SELENE lunar exploration missions or lunar outpost construction on the Moon between 2018 and 2025. SELENE 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. The orbiter's nickname, Kaguya, was
Orbital station-keeping track it is also necessary to make out-of-plane manoeuvres to compensate for the inclination change caused by Sun/Moon gravitation. These are executed as thruster burns orthogonal to the orbital plane. For Sun-synchronous spacecraft having a constant geometry relative to the Sun, the inclination change due to the solar gravitation is particularly large; a delta-v in the order of 1–2 m/s per year can be needed to keep the inclination constant. For geostationary spacecraft, thruster burns orthogonal to the orbital plane must be executed to compensate for the effect of the lunar/solar gravitation that perturbs the orbit pole with typically 0.85