Jerry Ross and Jim Newman began the second of three planned space walks for the STS-88 mission at 2:33 p.m. Central time Wednesday, and immediately set out to install two boxy antennas on the side of the Unity module that will enable U.S. flight controllers to monitor that component's systems and provide basic videoconferencing for the first permanent occupants of the station in January 2000. The so-called "early" S-band communications system will be completed later today when the astronauts install hardware inside Unity. The system will provide more capability to retrieve data and telemetry from Unity, which otherwise would be available only as the new International Space Station passed over Russian ground stations.
Ross and Newman pressed ahead with the removal of launch restraint pins on the four hatchways on the body of Unity to which additional station modules and truss structures will be mated on future assembly missions. The two space walkers also installed a sunshade over Unity's two data relay boxes to ensure that they will be protected against harsh sunlight as the station circles the Earth.
Near the end of the space walk, Newman was hoisted to the Zarya control module on the end of Endeavour's robot arm so that he could use a grappling hook to free a backup rendezvous system antenna. After nudging the antenna with the grappling device, the pole popped out to its fully extended position as the shuttle passed over the northeast coast of Australia. The astronauts will attempt to free a duplicate antenna that is jammed on the other side of Zarya during their final space walk Saturday.
Ross and Newman returned to Endeavour's external airlock and began to repressurize it at 9:35 p.m., completing a 7 hour, 2 minute excursion. So far, they have worked outside Endeavour a total of 14 hours and 23 minutes. This was the third space walk for Newman and the sixth for Ross, who now has spent 37 hours, 10 minutes in the void of space -- a U.S. record.
Later today, the astronauts will enter the International Space Station for the first time as they open hatches to Unity and Zarya. If all goes as planned, the astronauts will climb aboard Unity around 1:15 p.m. Central time to complete installation of the S-band communication system in the U.S. component, and float into Zarya about an hour and a half later to unstow hardware that will be used by visiting astronauts on future assembly missions.
After arriving in Zarya, cosmonaut Sergei Krikalev will install a new battery charging unit in the Russian module. One of Zarya's six batteries has experienced a problem discharging stored energy in its automatic configuration. Krikalev has swapped out an identical component during two previous flights on the Russian Space Station Mir.
The astronauts will begin an eight-hour sleep period at 2:36 a.m. Central time and be awakened at 10:36 a.m. to begin their eighth day of work in orbit.
Endeavour and the International Space Station are flying at an altitude of 248 statute miles with all of their systems in excellent shape.