Atlantis' Last Take-Off Scheduled for June 28, 2011

Officials with NASA and the Space Shuttle Program have decided that space shuttle Atlantis will fly the STS-135 mission, its last, on June 28, 2011. This will also be the last launch of the SSP as a whole, crowning nearly three decades of uninterrupted orbiter use.

If all goes according to the current NASA launch manifest, Discovery will fly its STS-133 mission to the International Space Station on February 24, while Endeavor will take off this April.

However, there is currently no way of being sure whether the three planned launches will go on flawlessly. But what's important is that the agency has at least a tentative launch date planned for the STS-135 mission, the “extra” orbiter flight beyond the initially-planned end of the SSP.

US President Barack Obama and Congress approved the extra mission in the 2010 NASA Authorization Act, and called for the agency to make the details of the planned flight available for review as soon as possible.

But there is a catch about Atlantis' last flight, in the sense that it might not take place at all if the shuttle has to be made available as a “Launch on Need” rescue flight for either the STS-133 or STS-134 crews.

Under either of these scenarios, Atlantis would launch from the Kennedy Space Center (KSC), in Florida, in the event that one of its two sister spacecraft and her crew remain stranded in space due to malfunctions, glitches, or other problems.

If such an intervention is not needed, then the space shuttle will carry the multipurpose logistics module (MPLM) Raffaello to low-Earth orbit. The container will include science equipment, spare parts, supplies and personal items for the ISS crew.

The STS-135 mission is designed to be conducted with the minimum number of astronauts possible, four. NASA is unwilling to take any unnecessary risks during this final orbiter flight.

Still, until the mission is approved, there are still legal battles to be fought. The House is bound to vote on some issues related to the 2011 budget. If things go south, NASA could be forced to revert to 2008 funding levels, of just $17.4 billion.

While this could jeopardize Atlantis' launch, analysts say that congressmen from Texas and Florida, the states with most interest in seeing the shuttle fly, will put up a fight, and attempt to secure necessary funding, Universe Today reports.