The main task of the day will be completing the transfer of gear and supplies to the station. In the first three days of transfer activities, the crew has moved more than 3,000 pounds of material onto the station.
The third and final reboost maneuver began a few minutes ago at 6:36 p.m. CDT. Like the two previous reboosts, Atlantis' reaction control system jets will be fired 27 times over a 58 minute period to gently raise the station. At the end of tonight's reboost, it is expected that the station's average altitude will have been raised by 27 statue miles.
The astronauts have completed all battery work on the station. The third battery that was replaced has completed its recharging and testing and has been put back online supporting station operations. The fourth and final new battery will begin its recharge later this evening and will be back online before Atlantis undocks tomorrow evening.
Shortly before they begin exiting the station for the final time, Halsell, Horowitz and Weber will take a few minutes to conduct a trio of interviews with three news organizations -- CBS Newspath, Fox News Network and KTBS-TV in Shreveport, LA -- starting at 9:11 p.m. CDT.
Just before 11:30 p.m., Halsell and his crew will reverse the steps they used when they entered the station Monday evening, closing each of the five hatches associated with station components or transfer tunnels. The overall process of closing out the station and preparing for undocking is expected to take about two hours to complete.
Everything remains on schedule for undocking on Friday evening at 6:07 p.m. CDT. Atlantis will perform a one half revolution of the station, before the final separation burn is initiated. Atlantis remains on track for a landing back at Kennedy Space Center at 1:18 a.m. CDT on Monday, May 29th.