STS-88 Day 4 Highlights

Back to STS-88 Flight Day 03 Highlights:

On Sunday, December 6, 1998, 11:00 a.m. CST, STS-88 MCC Status Report # 8 reports:

Endeavour's crew awoke at 10:36 a.m. CST today to begin the orbital assembly of the International Space Station, uniting the first two station modules, Zarya and Unity. The astronauts were awakened to the sounds of "Somewhere Over the Rainbow," requested by Commander Bob Cabana's daughter, Sarah.

Endeavour's crew will begin the final stages of a rendezvous with the Zarya module with an engine firing planned at about 1:30 p.m. CST, when Endeavour is at a point about 55 statute miles behind Zarya. That burn will slow the rate at which the shuttle is closing on the module. The final phase of the rendezvous will begin at about 3:15 p.m. CST, when Endeavour performs a terminal phase initiation engine firing, or TI burn, at a point about 9 statute miles behind Zarya. The TI burn will place Endeavour on a path to arrive about 600 feet directly below Zarya on its next orbit of the Earth. With the three-story-high Unity connecting module latched upright in the shuttle's payload bay, Cabana will take manual control of the shuttle at about 4:45 p.m. CST as it moves to within about a half-mile of Zarya. Cabana and Pilot Rick Sturckow will execute a sequence of maneuvers that will bring Endeavour from 600 feet below Zarya along a circular path, passing about 350 feet in front of it! and finally reaching a point about 250 feet directly above the module.

From there, Cabana will fly Endeavour down toward the Zarya, relying on views from television cameras in the shuttle's payload bay to align the module, since Unity obstructs the view out of the cockpit windows. Mission Specialist Nancy Currie will operate Endeavour's outstretched arm for the capture of Zarya. Mission Specialists Jim Newman and Sergei Krikalev will assist with the rendezvous, using a hand-held laser to provide range and closing rate information as Endeavour narrows the gap with Zarya.

When the edge of Endeavour's payload bay is within 10 feet of Zarya, Currie will use the robotic arm to capture the module, about 5:46 p.m. CST. She then will maneuver it into a position precisely aligned above Unity's docking mechanism. The 21-ton Zarya will be the most massive object ever moved with the robotic arm, more than three tons heavier than the Compton Gamma Ray Observatory that was released using the arm on Space Shuttle mission STS-37.

Once the Zarya and Unity docking mechanisms are aligned and positioned only inches apart, Currie will put the arm into a "limp" mode while Cabana fires Endeavour's thrusters to force the mechanisms together, about 7:36 p.m. CST.

Zarya is 41.2 feet long and 13.5 feet wide at its widest point. Once attached to Unity, the new station will tower about 76 feet above Endeavour's payload bay and have a solar array span of about 78 feet and a combined mass of approximately 80,000 pounds. When fully assembled in 2004, the International Space Station will be larger than a football field and have a mass of more than one million pounds.

Following the mating of Unity with Zarya, Sturckow and Mission Specialist Jerry Ross will begin early preparations for the crew's entry into the new station, planned for Thursday, and begin setting up equipment for tomorrow's planned spacewalk by Ross and Newman to connect power and data cables between Unity and Zarya.

On Monday, December 7, 1998, 3:00 a.m. CST, STS-88 MCC Status Report # 9 reports:

Endeavour's astronauts continued the assembly of the International Space Station late Sunday, mating the Russian-built Zarya control module with the U.S.-built Unity connecting module in the shuttle's cargo bay following a flawless rendezvous and grapple of Zarya.

Using the shuttle's 50-foot-long robot arm, astronaut Nancy Currie plucked Zarya out of orbit at 5:47 p.m. Central time Sunday, more than 16 days after it was launched on a Russian Proton rocket from the Baikonur Cosmodrome in Kazakstan as the first component of the new station. After slowly and carefully aligning Zarya's docking mechanism with a comparable mechanism on Unity's Pressurized Mating Adapter-1, Commander Bob Cabana fired Endeavour's downward jets at 8:07 p.m. to drive the two large modules together.

Initial attempts to firmly latch Zarya and Unity together while the shuttle's robot arm was attached to Zarya's grapple fixture were unsuccessful. But after Currie ungrappled the module, hooks and latches between Zarya and Unity engaged at 8:48 p.m., forming a tightly sealed, 35-ton, 76-foot-tall structure rising from Endeavour's payload bay, the size of a seven-story building.

Currie used the robot arm cameras to conduct a detailed survey of Zarya, focusing on two antennas belonging to the Telerobtically Operated Rendezvous System (TORU), which failed to deploy following launch on Nov. 20. Flight controllers concluded that the pyrotechnic pins holding the antennas in place actually fired, but the antennas did not unfurl as planned. The antennas, which are part of a backup navigational aid system, are emitting signal strength in their current position and pose no problem for future station operations. But flight controllers are considering having astronaut Jerry Ross conduct a more thorough survey of the antennas while affixed to the end of the shuttle's robot arm during the first space walk he and Jim Newman will conduct Monday night. Mission managers have not decided whether Ross and Newman will be called upon to manually deploy the antennas on a future space walk.

The first space walk, scheduled to begin about 4:30 p.m. Central time today, may begin earlier if Ross and Newman are ready to depressurize Endeavour's external airlock ahead of schedule. During the planned 6 =-hour excursion, Ross and Newman will hook up electrical cables and connectors between Zarya and Unity, enabling power to flow into the U.S. component for the first time. That will allow Unity's avionics, computers and heaters to be activated to set the stage for the ultimate shifting of command and control and the origination of the power for the International Space Station from the Russian components to the U.S components once the American-built Destiny laboratory is joined to the station in February 2000.

Russian and American flight controllers also are continuing discussions on the possible swap out of a suspect component for one of Zarya's six batteries. The battery is not discharging properly in its automatic mode. A replacement unit is available for installation if mission managers approve the plan. The battery is operational and poses no threat to future station operations even if left in its current configuration. The astronauts are scheduled to begin an eight-hour sleep period at 3:36 a.m. Central time and will be awakened at 11:36 a.m. to prepare for the first space walk of the flight.

Endeavour and the International Space Station are orbiting the Earth at an altitude of 240 statute miles with all systems in excellent shape.

Go to STS-88 Flight Day 5 Highlights: