The connector or ECO sensor system on space shuttle Atlantis' external tank will be installed.

This closeup shows the internal connector to which the replacement feed-through connector in the engine cutoff, or ECO, sensor system on space shuttle Atlantis' external tank will be installed. The feed-through connector passes the wires from the inside of the tank to the outside. Results of a tanking test on Dec. 18 pointed to an open circuit in the feed-through connector wiring, which is located at the base of the tank. The pins in the replacement connector have been precisely soldered to create a connection that allows sensors inside the tank to send signals to the computers onboard Atlantis. The work is being done on Launch Pad 39A. Space shuttle Atlantis is now targeted for launch on Feb. 7. Photo credit: NASA/George Shelton