Endeavour Leaves the ISS Forever

For the last time ever, the space shuttle Endeavour separated from the International Space Station (ISS) on Sunday, ready to begin its trip back home. Its final mission ever will conclude with a June 1 landing.

The two spacecraft separated at 11:55 pm EDT (0355 GMT on May 30), as the shuttle was getting ready to test out a new, laser-based guidance and docking system. These tests call for it to remain in space, without reattaching to the station again.

The orbiter concluded its mission after 10 days, 23 hours and 45 minutes of remaining docked to the largest orbital structure ever built. All in all, the shuttle is scheduled to spend 16 days in space.

Astronauts from the STS-134 crew and Expedition 28 had a warm goodbye ceremony before the two spacecraft separated from each other yesterday. It was really great seeing you guys,” NASA astronaut and Expedition 28 flight engineer Ron Garan said.

“We were just in awe of the finely oiled machine that was STS-134. On behalf of Expedition 27, Expedition 28, we want to thank you for leaving the space station ready for its continued utilization, for at least the next decade. You really left us in good shape,” he said as the hatches were closing.

During STS-134's stay on the station, astronauts carried out four spacewalks. The purpose of these extravehicular activities (EVA) was to install new components and space parts outside the ISS, to fix leaks in a cooling loop, to secure a new experiment on the outer hull of the facility and more.

It was good “to see the shuttle crew visiting here when we were working, and I'm happy that the crew has completed the task and I'm glad that they enjoyed staying and working with us as well. Thank you very much and soft landing,” said Expedition 28 Commander Andrey Borisenko.

The most important contribution that Endeavour brought was the installation of the Alpha Magnetic Spectrometer (AMS), the most complex and expensive scientific experiment ever flown to space.

The $2 billion particle detector will study high energy cosmic rays, in hopes of gaining a better understanding on the nature of dark matter, dark energy and antimatter. Its studies could help forward our knowledge of the Universe.

“I just want to say, on behalf of the STS-134 crew, that we had a very successful mission working with Expedition 28,” NASA astronaut and STS-134 Commander Mark Kelly said before undocking.

“It's been a great number of days docked. We're looking forward to getting home and we're going to leave these guys to a little peace and quiet,” he added, quoted by Space.

The shuttle will land at the Kennedy Space Center (KSC), in Florida, on June 1, wrapping up its 25-flights-long career as a NASA orbiter. Upon its return, it will be decommissioned, and then sent to the California Science Center, in Los Angeles, for permanent display.