The International Space Station is featured in this image photographed by an STS-134 crew member on the space shuttle Endeavour after the station and shuttle began their post-undocking relative separation on May 29, 2011.
HOUSTON – The space shuttle Atlantis is poised to arrive at the International Space Station today (July 10), in what will be the very last time that a shuttle docks to the massive orbiting outpost.
Atlantis launched from NASA's Kennedy Space Center on Friday (July 8) to begin a two-day chase of the space station in orbit. The shuttle and its four-person crew are expected to link up with the station at 11:07 a.m. EDT (1507 GMT) today.
Atlantis' STS-135 mission is the last ever flight of NASA's space shuttle program and today's docking will mark the final time that an orbiter parks at the complex. [Photos of NASA's Last Space Shuttle Launch]
The agency is ending its 30-year space shuttle program to focus on space exploration to destinations deeper in space, such as an asteroid or Mars. As with the two other orbiters in NASA's shuttle fleet, Atlantis will be retired for good following the end of its STS-135 flight.
Atlantis' final visit
Commander Chris Ferguson, pilot Doug Hurley, and mission specialists Sandra Magnus and Rex Walheim are flying a 12-day mission to the space station to deliver critical supplies and equipment.
The astronauts will join the six spaceflyers who are currently living aboard the station: Russian cosmonauts Andrey Borisenko, Alexander Samokutyaev and Sergei Volkov, NASA astronauts Mike Fossum and Ron Garan, and Japanese astronaut Satoshi Furukawa.
The shuttle astronauts began their day at 3:29 a.m. EDT (0729 GMT) to make final preparations for their scheduled docking with the space station. Mission Control roused the crew with the song "Mr. Blue Sky" by the Electric Light Orchestra, a wakeup tune picked for Ferguson by his family. [10 Amazing Space Shuttle Photos]
"Another great day to be in space," Ferguson said as he thanked his wife Sandy and children. "Our families all face special challenges right around mission time, and Sandy you've always handled it with poise and grace."
Atlantis will perform a series of engine burns over the next few hours to place the shuttle in position to park at the orbiting laboratory.
As part of the standard pre-docking activities, the astronauts will guide Atlantis through a slow back flip beneath the space station so astronauts aboard the orbiting lab can snap high-resolution photos of the shuttle's heat shield.
The maneuver, called a Rotational Pitch Maneuver (RPM), is scheduled to begin at around 10:06 a.m. EDT (1406 GMT). This back flip is one of three separate heat shield inspections that are built into every shuttle mission.
With only four astronauts onboard Atlantis, as opposed to a larger crew of six or seven, Ferguson, Hurley, Magnus and Walheim will have their hands full during the shuttle's rendezvous and docking. Ground teams here in Mission Control at NASA's Johnson Space Center have trained to provide support the small crew, and are prepared to change some procedures to accommodate the fewer astronauts onboard.
"For the various other ancillary things that are not directly related to actually, physically flying the bird, those things we've got fewer hands and fewer minds available to really give attention to those things," said shuttle flight director Kwatsi Alibaruho. "We just have to be more judicious about how we manage those systems so that we can delay those calls when appropriate and get them in when we've got the opportunity."
Returning to the space station
Each member of Atlantis' veteran crew has visited the space station before on previous shuttle flights, and Magnus completed a long-duration stint at the outpost in 2008.
The astronauts spoke about being anxious to see the space station again, and to experience how the complex has changed since their last visits. [Most Memorable Space Shuttle Missions]
"I want the million-dollar view out of the Cupola, that’s what I want to see," Ferguson said in a preflight interview. "When I was up there last Node 3 wasn’t there, the Cupola was not there, the PMM [permanent multi-purpose module] was not there, station has expanded in a lot of great ways, but of course that Cupola is a view to behold and I’m looking forward to experiencing that."
During their stay, the STS-135 astronauts will be tasked with unloading a giant cargo module of supplies onto the space station and refilling it with trash and other unneeded items for the return to Earth.
Inspecting Atlantis for damage
Yesterday (July 9), Atlantis' four astronauts spent their first full day in space completing a meticulous inspection of their vehicle's heat shield. The crewmates used a sensor-tipped inspection pole to scan the shuttle's heat shield tiles to assess whether anything was damaged during launch and ascent.
The images from the inspection were relayed to ground teams here in Mission Control at Johnson Space Center. Engineers will assess the data and clear the shuttle if there are no issues, or decide to perform additional checks at a later point in the mission's timeline.
Early assessments indicate that there are no significant issues to be concerned about, said Leroy Cain, chair of the shuttle's mission management team.
"The ship has been performing in beautiful fashion," Cain said in a news briefing. "We're not tracking any significant issues. The spacecraft and her crew all seem to be doing very well."