Yesterday, Tuesday, June 12, 2007, the seven-person STS-117 Shuttle crew and the three-person Space Station Expedition 15 crew heard a fire alarm go off in the Russian section of the Station. However, the problem was determined to be a computer glitch between U.S. and Russian computers--after smoke and fire were not seen or smelled.

To add to the perplexing situation, a Russian computer failed, which transferred attitudinal control of the Space Station to the Shuttle’s maneuvering jets. Power levels dropped because of this condition and nonessential equipment were forced to be turned off temporarily to conserve power.

U.S. astronauts Pat Forrester and Steve Swanson will be in charge today for the second of four spacewalks scheduled onboard the Space Station. This second walk is scheduled to start at 2:03 p.m. EDT 18:03 GMT) and last about 6.5 hours. Television coverage is planned on the NASA channel, and Internet coverage is provided at NASA TV.

Ground controllers at the Johnson Space Center had already started retracting the P6 array by remote control—that activity, which involved the first panel, began at 6:47 a.m. Wednesday morning. Astronauts inside the Space Station took over the retraction process later in the day. The old array is being removed so the new solar array will be better able to maintain its position with the Sun.

After the 31 sections of the old array are completely retracted (which is expected to occur on Thursday), astronauts—during a later spacewalk—will move the array to the Port 5 truss. During the spacewalk of Forrester and Swanson, if trouble occurs during the retraction, they will be available to help with special tools used to push the seconds in place.

However, Forester’s and Swanson’s primary duty on Wednesday will be to remove the remaining restraints and locks from the Solar Alpha Rotary Joint (SARJ) on the Starboard 3/Starboard 4 (S3/S4) truss segment.

Yesterday, the two new solar arrays were successfully extended automatically to their full length, each with a length of 115 feet (35 meters). The two arrays will provide about 20 kilowatts of power to the Space Station. In all, the entire wingspan of the two arrays is over 240 feet (73 meters). This latest edition to the Station’s solar arrays is the third one to be installed.

While these two spacewalking astronauts are outside of the Space Station, U.S. astronaut Jim Reilly, one of the STS-117 crewmembers, will be coordinating the spacewalk, and U.S. astronaut Lee Archambault, the pilot for Atlantis, will be operating the robotic arm on the Station.

The members of the STS-117 Mission Management Team, headed by John Shannon, are still researching how to fix the peeled-back 24-square-inch gap in the thermal blanket on top of one of the Shuttle’s OMS engine pods, which are located near the tail of Atlantis. They are currently researching the possibility of using a sewing kit that was originally developed to repair spacesuits. The sewing kit consists of stainless steel wire and a needle-like instrument. Other methods of repair, such as using adhesive or wire ties, are also being considered.

It has not been decided, yet, which spacewalk will take care of the repair job on the thermal blanket.

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