SELENE (; Selenological and Engineering Explorer), better known in Japan by its nickname , was the second Japanese lunar orbiter spacecraft following the Hiten probe. Produced by the Institute of Space and Astronautical Science (ISAS) and the National Space Development Agency (NASDA), the spacecraft was launched on September 14, 2007. After successfully orbiting the Moon for a year and eight months, the main orbiter was instructed to impact on the lunar surface near the crater Gill on June 10, 2009. Nickname The orbiter's nickname, Kaguya, was selected by the general public. It comes from the name of a lunar princess in the ancient Japanese folktale The Tale of the Bamboo Cutter. After their successful release, its sub-satellites, Rstar and Vstar, were named Okina and Ouna, also derived from characters in the tale. Mission objectives The main scientific objectives of the mission were to: Study the origins of the Moon and its geologic evolution Obtain information about the lunar surface environment Perform radio science, especially precise measurement of the Moon's gravity field Launch SELENE launched on September 14, 2007, at 01:31:01 UTC on an H-IIA (Model H2A2022) carrier rocket from Tanegashima Space Center into a (perigee) / (apogee) geocentric parking orbit. The total launch mass was . The SELENE mission was originally scheduled to launch in 2003, but rocket failures on another mission and technical difficulties delayed the launch until 2007. Launch was planned for August 16, 2007, but was postponed when some electronic components were found to be installed incorrectly. Lunar operations On October 3, it entered an initial polar lunar orbit. On October 9, the relay satellite was released into a orbit, while on October 12 the VLBI satellite was released into a one. Finally, by October 19, the orbiter was in a circular orbit. The nominal mission duration was one year plus possible extensions. On October 31, 2007, Kaguya deployed its Lunar Magnetometer, Lunar Radar Sounder, Earth-looking Upper Atmosphere and Plasma Imager. On December 21, 2007, Kaguya began regular operations after all fifteen observation experiments had been satisfactorily verified. Kaguya completed the planned operation by the end of October 2008 and began extended operations planned to continue through March 2009. It would then be sent into a circular orbit, and finally to an elliptical one, with a controlled impact occurring by August 2009. Because of a degraded reaction wheel, the plan was changed so that on February 1,