HIBARI is a space mission byJapan for amicrosatellite that would test a newattitude control (orientation) method to achieve high accuracy pointing for its small telescope, and was launched on 9 November 2021 by anEpsilon launch vehicle as part of theInnovative Satellite Technology Demonstration Program-2 mission.[1] The key technology to be tested onHIBARI is called "Variable Shape Attitude Control" (VSAC), and it is based on reaction torque by rotating its four solar array paddles.
HIBARI is a space mission by the Japanese scientists from theTokyo Institute of Technology to develop high pointing stability and agile maneuvering of a small satellite by using reaction torque of the satellite's structure.[2][3] This technology, first presented in 2016,[4] is hoped to substitute the use ofreaction wheels andcontrol moment gyroscopes (CMG), which arguably have difficulty achieving both agility and stability simultaneously.[2] This capability would be useful for a very fast response to observe in the direction of gravitational waves or other transient astrophysical phenomena.[3]
The spacecraft is a 55 kg (121 lb) microsatellite configured in a 50 cm (20 in) cube,[3] where half of it would carry a smallultraviolet telescope to verify the pointing stability (< 10 𝑎𝑟𝑐𝑠𝑒𝑐2) and accuracy of the VSAC system. The orientation high accuracy would be achieved by rotating the arms of its four solar arrays in an orthogonal axis.[2]Solar cells would be mounted on both sides of each of four solar array paddles.[3]
^イプシロンロケット5号機による革新的衛星技術実証2号機の打上げ結果について [Innovative satellite technology demonstration by Epsilon rocket No. 5 About the launch result of No. 2] (in Japanese). JAXA. 9 November 2021. Retrieved9 November 2021.
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).
