Space shuttle Atlantis' crew began their third day in space at 2:29 a.m. CDT, just hours away from the scheduled final docking of a space shuttle with the International Space Station (ISS).
The wakeup call for commander Chris Ferguson, pilot Doug Hurley, and mission specialists Sandy Magnus and Rex Walheim came in the form of "Mr. Blue Sky" by the British group Electric Light Orchestra. The song was played for Ferguson at the request of his wife and children.
Atlantis has been closing the distance between it and the space station since it reached orbit on Friday, and with the help of a final firing of the shuttle's jets, scheduled for 7:29 a.m., it will finish closing that distance by 9:06 a.m. At that point, the shuttle will be directly below the ISS, and in place for the rendezvous pitch maneuver, a back flip that will expose the thermal protection tiles on Atlantis' underbelly to the station, where crew members will be ready with cameras to document its condition.
Positioned at the windows in the Russian segment of the station, flight engineer Ron Garan will use an 800 mm lens to gather photos of Atlantis' heat shield, while flight engineer Satoshi Furukawa will have a 400 mm lens, and flight engineer Sergei Volkov will use a 1,000 mm.
The back flip will last about eight minutes. Once it's complete, Ferguson will move Atlantis to a point 310 feet directly in front of the space station and begin slowing down so that the station can catch up with the shuttle, for a 10:07 a.m. docking. After a series of leak checks, hatches between the two vehicles are scheduled to open at 12:19 p.m.
Each day that the final space shuttle mission is in flight, collectSPACE plans to highlight milestones and events from the space shuttle's history that also occurred on the same day over the past three decades. "Today in Space Shuttle History" will also note "lasts" being set by the STS-135 mission.
STS-135 Flight Day 3, July 10
1981 Space shuttle Challenger (OV-099), which began life as a structural test article but was converted to be NASA's second shuttle to fly, receives its payload bay doors at its assembly facility in Palmdale, California.
1996 Space shuttle Atlantis, positioned to launch the STS-79 mission from Pad 39A at the Kennedy Space Center in Florida, is rolled back to the Vehicle Assembly Building to take shelter from the threat of severe weather conditions from Hurricane Bertha.
2006 Piers Sellers and Mike Fossum perform the second spacewalk of shuttle Discovery's STS-121 mission. The spacewalkers spent six hours and 47 minutes working outside the International Space Station, restoring its mobile transporter rail car to full operation and installing a spare pump module for the station's cooling system.
2011 Atlantis makes the 37th and final space shuttle docking to the International Space Station.
July 10: Atlantis rolls back in 1996 (left); Discovery astronauts spacewalk in 2006. Credit: NASA
STS-135 commander Chris Ferguson and his three crewmates on board space shuttle Atlantis performed the Terminal Initiation burn at 7:29 a.m. CDT, firing the left orbital maneuvering system engine for 12 seconds.
The engine firing placed them on the final path to a 10:07 a.m. docking at the International Space Station, which at the time, was about eight miles away.
"Poetry in motion as Atlantis conducts the final R-bar pitch maneuver in history."
— NASA mission commentator Rob Navias
With space shuttle Atlantis at a distance of approximately 600 feet below the International Space Station (ISS), commander Chris Ferguson began the rendezvous, or R-bar pitch maneuver at 9:06 a.m. CDT, a slow "back flip" enabling station crew members to photograph the orbiter's thermal protection system through the windows of the station's Russian Zvezda service module.
Using cameras with 400-, 800-, and 1000-mm lenses, Expedition 28 flight engineers Ron Garan, Satoshi Furukawa, and Sergei Volkov recorded imagery of Atlantis' upper and lower outer surfaces. Their photos will be transmitted to Mission Control in Houston, where they'll be analyzed to determine whether the heat shield sustained any damage during launch.
"Atlantis arriving. Welcome to the International Space Station for the last time."
— International Space Station flight engineer Ron Garan
With commander Chris Ferguson in control, shuttle Atlantis docked for its last time — and the space shuttles' final time — with the International Space Station at 10:07 a.m. CDT Sunday as the two vehicles orbited 240 miles up above and east of Christchurch, New Zealand.
The 37th visit by a shuttle to the ISS, Atlantis' arrival begins eight days of joint mission operations between the STS-135 and Expedition 28 crew members. It is expected to take about two hours for the hatches between the spacecraft to be opened.
