Funding
With support from both the House of Representatives and the Senate, the fate of STS-135 ultimately depended on whether lawmakers could agree to fund converting the mission from launch-on-need to an actual flight. On 15 July 2010, a Senate committee passed the 2010 NASA reauthorization bill, authored by Senator Bill Nelson, to direct NASA to fly an extra space shuttle mission (STS-135) pending a review of safety concerns. The bill still needed the approval of the full Senate. A draft NASA reauthorization bill considered by the House Science & Technology Committee did not provide for an extra shuttle mission. On 22 July 2010, during a meeting of the House Science Committee, U.S. Rep. Suzanne Kosmas successfully amended the House version of the bill to add an additional shuttle mission to the manifest.
On 5 August 2010, the Senate passed its version of the NASA reauthorization bill, just before lawmakers left for the traditional August recess. On 20 August 2010, NASA managers approved STS-135 mission planning targeting a 28 June 2011 launch. On 29 September 2010, the House of Representatives approved the Senate-passed bill on a 304–118 vote. The bill, approved by the U.S. Congress, went to President Barack Obama for his signature.
On 11 October 2010, Obama signed the legislation into law, allowing NASA to move forward with STS-135, though without specific funding. Generally, the average cost of a shuttle mission was about $450 million.
On 20 January 2011, STS-135's designation was officially changed from STS-335. On 14 February 2011, NASA managers announced that STS-135 would fly regardless of the funding situation in Congress.
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