Atlantis flies 650 over the International Space Station in this view through the orbiter's docking camera. Photo credit/NASA TV.
The Atlantis astronauts undocked from the International Space Station early Tuesday and backed away to initiate a sweeping arc-like pass over the long axis of the orbiting science laboratory. The departure placed the STS-135 crew in the home stretch of the final flight of NASA's 30-year shuttle program.
The four astronauts soared 650 feet over the station's solar power truss in an unprecedented pass that allowed them to gather close-up imagery of the outstretched solar panels as well as the U. S., European, Japanese and Russian modules clustered in the middle of the 360 foot long orbital outpost.
The two spacecraft separated at 2:28 a.m., EDT, ending a nine day stay for Atlantis commander Chris Ferguson, pilot Doug Hurley, Sandy Magnus and Rex Walheim.
"Thanks so much for hosting us," said Ferguson, just prior to shoving off.
"We can see the International Space Station as a wonderful accomplishment," Ferguson added, as the spacecraft drifted apart. "We will never forget the role of the space shuttle in its creation. We expect great things from you. Farewell. Make us proud."
Station flight engineer flight engineer Ron Garan sounded a ship's bell in nautical tradition at the parting.
Atlantis as viewed from the International Space Station. The Raffaello Multi-Purpose Logistics Module is visible at the rear of the orbiter's payload bay. Photo Credit/NASA TV
"We will miss you guys," said Garan. "See you guys back on Earth."
Hurley backed Atlantis to a distance of 675 feet from the U.S. segment Harmony module shuttle docking port. The veteran pilot held position while Russian thrusters yawed the more than 900,000 pound orbiting science laboratory 90 degrees counter clockwise.
Hurley initiated the 23 minute long axis fly over at 3:28 a.m., easing the orbiter a little closer to the orbital outpost.
A pair of separation maneuvers were to follow.
The imagery gathered by Magnus and Walheim will be examined by NASA station program engineers to document damage from micro-meteoroid and orbital debris impacts as well as atomic oxygen, solar radiation and the other forces of the space environment.
The four astronauts are scheduled to descend to Earth early Thursday, touching down at NASA's Kennedy Space Center at 5:56 a.m., EDT.
The 13-day STS-35 re-supply mission marks the 37th shuttle flight dedicated to station assembly and outfitting since the construction effort began in late 1998 as well as the final journey of the 30-year shuttle program.
Ferguson's crew joined the station's six U.S., Russian and Japanese astronauts on July 10 for a near 9 1/2 ton cargo exchange.
The nearly six tons of food, spare parts, research gear and other supplies that Atlantis delivered are intended to fortify the station for six person operations through 2012 -- long enough for emerging U.S. commercial re-suppliers SpaceX and Orbital Sciences to begin cargo deliveries.
After their separation from the station, the Atlantis crew was scheduled to attach the camera and laser-tipped Orbiter Boom Sensor System to the shuttle's robot arm for a damage survey of the heat shielding that lines the wing leading edges and nose cap of the orbiter.
On Wednesday, the fliers will join with NASA's Mission Control for a check out of orbiter steering and communications systems.