COSPAR ID2005-031B
SATCAT no.28810
Spacecraft properties
Launch mass72 kg (159 lb)
Dimensions72 cm × 62 cm × 62 cm
Start of mission
Launch date24 August 2005 (2005-08-24)
Launch siteBaikonur Pad 109/95[1]
Orbital parameters
Reference systemGeocentric
Semi-major axis6,975.4 km (4,334.3 mi)
Periapsis altitude578.19003
Apoapsis altitude616.33149
Period96.63 min
Mean motion14.9020938 rev/day
EpochMay 3, 2018, 22:37:00.128 UTC[2]
25 μm-thick polyimide mirrors

Reimei ('Dawn') is the in-flight name for a small Japanese satellite known during development as INDEX (INnovative-technology Demonstration Experiment), developed in-house at JAXA both to serve as a demonstration of small-satellite technologies (particularly high-performance and high-accuracy attitude control) and to perform simultaneous optical and charged-particle observation of the aurora. A notable feature is the 25 μm-thick polyimide mirrors used for concentrating sunlight onto the solar arrays.

It is 72 cm × 62 cm × 62 cm and weighs 72 kilograms. The construction budget was $4 million. The satellite was launched into a near-sun-synchronous 630 km orbit on 24 August 2005 as a piggyback on the OICETS launch on the Dnepr launch vehicle.[3][4]


  1. ^ Wade, Mark. "Reimei". Retrieved 7 June 2020.
  2. ^ "INDEX - Orbit". May 3, 2018. Retrieved May 4, 2018.
  3. ^ Saito, Hirobumi (2006), "Overview and initial in-orbit status of "INDEX" satellite", Proceedings of the 20th Annual AIAA/USU Conference on Small Satellites, SSC06-IV-1
  4. ^ "Innovative-technology Demonstration Experiment REIMEI" (PDF). JAXA. Retrieved 2015-12-19.