Space Shuttle Atlantis, Cargo Prepared for March Launch

The overhead sling lowers the orbiter Atlantis next to the external tank and solid rocket boosters stacked on the mobile launcher platform (MLP) below on Feb. 7, 2007. CREDIT: NASA/Amanda Diller.

NASA engineers have attached the shuttle Atlantis to its immense external fuel tank and twin rocket boosters, bringing the spacecraft one step closer to a March launch towards the International Space Station (ISS).

Teams of shuttle workers are going over the multitude of electrical and mechanical connections between the 122-foot (37-meter) orbiter and its 15-story external tank, which stand poised in launch position inside NASA's cavernous Vehicle Assembly Building (VAB) at the Kennedy Space Center (KSC) in Florida [image].

NASA spokesperson George Diller told SPACE.com today that the standard series of engineering checks between Atlantis and its external tank, known as the shuttle interface test, should be complete by Monday. The nearly 100-ton shuttle, which rolled from its maintenance hangar to the VAB on Wednesday [image], is then slated to make the slow trek to NASA's Pad 39A launch site at 7:00 a.m. EST (1200 GMT) on Feb. 14, he added.

Atlantis is due to launch spaceward on March 15 with a six-astronaut crew and a hefty pair of new solar arrays bound for the ISS. Commanded by veteran spaceflyer Rick Sturckow, Atlantis' STS-117 astronauts plan to stage three spacewalks outside the ISS to install the 17.5-ton Starboard 3/Starboard 4 (S3/S4) solar array trusses to right side of the orbital laboratory's metallic backbone.

Built by Boeing, the nearly 45-foot (13-meter) integrated truss segments carry two solar arrays that, when deployed, will have a wingspan of about 240 feet (73 meters). The element is a near mirror-image of the space station's Port 3/Port 4 solar arrays installed by NASA's STS-115 astronaut crew in September 2006 and will balance out the orbital laboratory's current lopsided profile [image].

Boeing spokesperson Susan Wells told SPACE.com that the S3/S4 space station trusses are already packed away in a NASA cargo container, and will be hauled to the space agency's Pad 39A launch site soon to await Atlantis' arrival.

NASA's STS-117 mission is the first of up to five planned shuttle flights to continue ISS construction in 2007.

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