SUBMITTED BY ARTHUR N1ORC - AMSAT A/C #31468

*Third STS-118 Spacewalk on Tap Today*

Astronauts participate in an educational event with students from Boise, Idaho Image above: Clockwise from left are STS-118 mission specialists Dave Williams, Barbara Morgan and Alvin Drew and Expedition 15 Flight Engineer Clay Anderson. The astronauts participated Tuesday in an educational event with students asking questions from the Discovery Center in Boise, Idaho. Image: NASA TO VIEW IMAGE GO TO:http://www.nasa.gov/mission_pages/shuttle/main/index.html

STS-118 crew members will prepare for future International Space Station assembly when they conduct the mission’s third spacewalk. The excursion, scheduled to begin at 11:01 a.m. EDT(1501 UTC), will be conducted by STS-118 Mission Specialist Rick Mastracchio and Expedition 15 Flight Engineer Clay Anderson.

The spacewalking duo will prepare the Port 6 (P6) truss and its solar arrays for relocation from atop of the station to the end of the Port 5 truss when STS-120 visits later this year. Their tasks include the relocation of an antenna from the P6 to the Port 1 (P1) truss, retrieval a transponder for return to Earth and the relocation of two rail carts on the station’s Integrated Truss Structure. They will install a new transponder on the P1, which along with the relocated antenna will upgrade the station’s communications capability.

Mastracchio and Anderson will also retrieve two material experiments from the station’s exterior. The experiments will be analyzed by scientists on Earth.

Today’s spacewalk will be Mastracchio’s third of the mission. Anderson, who arrived at the station in June, conducted his first spacewalk on July 23 with Expedition 15 Commander Fyodor Yurchikhin.

Mission Specialist Tracy Caldwell will resume her role as STS-118’s spacewalk coordinator and Pilot Charles Hobaugh will be at the controls of the station’s robotic arm.

The spacewalk is slated to last 6.5 hours.

*Mission Management Team Update*

Mission managers have determined that damage to a small section of Endeavour’s heat shield poses no threat to crew safety or mission operations. However, they are discussing options for possible repair work that would ensure preparations on the ground for Endeavour’s next flight will go more smoothly. The damage occurred during the climb to orbit on Aug. 8.

+ View video of tile damage http://www.nasa.gov/mov/186009main_STS118_Site1_Rev2.mov

*Orbiter Thermal Protection System Inspection and Repair Techniques* STS-114 Press Kit excerpt, July 2005 + Identifying and repairing tile damage in flight (444 Kb pdf) http://www.nasa.gov/pdf/186088main_sts114_excerpt_inflight_repair.pdf + Orbiter's Thermal Protection System http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/sts_sys.html#sts-tps + Thermal Protection System Fact sheet http://www-pao.ksc.nasa.gov/kscpao/nasafact/tps.htm + 'How Things Work' Thermal Protection System video http://www-pao.ksc.nasa.gov/kscpao/videos/metafiles/ksc_022805_htw_tps.ram