Station commander Andrey Borisenko together with flight engineers Ron Garan, Alexander Samokutyaev, Sergei Volkov, Satoshi Furukawa, and Michael Fossum will welcome the four shuttle crewmates on board and then brief them on safety procedures before beginning their first activities together.
This was Atlantis' 12th and final docking with International Space Station. It was the 46th shuttle docking to a space station: nine to the Russian Mir station and 37 to the International Space Station.
Atlantis performed seven of the nine Mir dockings.
This was the 86th shuttle rendezvous operation and the 164th "proximity operation" in the history of the space shuttle program, where a shuttle conducted operations in close distance to another spacecraft.
The hatches separating Atlantis and the International Space Station were opened at 11:47 a.m. CST, beginning more than a week of joint crew ops between the four STS-135 astronauts and the six ISS Expedition 28 crew mates.
Following a safety briefing, the 10 members of the combined crew will set to work on their first tasks together. Using the station's robotic arm, flight engineers Ron Garan and Satoshi Furukawa will reach over and unberth Atlantis' 50-foot orbiter boom from the payload bay and then will hand it off to the shuttle's robotic arm under the control of STS-135 commander Chris Ferguson and pilot Doug Hurley.
If needed, the boom will be used later in the mission to perform focused inspections of any potential damage found on Atlantis' heat shield.
NASA's mission managers have been alerted to an old Russian satellite fragment that may cross paths with the International Space Station and space shuttle Atlantis on Tuesday, at the same time that two astronauts are slated to be outside on a spacewalk.
"The team reported that we're following what might be a conjunction, that is to say a piece of orbital debris," said mission management team chair LeRoy Cain in a press briefing held Sunday.
"It looks right now like our point of closest approach would occur on the EVA day, Flight Day 5, during the EVA. However, we don't really have a good PC on it yet — that's the probability of collision — so that all needs to be computed," said Cain.
The debris in question is currently of unknown size, but was identified as a part of Cosmos 375 launched in October 1970.
"We can't say with any certainty if we really have a conjunction but it's a potential," said Cain, who added that he should know for certain Monday.
Of similar minor concern, Atlantis lost use of one of its three navigation computers Sunday, before docking with the International Space Station.
"We did experience a slight problem with one of our General Purpose Computers, or GPCs," said Kwatsi Alibaruho, STS-135 lead shuttle flight director. "Essentially it was really just a transient problem that took down one of those computers for the rendezvous and we had to rendezvous without it. But it represented just a loss of redundancy."
"As we are powering up those computers for the rendezvous and dock, we physically throw a switch in the cockpit that takes the computers that were asleep into an active state. The switches on those computers have detents that can be a little bit temperamental from time to time. If you don't decisively and carefully move the switch from one position to another, there can be a slight rebounding effect that makes the contacts for the switch come off the detent ever so slightly and for the briefest of seconds," he said.
"That happened with our computer No. 3 as the crew was bringing that computer to an active state. The switch came off the detent for just a split second but just long enough for the other two computers that were up to see a change in its state and vote that computer to a failed state."
"We don't think there is anything physically wrong with the computer and in fact, we have to load a new software image to it. We're going to try to do that tomorrow at the beginning of the crew's day," said Alibaruho.
Underscoring that the issue was not of great concern, Alibaruho noted an "interesting" coincidence.
"This exact same problem, the last time it happened was on STS-122, which was also a flight on Atlantis," he said. "There is also one or two other commonalities between this flight and that flight, which I'll let folks research at their leisure."
For one, mission specialist Rex Walheim flew on both flights. But before anyone points fingers, Alibaruho confirmed it was not Walheim who threw the culprit switch today.
Before retiring for the day at 5:59 p.m. CDT, the shuttle and station crew members worked both spacecrafts' robotic arms to pass Atlantis' 50-foot extension boom between them.
STS-135 commander Chris Ferguson and pilot Doug Hurley operated the shuttle's Canadarm to take its orbiter boom sensor system (OBSS) from the station's Canadarm2 operated by station flight engineers Ron Garan and Satoshi Furukawa. The station's arm had plucked the boom from its stowage position on Atlantis' payload bay sill.
The handoff was to prepare to use the boom for any needed shuttle heat shield inspection later this week.
Soon after finishing that work however, Mission Control told Atlantis' crew that the later "focused" inspection may not be needed. Preliminary review of the shuttle's heat shield has cleared it of any potential debris damage requiring a closer look.