You can helpexpand this article with text translated fromthe corresponding article in Japanese. (December 2018)Click [show] for important translation instructions.
View a machine-translated version of the Japanese article.
Machine translation, likeDeepL orGoogle Translate, is a useful starting point for translations, but translators must revise errors as necessary and confirm that the translation is accurate, rather than simply copy-pasting machine-translated text into the English Wikipedia.
Consideradding a topic to this template: there are already 1,369 articles in themain category, and specifying|topic= will aid in categorization.
Do not translate text that appears unreliable or low-quality. If possible, verify the text with references provided in the foreign-language article.
Youmust providecopyright attribution in theedit summary accompanying your translation by providing aninterlanguage link to the source of your translation. A model attribution edit summary isContent in this edit is translated from the existing Japanese Wikipedia article at [[:ja:かぐや]]; see its history for attribution.
You may also add the template{{Translated|ja|かぐや}} to thetalk page.
Plasma energy Angle and Composition Experiment (PACE)
Radio Science (RS)
Upper-atmosphere and Plasma Imager (UPI)
Relay Satellite aboard Okina (RSAT)
VLBI Radio source aboard Okina and Ouna (VRAD)
High Definition Television cameras (HDTV)
SELENE (/ˈsɛlɪniː/;Selenological and Engineering Explorer), better known in Japan by its nicknameKaguya (かぐや), was the second Japaneselunar orbiterspacecraft following theHiten probe.[5] Produced by theInstitute of Space and Astronautical Science (ISAS) and theNational Space Development Agency (NASDA), the spacecraft was launched on September 14, 2007. After orbiting the Moon for a year and eight months, the main orbiter was instructed to impact on the lunar surface near the craterGill on June 10, 2009.[6]
"The Receding Princess" from The Japanese Fairy Book, 1908
The orbiter's nickname, Kaguya, was selected by the general public. It comes from the name of a lunar princess in the ancientJapanese folktaleThe Tale of the Bamboo Cutter.[7] After their successful release, its sub-satellites,Rstar andVstar, were namedOkina andOuna, also derived from characters in the tale.[8]
The SELENE mission was originally scheduled to launch in 2003, but rocket failures on another mission and technical difficulties delayed the launch until 2007.[11] Launch was planned for August 16, 2007, but was postponed when some electronic components were found to be installed incorrectly.[12]
On October 3, it entered an initial 101-to-11,741-kilometre (63 to 7,296 mi) polar lunar orbit.[13]On October 9, the relay satellite was released into a 100-to-2,400-kilometre (62 to 1,491 mi) orbit, while on October 12 the VLBI satellite was released into a 100-to-800-kilometre (62 to 497 mi) one.[8] Finally, by October 19, the orbiter was in a circular 100-kilometre (62 mi) orbit.[14] 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 50-kilometre (31 mi) orbit, and finally to an elliptical 20-to-100-kilometre (12 to 62 mi) one, with a controlled impact occurring by August 2009.[15] Because of a degradedreaction wheel, the plan was changed so that on February 1, 2009, the orbit was lowered to 50 kilometres (31 mi) ± 20 kilometres (12 mi),[16]and impact with lunar surface occurred at 18:25 UTC on June 10, 2009.[6]
Okina (formerly Rstar) and Ouna (formerly Vstar) were octagonal prisms to support radio science. Okinarelayed radio communications between the orbiter and the Earth when the orbiter was behind the Moon. This allowed, for the first time, the directDoppler shift measurements neededto precisely map the gravitational field of the lunar farside; previously, the farside gravity field could only be inferred by nearside measurements. The relay satellite impacted the lunar farside near theMineur D crater at 19:46 JST (10:46 UTC) on February 12, 2009.[16]
Function: two-way radio science relay, orbiter-earth
Ouna usedVery Long Baseline Interferometry as a second way to map the Moon's gravity field. It was especially useful at thelunar limb, where the gravitational acceleration is perpendicular to the line of sight to Earth, making Doppler measurements unsuitable.
Function: VLBI radio science
Mass: 53 kilograms (117 lb)
Size: 1.0 x 1.0 x 0.65 m (3.3 x 3.3 x 2.1 ft)
Attitude control: spin-stabilized
Power: 70 W
Initial orbit: 100 to 800 kilometres (62 to 497 mi)
First optical still captured by the onboard HDTV camera. Earth is seen at a distance of 11,000 km.[17]
SELENE carried 13 scientific instruments "to obtain scientific data of the lunar origin and evolution and to develop the technology for the future lunar exploration":[18]
Terrain camera (TC) (resolution 10 meters [33 ft] per pixel)[19]
Radio wave source for VLBI (VRAD) aboard Okina and Ouna
Two 2.2 megapixel CCDHDTVcameras, one wide-angle and one telephoto, were also on board, primarily for public outreach.[20] The HDTV system, developed byNHK (Japan Broadcasting Corporation), produced over 1.3 TB of video and stills over 19 months.[21]
JAXA collected names and messages that were carried on SELENE through their "Wish Upon the Moon" campaign.[22] 412,627 names and messages were printed on a sheet measuring 280 mm x 160 mm (11 x 6.3 in) at 70μm (0.0003 in) per character. The sheet was installed under thephotovoltaic modules and cooling panels beneath the multi-layered insulation.[23]
SELENE was part of a renewed global interest in lunar exploration; it was "the largest lunar mission since theApollo program".[28] It followed Japan's first lunar probe,Hagoromo, launched in 1990.[5][29] China launched itsChang'e 1 lunar explorer on October 24, 2007, followed by India's October 22, 2008 launch ofChandrayaan-1 and the United StatesLunar Reconnaissance Orbiter in June 2009. The United States, European countries (ESA), Russia, Japan, India and China are planningfuture crewed lunar exploration missions orlunar outpost construction on the Moon between 2018 and 2025.[30]
^Terada, Kentaro; Yokota, Shoichiro; Saito, Yoshifumi; Kitamura, Naritoshi; Asamura, Kazushi; Nishino, Masaki (2017-01-30). "Biogenic oxygen from Earth transported to the Moon by a wind of magnetospheric ions".Nature Astronomy.1 (2): 0026.Bibcode:2017NatAs...1E..26T.doi:10.1038/s41550-016-0026.S2CID85560607.
Launches are separated by dots ( • ), payloads by commas ( , ), multiple names for the same satellite by slashes ( / ). Crewed flights are underlined. Launch failures are marked with the † sign. Payloads deployed from other spacecraft are (enclosed in parentheses).