extended time periods to facilitate removal of the material.

The Galaxy Evolution Explorer's near-ultraviolet detector is working properly and is currently making science observations. The project plans to make up for lost observations with the far-ultraviolet detector when it resumes operations.