GALEX Status Update

December 20, 2007

GALEX Craft

The process to restore the far-ultraviolet detector on the Galaxy Evolution Explorer has been successfully completed, and the instrument resumed full, normal operations on December 17.

The detector experienced an overcurrent condition on Nov. 17, and was shut off by the instrument's on-board fault protection.

Project team members concluded the far-ultraviolet detector exhibited a "slow" overcurrent condition, like that which occurred in early 2006. The cause was a short within the detector's microchannel plate stack. The project used the same recovery technique established in the 2006 recovery. This involved "hi-potting," or cycling the detector on and off at progressively higher voltage.

The onboard near-ultraviolet detector has continued to operate normally.