At 10:28 AM Eastern daylight time yesterday 18 July 2011, a moment that might get lost in spaceflight history occurred on board the International Space Station. (ISS)
After seven days twenty one hour and forty one minutes of docked operations, the main hatch between the ISS and the Space Shuttle Orbiter Atlantis was closed for the final time. It was a seminal moment in the history of both the Space Station and the Space Transportation System program – the way NASA has brought people and cargo into space for the past thirty years.
Never again would the magnificent space craft/aircraft hybrids the Space Shuttle Orbiters, reach for the sky and pay a call on the ISS. The Space Station an almost 100 ton orbiting facility, is a multinational complex that owes its very existence to the Space Shuttle Orbiters.
According to NASA Public Affairs, the total time the Space Shuttle Orbiters Atlantis, Endeavour and Discovery invested in constructing the International Space Station is staggering: Two hundred and thirty four days, fourteen hours and thirty minutes on this project.
With the construction phase now at an end, The ISS has become the orbiting laboratory it was designed to be. The exciting opportunity of using this for microgravity research now begins.
To mark the occasion of this final mission, the crew of the STS 135 mission, Commander Chris Ferguson, Pilot Doug Hurley, and Mission Specialists Sandy Magnus and Rex Walheim, brought with them some mementos. These included a desk model of the Space Shuttle Orbiter signed by John Shannon , the Space Shuttle Program Manager, Leroy Cain, Chair of the Mission Management Team for STS 135, and Lead Flight Director Kwatsi Alibaruho. The little desktop model orbiter is affixed on a bulkhead near the Harmony Node hatch.
Another memento is in the form of a challenge…
In 1981 the maiden voyage of the Space Shuttle Program, Columbia carried on board 1000 small US Flags. These flags were given to those who had made significant contributions to the success of that first flight. One of these flags were carried back into orbit by the crew of STS 135. The small flag is currently attached to the airlock door of the Harmony module, where Atlantis was docked for seven days. The flag is flanked by the mission insignias for STS-1 on its left and for STS-135 on its right.
The final crew of Space Shuttle Atlantis have challenged the various commercial companies hoping to construct and operate a “space taxi” service for cargo and eventually crew to the International Space Station. The challenge is to “Be the first United States spacecraft launched from US soil, with a US crew to successfully dock and board the facility and return the US Flag back home to Earth.”
Right now we can only speculate as to who that company will be but to be sure Elon Musk's company, Space Exploration Technologies or SpaceX is the early favorite.
After who ever brings the flag back home, it will then await another journey into space. It will be carried on the first Orion Multi Purpose Crew Vehicle to break Earth's gravity well. This will be the first US piloted spacecraft to explore deep space since the Apollo missions of the late nineteen sixty’s and early seventies.
After the end of STS 135, the Space Shuttle Orbiters are destined to sit inert in various museum’s throughout the United States, where they will hopefully inspire a new generation of scientists, engineers and astronauts. But their contributions and their impact will be felt for years to come, through the International Space Station and a small US Flag.