 After the successes of the Return to Flight STS-114 and STS-121 missions, and the lessons learned and improvements made following those missions, managers and engineers worked to formulate a plan that would allow the shuttle to service Hubble, while still adhering to the post-"Columbia" safety requirements.On 31 October 2006, Griffin announced that the Hubble servicing mission was reinstated, scheduled for 2008, and announced the crew that would fly the mission, which included Grunsfeld.Senator Mikulski expressed her delight at the news, stating "The Hubble telescope has been the greatest telescope since Galileo invented the first one.