rover was canceled by NASA in November 2000 due to budget constraints. In 2002, launch was postponed from December 2002 to May 2003 to recheck the O-rings of its reaction control system since one of them had been found to be using a different material than specified. In 2003, while Hayabusa was en route to Itokawa, the largest solar flare recorded in history damaged the solar cells aboard the spacecraft. This reduction in electrical power reduced the efficiency of the ion engines, thus delaying the arrival at Itokawa from June to September 2005. Since orbital mechanics dictated that the spacecraft still had to leave the asteroid by November 2005, the amount of the time it was able to spend at Itokawa was greatly reduced and the number of landings on the asteroid was reduced from three to two. In 2005, two reaction wheels that govern the attitude movement of Hayabusa failed; the X-axis wheel failed on July 31, and the Y-axis on October 2. After the latter failure, the spacecraft was still able to turn on its X and Y axes with its thrusters. JAXA claimed that since global mapping of Itokawa had been completed, this was not a major problem, but the mission plan was altered. The failed reaction wheels were manufactured by Ithaco Space Systems, Inc, New York, which was later acquired by Goodrich Company. The 4 November 2005, 'rehearsal' landing on Itokawa failed, and was rescheduled. The original decision to sample two different sites on the asteroid was changed when one of the sites, Woomera Desert, was found to be too rocky for a safe landing. The 12 November 2005, release of the MINERVA miniprobe ended in failure. Mission timeline Up to the launch The asteroid exploration mission by the Institute of Space and Astronautical Science (ISAS) originated in 1986–1987 when the scientists investigated the feasibility of a sample return mission to Anteros and concluded that the technology was not yet developed. Between 1987 and 1994, joint ISAS / NASA group studied several missions: an asteroid rendezvous mission later became NEAR, and a comet sample return mission later became Stardust. In 1995, ISAS selected the asteroid sampling as an engineering demonstration mission, MUSES-C, Nereus as the first choice of target, 1989 ML as the secondary choice, and MUSES-C project started in fiscal year 1996. In early development phase, Nereus was considered out of reach and 1989 ML became the primary target. July 2000 failure of M-V forced a delay in the launch from July 2002 to November/December, putting both Nereus and 1989 ML out of reach. As a result, the target asteroid was changed to . In 2002, launch was postponed from December 2002 to May 2003 to recheck O-rings of reaction control system since one of it was found using different material than specification. On May 9, 2003 04:29:25 UTC, MUSES-C was launched by M-V rocket, and the probe was named "Hayabusa". Cruising Ion thruster checkout started on 27 May 2003. Full power operation started on 25 June. Asteroids are named by their discoverer. ISAS asked LINEAR, the discoverer of , to offer the name after Hideo Itokawa, and on 6 August, Minor Planet Circular reported that the target asteroid was named Itokawa. In October 2003, ISAS and two other national aerospace agencies were merged to form JAXA. On 31 March 2004, ion thruster operation was stopped to prepare for the Earth swing-by. Last maneuver operation before swing-by on 12 May. On 19 May, Hayabusa performed Earth swing-by. On 27 May, ion thruster operation was started again. On February 18, 2005, Hayabusa passed aphelion at 1.7