A few hours after Atlantis docked with the International Space Station, two ships towed the shuttle's twin solid rocket boosters back into port Sunday evening.

After spending the night docked at Port Canaveral, the Freedom Star and Liberty Star recovery boats tugged the boosters up the Banana River to Hangar AF at Cape Canaveral Air Force Station.

Liberty Star towed the right-hand booster and Freedom Star pulled the left-hand booster, identified by a black stripe near its nose.

The boosters arrived at the hangar around mid-morning Monday. NASA says post-flight assessments of the spent motors will begin Tuesday.

Engineers will also remove video cameras from the boosters that recorded views of Atlantis' blastoff Friday afternoon. Imagery analysts will review the footage to search for any debris falling from the shuttle during the two-minute burn of the boosters.

After the motors are jettisoned from the shuttle, the casings tumble back into the lower atmosphere, deploy recovery parachutes, and splash down in the Atlantic Ocean about 140 miles northeast of the Kennedy Space Center.

The boosters that helped launch Atlantis are composed of parts that flew on 57 shuttle flights dating back to the very first shuttle launch in 1981. Booster segments are typically safed, returned to a contractor facility in Utah, refurbished, filled with new solid propellant and shipped back to Florida for another flight.

But with only two more missions remaining, the boosters will not launch another space shuttle. They could be used on future ground tests or demonstration launches of the Ares 1 rocket, if such plans are approved.

Photo credit: Stephen Clark/Spaceflight Now