| Reimei | |
| Operator: | JAXA |
| Launch Site: | Baikonur Pad 109/95[1] |
| Cospar Id: | 2005-031B |
| Satcat: | 28810 |
| Dimensions: | 72 cm × 62 cm × 62 cm |
| Orbit Reference: | Geocentric |
| Orbit Regime: | Low Earth orbit |
| Orbit Semimajor: | 6975.4km (4,334.3miles) |
| Orbit Eccentricity: | 0.0027340 |
| Orbit Inclination: | 98.1777 |
| Orbit Apoapsis: | 616.33149 |
| Orbit Periapsis: | 578.19003 |
| Orbit Period: | 96.63 min |
| Orbit Mean Motion: | 14.9020938 rev/day |
| Orbit Epoch: | May 3, 2018, 22:37:00.128 UTC[2] |
| Instruments: | 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 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]