NASA managers are targeting a Feb. 7 launch date for the space shuttle Atlantis as engineers prepare to replace an electrical connector in the spacecraft's external fuel tank.
A decision on the proposed launch target could come as soon as Friday, pending coordination between shuttle and International Space Station (ISS) managers, as well as the agency's international partners, said Candrea Thomas, a spokesperson at NASA's Kennedy Space Center spaceport in Cape Canaveral, Fla.
Meanwhile, shuttle workers are expected to complete efforts to replace a suspect electrical connector on Atlantis' 15-story external tank early Friday, Thomas told SPACE.com.
Atlantis' mission to deliver a new European laboratory to the ISS has been delayed since early December, when fuel tank sensor glitches thwarted two launch attempts. NASA tracked the malfunction to apparent open circuits in an electrical connector used to route sensor wiring from inside the fuel tank to equipment inside Atlantis.
Shuttle managers set a tentative launch target of no earlier than Jan. 24 last week, but added that a slip to early February was likely as engineers continue work on the fuel tank connector.
NASA engineers believe that the super-cold temperatures of Atlantis' liquid hydrogen and liquid oxygen propellant lead to intermittent open circuits between wiring and metal pins inside the electrical connector. They soldered wires directly to their corresponding pins on the new connector to avoid similar glitches in the future, NASA officials said.
The so-called feed-through connector is located low on Atlantis' external tank and is part of a backup system that monitors a shuttle's fuel levels during launch. The engine cutoff system is designed to shut down an orbiter's three main engines before its fuel tank runs dry.
Commanded by veteran shuttle flyer Stephen Frick, the seven astronauts of Atlantis' STS-122 crew will install the European Space Agency's Columbus lab at the ISS during their upcoming spaceflight. The 11-day mission will mark the first of five scheduled shuttle flights of 2008 to continue ISS construction and overhaul the Hubble Space Telescope, NASA has said.