NamesQZS-1 Replacement
Mission typeNavigation
OperatorCabinet Office (Japan) (CAO)
COSPAR ID2021-096A Edit this at Wikidata
SATCAT no.49336Edit this on Wikidata
Mission duration2 years, 4 months and 26 days (in progress)
Spacecraft properties
ManufacturerMitsubishi Electric
Launch mass4,100 kg (9,000 lb) [1]
Dimensions5.4 × 2.9 × 2.9 m (17.7 × 9.5 × 9.5 ft)
Power6.3 kW
Start of mission
Launch date26 October 2021, 02:19:37 UTC
RocketH-IIA 202 (F-44)
Launch siteTanegashima, Yoshinobu LA-Y1
ContractorMitsubishi Heavy Industries
Orbital parameters
Reference systemGeocentric orbit
RegimeMedium Earth orbit
← QZS-4
QZS-5 →

QZS-1R is a Japanese navigation satellite consisting part of the Quasi-Zenith Satellite System (QZSS). QZS-1R will replace the QZS-1 (Michibiki-1) satellite launched in September 2010. QZS-1 has a design life of ten years. As QZS-1 is an experimental satellite, it did not broadcast the MADOCA (Multi-GNSS Advanced Demonstration tool for Orbit and Clock Analysis) signal, which can be used for centimeter-order navigation.[2][3] With the launch of QZS-1R, all satellites of QZSS will be capable of transmitting in the MADOCA signal, reaching operational capacity.[2]


QZS-1R is the fourth operational Quasi-Zenith Satellite to be launched. The design of the satellite is based on QZS-2 and 4, with minor differences such as an increase in the number of temperature sensors on board.[4][5]


QZS-1R was launched on 26 October 2021 by Mitsubishi Heavy Industries.[4]


  1. ^ "みちびき初号機後継機の概要" (in Japanese). Cabinet Office (Japan). Retrieved 26 October 2021.
  2. ^ a b "種子島で内閣府担当者が語る、初号機後継機打上げへの道のり" (in Japanese). Cabinet Office (Japan). 21 October 2021. Retrieved 26 October 2021.
  3. ^ "MADOCA Products". JAXA. 3 August 2020. Retrieved 26 October 2021.
  4. ^ a b Matumura, Takehiro (25 October 2021). "H-IIAロケット44号機の打ち上げは10月26日に1日延期「みちびき」初号機後継機を搭載". 宇宙(そら)へのポータルサイトsorae.jp (in Japanese). Retrieved 26 October 2021.
  5. ^ "打ち上げ間近のみちびき初号機後継機。開発者に聞く" (in Japanese). Cabinet Office (Japan). Retrieved 26 October 2021.